Quick viewing(Text Mode)

3-8 August, 1998 & Flagstaff, Arizona 86011

3-8 August, 1998 & Flagstaff, Arizona 86011

ABSTRACTS OF PAPERS SCHEDULED FOR THE 52ND ANNUAL MEETING OF THE PHYCOLOGICAL SOCIETY OF AMERICA AT NORTHERN ARIZONA UNIVERSITY; FLAGSTAFF, ARIZONA 3-8 AUGUST, 1998

EDITED BY

DAVID F. MILLIE SOUTHERN REGIONAL RESEARCH CENTER, AGRICULTURAL RESEARCH SERVICE, U. S. DEPARTMENT OF AGRICULTURE, NEW ORLEANS, LOUISIANA 70124 USA

PAUL KUGRENS DEPARTMENT OF BIOLOGY, COLORADO STATE UNIVERSITY, FORT COLLINS, COLORADO 80528 USA

&

LAWRENCE FRITZ DEPARTMENT OF BIOLOGY, NORTHERN ARIZONA UNIVERSITY, FLAGSTAFF, ARIZONA 86011 USA 2 ABSTRACTS

PHYCOLOGICAL SOCIETY OF AMERICA

The Phycological Society of America was founded in 1946 to promote research and teaching in all fields of Phycology. The society publishes the research bimonthly in the Journal of Phycology and quarterly in the Phycological Newsletter, as well as the Applied Phycology Forum. Annual meetings are held, often jointly with other national or international societies of mutual member interest. At each annual meeting the society sponsors a Distinguished Lecture by an outstanding scientist. Phycological Society of America awards include the Bold Award for best student paper, the Provasoli Award for outstanding papers published in the Journal of Phycology, and the Prescott Award for the best Phycology book published within the previous two years. The society provides financial aid to graduate student members through Croasdale Fellowships for enrollment in phycology courses at biological stations, Hoshaw Travel Awards for travel to the annual society meeting, and Grants-In-Aid for supporting research. To join the Phycological Society of America, contact the membership director.

President: Richard M. McCourt, Department of Botany, Academy of Natural Sciences, 1900 Benjamin Franklin Parkway, Philadelphia, PA 19103 USA; Telephone: (215) 299-1157, Facsimile: (215) 299- 1028, Electronic Mail: [email protected]

Past President: Lynda J. Goff, Department of Biology, Earth & Marine Sciences Building, University of California-Santa Cruz, Santa Cruz, CA 95064 USA; Telephone: (408) 459-2832, Facsimile: (408) 459-4822, Electronic Mail: [email protected]

Vice President/President Elect: Paul Kugrens, Department of Biology, Colorado State University, Fort Collins, CO 80523 USA; Telephone: (970) 491-7551, Facsimile: (970) 491-0649, Electronic Mail: [email protected]

Secretary: Jane C. Gallagher, Biology Department, City University of New York, 138th St. at Convent Ave., New York NY 10031 USA; Telephone: (212) 650-8507, Facsimile: (212) 650-8585, Electronic Mail: [email protected]

Treasurer: Kyle D. Hoagland, Department of Forestry Fish, & Wildlife, University of Nebraska, 101 Plant Industry, Lincoln NE USA 68583 USA; Telephone: (402) 472-8182, Facsimile: (402) 472-2964, Electronic Mail: [email protected]

Program Director: David F. Millie, Southern Regional Research Center, Agricultural Research Service, U. S. Department of Agriculture, P. O. Box 19687, New Orleans, LA 70179 USA; Telephone: (504) 286-4457, Facsimile: (504) 286-4419, Electronic Mail: [email protected]

Local Organizer: Lawrence Fritz, Department of Biology, Northern Arizona University, Flagstaff, AZ 86011 USA; Telephone: (520) 523-8265, Facsimile: (520) 523-7500, Electronic Mail: [email protected]

Abstracts of papers presented at this year's meeting are published as a supplement to the June issue of the Journal of Phycology and mailed to members. ABSTRACTS 3

1 3Department of Phycology, University of Copenhagen, AN ANTARCTIC FEEDING TRIANGLE: Østerfarimagsgade 2D, Copenhagen K, Denmark CHEMICAL DEFENSE, PHYSICAL DEFENSE, AND MUTUALISM IN MACROALGAE, The 18S rRNA and rbcL genes were determined for URCHINS, AND ANEMONES representative members of the Chrysophyceae. Amsler, C. D.1, McClintock, J. B.1 & Baker, B. J.2 Phylogenetic trees from parsimony and distance analyses 1Department of Biology, University of Alabama at are largely congruent. However, this molecular Birmingham, Birmingham, AL 35294 USA; 2Department phylogeny is starkly at odds with the traditional of Chemistry, Florida Institute of Technology, Pascher/Bourrelly/Starmach scheme of classification for Melbourne, FL 32901 USA the class. For example, Chromulina nebulosa (, Chromulinales) is most closely related We document a unique relationship between red to Chrysamoeba pyrenoidosa (Chrysamoebaceae, macroalgae ( antarctica and Iridaea Chrysamoebales). Also, Cyclonexis annularis cordata), the sea urchin , and the (Ochromonadaceae, Ochromo-nadales) is most closely sea anemone Isotelia antarctica. We have shown that related to Phaeoplaca thallosa (Phaeoplacaceae, both macroalgal are chemically defended against Phaeoplacales). Some genera, such as and herbivory by S. neumayeri. This is supported by Epipyxis, have been considered to be so closely related studies showing macroalgae to be only minor that some workers have placed them in a single ; components of the urchin gut contents. However, molecular data suggest they are distantly related. urchins prefer to cover themselves with these Ultrastructural data, where available, generally support macroalgae. At sites in nature where macroalgal drift is the molecular phylogenies. For example, Hibberdia and present, over 95% of the urchins use macroalgae as Chromophyton have very similar flagellar apparatuses, cover and the vast majority of available drift is being and they are sister taxa in molecular analyses. held by them. When presented with equal amounts of Conversely, Lagynion is reported to have a flagellar macroalgae and other cover materials in the laboratory, apparatus similar to Hibberdia, but these genera are "naive" urchins collected at sites without macroalgae inferred to be distantly related in our analyses of have a strong preference for macroalgae. The major molecular data. The recent removal of several groups predator on sea urchins in this system is the sea from the Chrysophyceae [e.g., Chrysomeridiophyceae, anemone I. antarctica. The presence of algal cover on Dictyocophyceae (including pedinellids and the urchins significantly increases the likelihood of ), Haptophyceae, escape from I. antarctica during a predation event (including Sarcinochrysidales), Phaeothamnio-phyceae, because the anemones' tentacles attach to the algae, and Synurophyceae] and the recent addition of which the urchins then release as they escape. This ultrastructural and molecular data indicate that the defense is physical, not chemical, as thalli from which classification scheme for the Chrysophyceae should be defensive chemicals have been extracted are equally re-evaluated. protective. The macroalgae benefit from this unique relationship because large numbers of fertile drift plants 3 are retained in the photic zone by these dominant, IDENTIFICATION OF GENES EXPRESSED circumpolar urchins and, presumably, continue to SPECIFICALLY WHEN THE CENTRIC release spores and contribute to the gene pool rather THALASSIOSIRA WEISSFLOGII UNDERGOES than being washed onto shore or into deep water. Armbrust, E. V. 2 Marine Molecular Biotechnology Laboratories, School PHYLOGENY OF CHRYSOPHYCEAE USING 18S of Oceanography, University of Washington, Seattle, rDNA AND rbcL SEQUENCES, WITH WA 98195 USA COMMENTS ON ULTRASTRUCTURE AND CLASSIFICATION An intriguing aspect of the diatom life cycle is that each Andersen, R. A.1, Potter, D.2, Daugbjerg, N.3 & mitotic division creates one daughter cell that is the Bailey, J. C.1 same size as the parent cell and one daughter cell that is 1Bigelow Laboratory for Ocean Sciences, West Boothbay slightly smaller. Thus, the mean cell size of most Harbor, ME 04575 USA; 2Department of Pomology, diatom populations decreases over successive University of California, Davis, CA 95616 USA; generations. A common manner of escaping this trend 4 ABSTRACTS of diminishing cell size is through sexual reproduction. is coiled and interlaced within the oil body. Importantly, only those cells with diameters below a Confirmatory freeze-fracture photomicrographs of minimum size can be induced to undergo gametogenesis Schizochytrium sp. exhibited fracture planes with and subsequent (auxospore) formation. The terraces averaging 52.18 + 6.8 Å in height and newly formed auxospore expands to generate a post- correspond to the combined width of two halves of two auxospore cell which is much larger than either parent light bands and one dark band observed in the high cell and is once again resistant to sexual induction cues. pressure freeze substitution photomicrographs. The As a first step towards understanding the molecular results suggest the triacylglycerols within basis for this coupling between cell size and Schizochytrium sp. oil bodies may be organized in a responsiveness to sexual triggers, genes expressed triple chain length structure and a model for this specifically during gametogenesis have been identified. structure is proposed. These results are also compared Two clonal cell lines of the diatom Thalassiosira to oil bodies in electron micrographs of several weissflogii have been isolated; cells from one line have comparable oil-producing species of fungi and algae relatively small cell diameters and can be induced to with known fatty acid compositions employing the same undergo gametogenesis whereas cells from the other line high-pressure freeze substitution technique. have relatively large cell diameters and are immune to the same induction cues. A PCR-based technique has 5 been used to compare the genes expressed by these two COMPARISON OF SPIRULINA GROWTH IN A cell lines upon exposure to an induction trigger. A TUBULAR BIOREACTOR AND AN OPEN subtraction library of partial cDNAs expressed only in RACEWAY POND those small cells undergoing sexual reproduction has Bagherpour, S. & Sperrazzo, P. been created. Eight distinct cDNAs have thus far been Rehnborg Center for Nutrition and Wellness, Nutrilite identified and are now being sequenced. Possible roles Division, Amway Corporation, Lakeview, CA 92567 played by these genes during gametogenesis will be USA discussed. Outdoor mass culture of Spirulina has traditionally been 4 carried out in open raceway ponds and there are ELECTRON MICROSCOPY MAY REVEAL numerous commercial operations that utilize this STRUCTURE OF DOCOSAHEXAENOIC ACID- method. However, many publications have RICH OIL WITHIN THE STRAMENOPILE, demonstrated the advantages provided by enclosed SCHIZOCHYTRIUM SP. culture systems, and work in this area has led to the Ashford, A.1,2 & Barclay, W. R.2 development of several prototypes. We report initial 1Department of Biology, University of Colorado at results using a small scale enclosed tubular reactor Denver, Denver CO 80217 USA; 2OmegaTech, Inc., system recently installed at our facility in Lakeview, Boulder, CO 80301 USA California. This tubular system which utilizes computer control to continuously monitor culture parameters will As a thraustochytrid, Schizochytrium sp. is a unicellular be described, as well as data detailing the growth and algae-like microorganism closely related to the productivity of enclosed and open systems operating algae. Schizochytrium sp. is utilized for the under identical environmental conditions. commercial production of docosahexaenoic acid (DHA)- rich oil and biomass for use as food and feed ingredients 6 such as dietary supplements and DHA for infant GENETIC VARIABILITY AMONG ISOLATES OF formulae. Electron microscopic analysis of TWO SPECIES OF BROWN TIDE ALGAE Schizochytrium sp. employing cell sample preparation Bailey, J. C. & Andersen, R. A. by high pressure freeze substitution revealed possible Bigelow Laboratory for Ocean Sciences, West Boothbay secondary and tertiary semi-crystalline/crystalline Harbor, ME 04575 USA structures of the triacylglycerols within the microbial oil bodies. A fine secondary structure consisting of Episodic blooms of the picoplanktonic "brown tide" alternating light and dark-staining bands was observed algae Aureococcus anophagefferens and Aureoumbo inside the oil bodies. The dark bands were 28.78 + lagunensis (Pelagophyceae) along the coasts of the 1.35 Å in width and light bands were 21.56 + 1.35 Å in northeastern US and in the Laguna Madre basin of width. The tertiary (three-dimensional) structure Texas, respectively, have disrupted marine ecosystems appears to be a multi-layered ribbon-like structure which and negatively impacted fisheries. Although ABSTRACTS 5 physiological and taxonomic studies of these algae have presence of fucoxanthin, diadinoxanthin, diatoxanthin, been published, little is known of their genetic diversity heteroxanthin and ß,ß-carotene. The combination of or population biology. We used molecular biological fucoxanthin and heteroxanthin are not found in any tools to determine the level of genetic variability within other chromophyte algal class. Phylogenetic analysis of geographically and temporally defined isolates of rbcL and 18S rRNA gene sequences will be presented; Aureococcus and Aureoumbo. Complete nucleotide these data position the within a sequences for the nuclear 18S rRNA gene, the plastid- clade that also includes the Phaeophyceae and encoded rbcL gene, as well as the RuBisCO spacer Xanthophyceae. Other genera that are best classified in region have been determined for four isolates of the Phaeothamniophyceae include Chrysoclonium, Aureococcus. Sequences for each of these three regions Phaeobotrys, Phaeogloea, Sphaeridiothrix, of DNA are identical in all Aureococcus isolates. The Tetrachrysis, Tetrasporopsis and, perhaps, Chrysapion, 18S rRNA sequences determined in our laboratory for Koinopodion, Selenophaea, and Tetrapion. Aureococcus do, however, differ from a previously published sequence for this organism. Both rbcL and 8 RuBisCO spacer sequences have also been deduced for CHANGES IN INTRACELLULAR C:N RATIO three isolates of Aureoumbo. Sequences for these DNA DURING GROWTH OF MARINE MICROALGAE regions were found to be identical in each of the three UNDER BATCH CULTURES Aureoumbo isolates and are different from those for Barbarino, E.1, Aidar, E.2 & Lourenco, S.O.1 Aureococcus. In contrast to the sequence data where 1Department of Botany, Institute of Biology, Federal variability has yet to be found within species, genetic University of Rio de Janeiro, Rio de Janeiro, RJ Brazil; polymorphisms among the three Aureoumbo isolates 2Department of Biological Oceanography, have been revealed by RAPD markers and this Oceanographic Institute, University of Sao Paulo, Sao technique is now being applied to Aureococcus isolates Paulo, SP Brazil as well. Results of analyses of new isolates as well as DNA fingerprinting studies will be presented. Under batch cultures the chemical composition of microalgae may vary largely, as a complex response to 7 experimental conditions. The C and N contents of ten THE PHAEOTHAMNIOPHYCEAE: A NEW marine microalgae were studied at mid-log, late-log and CLASS OF CHROMOPHYTE ALGAE stationary growth phases of cultures. Species were Bailey, J. C.1, Bidigare, R. R.2 & Andersen, R. A.1 cultured with Conway medium, with and without 1Bigelow Laboratory for Ocean Sciences, West addition of bubbling air. C and N contents show Boothbary Harbor ME 04575 USA; 2Department of different trends of variation during growth of species, Oceanography, University of Hawaii at Manoa, but both elements attained higher percentages in cultures Honolulu HI 96822 USA with bubbling air. Except for Prorocentrum minimum, great changes in C:N ratio occurred during growth of A new algal class, the Phaeothamniophyceae, is microalgae. For each species values of C:N ratio described on the basis of ultrastructural information, obtained with the two treatments were similar at mid-log photosynthetic pigment data, and analysis of plastid and late-log growth phases, varying from 4.36 rbcL and nuclear 18S rRNA gene sequences. Included (Synechococcus subsalsus) to 7.77 (Tetraselmis in the class are, among others, three genera formerly gracilis), but C:N values were higher at the stationary classified in the Chrysophyceae (Phaeschizochlamys, growth phase of cultures that grew with bubbling air, Phaeothamnion and Stichogloea) and one traditionally ranging from 8.82 (Hillea sp.) to 15.7 assigned to the Xanthophyceae (Pleurochloridella). (Nannochloropsis oculata). Cultures under bubbling air Ultra- structural studies indicate that: 1) cell walls are always showed small amounts of intracellular inorganic present in most, if not all, species, 2) zoospore basal nitrogen (IIN), measured as nitrate, nitrite and bodies form an angle of ca. 145 degrees, 3) a multi- ammonium. On the other hand, during all experimental gyred transitional helix is present, 4) a chloroplast girdle period cultures that grew without bubbling air showed lamella is present, 5) the chloroplast genophore is ring- lower total protein per cell and a greater content of IIN, shaped, and 6) numerous electron opaque vesicles are mainly Skeletonema costatum, Chlorella minutissima present consistently at the cell periphery. The chemical and Isochrysis galbana. For cultures carried out under composition of the photosynthetic storage product and high nitrogen concentrations in culture medium, the lack sexual reproduction are unknown. In addition to of suitable carbon supply generates two important chlorophylls a and c, HPLC analysis revealed the 6 ABSTRACTS effects: the occurrence of large pools of IIN within cells Earthrise Farms, Calipatria, CA 92233 USA and a slower production and accumulation of protein. Large, shallow soda lakes occupy the rift valleys in 9 Ethiopia, Kenya and Tanzania and occur in southern EFFECTS OF PAR AND UV-IRRADIANCE ON Africa. Small but numerous soda lakes stretch northeast PHOTOACLIMATION RESPONSES IN A from Lake Chad and are scattered throughout the eastern TROPICAL RED ALGA. and western rift valleys of eastern Africa. These soda Beach, K. S.1,2, Smith, C. M.2 & Okano, R.2 lakes are recognized as among the world’s most 1University of Tampa, Tampa FL 33606 USA; productive ecosystems. A feature of soda lakes 2University of Hawaii at Manoa, Honolulu HI 96822 throughout Africa is persistent, almost unialgal blooms USA of the cyanobacterium, Spirulina platensis (Arthrospira platensis). These lakes form the basis of our knowledge Analysis of absorbance spectra of the red alga, in the mass cultivation of Spirulina. Moreover, it was Ahnfeltiopsis concinna, revealed the capacity of tissues knowledge of the human use of Spirulina by the from canopy and understory to respond to changes in Kanebou tribes around the Lake Chad area, as far back the intensity of PAR. No differences in as 1940, that stimulated research in the utilization of photoacclimation responses were observed for Spirulina as human food. Spirulina is now produced experiments performed with A. concinna under PAR- commercially in many countries. Current annual only, PAR+UV-A, and PAR+UV-A+UV-B. In situ, production of Spirulina is estimated at 2,000 metric photoacclimation capacity was manifested as differences tons. In this presentation, the productivity of Spirulina in pigmentation for tissues from canopy to understory in outdoor cultures is discussed in relation to theoretical, microsites of this dense turf. This pigment adjustment and observed upper limits of production in these rift to PAR is dynamic and recovery from irradiance stress valley lakes, citing examples from the world’s largest induced by canopy removal was complete within 25 Spirulina farm located in the Imperial Valley of days. In vivo absorbance spectra allowed simultaneous Southern California. The problems faced in outdoor, observation of multiple pigment pools and monitoring large-scale commercial production of Spirulina also will photoacclimation changes over days in this alga. Insight be discussed. into the cascade of photoacclimation events was revealed by concurrent measurement of pigments and 11 photosynthetic performance. Overall, acclimation from BIOMECHANICS AND SURVIVAL OF THE a sun to shade or shade to sun acclimation states proceeded faster for degradative than for synthetic Bell, E. C. processes. Specifically, phycobilin degradation in Department of Biological Sciences, University of Rhode acclimation to sun from shade was faster than phycobilin Island, Kingston, RI 02881 synthesis in tissues in acclimation from shade to sun. Phycoerythrin-specific absorbance changed to a greater Key to the survival of any sessile marine organism is the extent than did shifts of compensation or saturation ability of the organism's mechanical design to meet the irradiance thresholds in acclimation from shade to sun. demands of its flow environment. Members of the While compensation and saturation irradiances changed order Gigartinales are no exception to this rule, and to a greater extent than phycoerythrin specific even thalli that inhabit "low flow" habitats encounter absorbance in acclimation from sun to shade. Lastly, hydrodynamic forces that can challenge their strength of carotenoid and putative mycosporine amino acid attachment. I will review the biomechanical principles absorbances adjusted in response to changes in incident that are relevant to macroalgae in flow, including the irradiance quantity regardless of irradiance quality. generation of hydrodynamic forces and the measurement This suggests a similar signal transduction mechanism of material properties (e.g., strength, strain, and or other metabolic linkages in this photoacclimation stiffness). I will then discuss strategies for increasing mechanism. thallus survival in flow, either by reducing hydrodynamic forces or increasing attachment strength. 10 In particular, I will address the extent to which the flow SPIRULINA (ARTHROSPIRA) PRODUCTION: environment can constrain thallus morphology and size. FROM THE RIFT VALLEY TO THE IMPERIAL While the focus of this presentation will be on the VALLEY Gigartinales, other examples from the macroalgal Belay, A. & Ota, Y. literature will be presented as well. In closing, I will ABSTRACTS 7 suggest areas for future research that would greatly used for comparisons in many . Since contribute to our understanding of the mechanical design proposed phylogenetic relationships in other green algal of this ecologically and economically important group. taxa based on ultrastructure have been supported by subsequent molecular investigations, a molecular 12 phylogenetic examination of S. capricornutum was THE PHYLOGENY OF GREEN ALGAL AND undertaken. During this study, six Group I introns were PLANT ACTINS discovered within this gene. Previous studies have Bhattacharya, D. & An, S. S. shown that numerous algal taxa contain Group I introns, Department of Biological Sciences, University of Iowa, and in some cases multiple introns have been found in a Iowa City, IA 52242 USA single ribosomal gene. Large numbers of group I Green algae and land plants ('') are sister introns are also observed in some fungal taxa. Group I groups which are phylogenetically subdivided into the introns are removed by folding of the intron into a and the Streptophyta. The common conserved secondary structure that is required for ancestor of this lineage is believed to have been a correct excision. These introns are of evolutionary member of the Prasinophyceae. We have sequenced the interest as a possible relict of an ancient RNA world. actin-encoding cDNAs from Mesostigma viride, Three Group I introns of S. capricornutum are located Scherffelia dubia (Prasinophyceae), Coleochaete at conserved algal intron insertion locations while the scutata, Spirogyra sp. (Charophyceae), and from two remaining three introns are found at novel positions. fern species, Anemia phyllitidis and Psilotum triquetrum The SSU rRNA gene and the introns have been to address Viridiplantae evolution. Phylogenetic sequenced, and are reported here. Putative secondary analyses show Mesostigma to be the earliest divergence structures for these introns are presented. Also, their within the streptophytes and provide evidence for a primary nucleotide similarity to other Group IC1 introns unicellular ancestor for this lineage. This is supported found in algae, fungi, viruses, and other sources is by two conserved actin introns (positions 20-3, 152-1) investigated. shared by Mesostigma and the . The ferns contain multiple copy actin genes that form a 14 monophyletic group positioned outside of the plant actin EARLY STAGES OF COMMUNITY gene radiation. We identify three classes of actins in the DEVELOPMENT: BIOFILMS AND THEIR Viridiplantae (Classes I, II, III). N-terminal "signature" INFLUENCE ON SPORE SETTLEMENT OF sequence analyses support these groupings. The Class I ENTEROMORPHA FLEXUOSA actins include the single copy genes of the green algae Borgeas, H. B. & Smith, C. M. and the multiple copy genes of the ferns. The Class II University of Hawaii, 3190 Maile Way, Honolulu, HI plant actins are often expressed in vegetative structures. 96822 USA The Class III plant actins trace their ancestry within the Class II sequences and contain members that are largely The accretion of abiotic and biotic materials on expressed in reproductive structures. substrates submerged in the marine environment results in the development of a complex biofilm. The 13 characterization of early films from coastal areas on MULTIPLE GROUP I INTRONS IN THE SSU O'ahu, Hawai'i was evaluated both spatially and rRNA GENE OF THE CHLOROPHYCEAN temporally via epifluorescence microscopy coupled with ALGAE SELENASTRUM CAPRICORNUTUM fluorescently-labeled lectins. Variation in the richness Booton, G. C., Floyd, G. L., & Fuerst, P. A. and evenness of lectin-specific glycoconjugates over 1, Department of Molecular Genetics, The Ohio State 3, 24, & 72 hr aged films demonstrated significant University, Columbus, OH 43210 USA differences in early biofilms (1, 3, & 24 hr), but not between 24 & 72 hr films. Multi-species biofilms of A phylogenetic investigation of the green alga different ages were observed to influence the process of Selenastrum capricornutum utilizing the small subunit spore settlement in Enteromorpha flexuosa, a common ribosomal RNA gene (SSU rRNA) has revealed fouling green alga. On surfaces immersed for 0, 1, 3, numerous Group I (subset IC1) introns. Selenastrum 24, & 72 hr in Pearl Harbor, a positive correlation was capricornutum is an autosporic, uninucleate alga in the detected between spore settlement of E. flexuosa and order Chlorellales. Ultrastructural examination of S. film age. Bacteria are an important component of capricornutum for phylogenetic studies is limited biofilms and monospecific bacterial films used to because it lacks motile cells and the flagellar structures evaluate settlement in a fouling invertebrate, Hydroides 8 ABSTRACTS elegans, were further tested with E. flexuosa. All 1University of Maine, Orono, ME 04469, USA; monospecific films tested were found to have decreased 2Carleton University, Ottawa, ON K1S 5B6 Canada spore settlement by the time the films were aged for 72 hrs. Films composed of a Bacillus sp. had significantly Fucoid receptacles were studied with cryo-scanning lower settlement in contrast to the Vibrio and electron microscopy and X-ray microanalysis as part of Pseudomonas spp. Spores of E. flexuosa and the larvae studies of the mechanism of release. of H. elegans were found to not respond similarly to Receptacles were cryo-fixed in the intertidal zone (Fucus cues present in two of the three bacterial films tested. vesiculosus, Schoodic Point, Maine) with liquid This research provides an important link in nitrogen-cooled copper pliers or in laboratory cultures understanding how biofilms can influence early stages of (Pelvetia compressa, from California) with liquid development of algal communities. nitrogen-cooled ethane or copper pliers. The specimens were held in liquid nitrogen until planed to a smooth 15 transverse face in a cryo-microtome, then examined at - PRODUCTION OF ASTAXANTHIN-RICH 170 oC. The extracellular matrix was sulfur-rich inside HAEMATOCOCCUS: "FROM PETRI DISH TO the conceptacle and chloride-rich between filaments in SALMON DISH" the medulla. Most cells other than epidermal cells and + Boussiba, S. mature oogonia contained high concentrations of K in Microalgal Biotechnology Laboratory, Blaustein the potentiated state (prior to gamete release). Oogonia Institute for Desert Research, Ben-Gurion University of moving through the extracellular matrix between hair the Negev, Sede-Boker Campus, 84990 Israel cell filaments during gamete release were compressed. From December-March on the Maine shore, fucoid Astaxanthin (3,3'-diketo-4'dihydroxy-beta-carotene) receptacles are subject to frequent freezing at low tide. was first described in aquatic crustaceans as an oxidized Receptacles of F. vesiculosus cryofixed on the shore in form of beta-carotene, which gives the carapace of these January (1998) had extensive ice crystal damage. The animals its pinkish color. This pigment is used in epidermal, cortical, and conceptacle tissues were similar aquaculture as a feed supplement in the production of to those of unfrozen receptacles; however, the salmon and shrimps, and as a colorant of in the medullary filaments and extracellular matrix were poultry industry. The green alga Haematococcus disrupted and displaced. These findings suggest 1) that appears to be one of the most promising natural sources fucoidan is confined primarily to the extracellular matrix for this purpose. Though astaxanthin can be synthesized of the conceptacle, and 2) demonstrate why gamete by other algae, bacteria and a few fungi, the amounts release fails in winter despite the presence of mature accumulated by Haematococcus surpass reported . alternative sources. Astaxanthin accumulation in Haematococcus is accompanied by a remarkable 17 morphological and biochemical "transformation" from CONSISTENCY, ACCURACY AND ACCESSI- green motile cells into inert red cysts and mediated by BILITY: PROMOTING COOPERATION AMONG different environmental stress conditions. We have GOVERN-MENTAL AGENCIES, MUSEUMS AND studied different aspects of this process and as an TAXONOMISTS outcome of this research we have put forward a Brigham, A. R. & Kingston, J. C. successful strategy for large-scale production of U.S. Geological Survey, National Water Quality Haematococcus. The core of this biotechnology is a Laboratory, Arvada, CO 80002 USA two-phase production mode: the first phase involves production under controlled environmental conditions of Collectively, environmental assessments performed a high cell density green biomass, followed by a second by governmental agencies represent sizable investments phase in which this biomass is exposed to extreme for sampling, processing, analyzing and preparing environmental conditions, accelerating the encysment publications as well as a rich source of specimens for process to yield an astaxanthin-rich Haematococcus taxonomic and biogeographic research. The availability mass. of published collecting and processing methodologies has improved consistency in these areas, but application 16 of nationally consistent and accurate for algae CRYO-SCANNING ELECTRON MICROSCOPE in North America has not been achieved. Although STUDIES OF THE FUCOID RECEPTACLE efforts such as the Integrated Taxonomic Information Brawley, S. H.1, Speransky, V. V.1 & McCully, M. E.2 System or the National Science Foundation's ABSTRACTS 9

Partnerships for Enhancing Expertise in Taxonomy be untrue. Although tetrasporangial (bisporangia not (PEET) Program represent substantial progress, the seen) apical plugs are present, this study conclusively freshwater algae remain one of the least well-known of demonstrates that tetrasporangial conceptacles are the aquatic assemblages taxonomically and multiporate with deeply sunken pore plates. The fourth biogeographically from a North American perspective. defining character, presence of spermatangia on both This is of serious concern since the lack of taxonomic floor and roof of male conceptacle, is confirmed in this resolution and consistency currently limits the uses of study. This combination of new characteristics and algae, which are potentially powerful environmental reinterpretation of others suggests that C. thuretii is a indicators. Accessibility is linked to accuracy since reduced member of the subfamily Melobesiodeae. taxonomic revisions and monographs are more likely to be complete if specialists have access to greater 19 geographic ranges of specimens. Accessibility can be A BASELINE STUDY OF PHYTOPLANKTON IN enhanced if governmental agencies routinely deposit THE UPPER LAGUNA MADRE, TEXAS material in museums or other depositories and interact Brooks, R. L. & Lehman, R. L. with the taxonomic community. Such vouchering is Center for Coastal Studies, Texas A&M University at recycling in its purest form, achieving triple-duty from Corpus Christi, Corpus Christi, TX 78412 USA collections and specimens obtained as part of government-sponsored projects. Not only are (1) the The Upper Laguna Madre near Corpus Christi, Texas, original agency's goals met through its publications, but is a hypersaline estuarine ecosystem which had been deposition of specimens and sample remnants provides a afflicted with an extended brown tide algal bloom (2) "snapshot" of the environment that establishes (Aureoumbra lagunensis Stockwell, DeYoe, Hargraves, conditions at a specific time and place and (3) ensures et Johnson, gen. et sp. nov.). The bloom began in accessibility for taxonomists for revisionary and January 1990, and extended through summer 1997. biogeographic research. Water column samples were collected at four sites from November 1994 to October 1995. Brown tide 18 population densities were compared with water quality PHYLOGENETIC IMPLICATIONS OF MULTI- parameters including ammonia, nitrates, PORATE TETRASPORANGIAL CONCEPTA- orthophosphates, pH, salinity, dissolved oxygen, water CLES IN THE PARASITIC CORALLINE RED temperature, and to other plankton populations including ALGA, CHOREONEMA THURETII. , dinoflagellates, and zooplankton. Results Broadwater, S.T., LaPointe, E.A. & Scott, J.L. indicated an inverse relationship between brown tide and Department of Biology, College of William and Mary, diatom population densities. Diatoms were the Williamsburg, VA 23187 USA dominant phytoplankton species and varied at each site. dominated at site 1, Navicula at Sites 2 and Choreonema thuretii (Bornet) Schmitz was placed in the 3 and Nitzchia at Site 4. A total of 51 phytoplankton monotypic subfamily Choreonematoideae based on four species and 16 zooplankton species were recorded. The traits: 1) the absence of either secondary pit connections highest diversity occurred at Site 1, the site with the or cell fusions, 2) conceptacles consisting of only a lowest brown tide population. A checklist of single layer of cells, 3) the unusual pairing of uniporate organisms, location, dominance, and abundance will be tetrasporangial conceptacles with apical plugs, and 4) presented. the presence of spermatangia on both the floor and roof of male conceptacles. Except for members of the newly 20 established subfamily Austrolithoideae, C. thuretii is the PORPHYRA SPECIES IN NEW ZEALAND: 18S only coralline red alga with neither secondary pit rDNA SEQUENCING CONFIRMS DIVERSITY connections nor cell fusions. However, the recent Broom, J. E. 1 & Nelson, W. A. 2 demonstration of a parasitic habit in this alga casts doubt 1Department of Biochemistry, University of Otago, on this feature as diagnostic due to the extremely Dunedin, New Zealand; 2Museum of New Zealand, Te reduced nature of the thallus. A second defining Papa Tongarewa, Wellington, New Zealand. characteristic, a conceptacle consisting of only a single layer of cells, is also suspect due both to the definition New Zealand is an archipelago with an extensive of cell layers and to the reduced nature of C. thuretii. coastline and a large latitudinal range (29° to 54°S). The third characteristic, concurrence of apical plugs and The long geographic isolation of the New Zealand uniporate tetrasporangial conceptacles is shown herein to landmass is reflected in a high level of endemism of 10 ABSTRACTS both land and coastal marine organisms. The New Marine Biology & Coastal Research, University of Zealand coast harbours many species of Porphyra South Carolina, Georgetown, SC 29442 USA (Bangiales, Rhodophyta), both epiphytic (5 species) and epilithic (ca. 12 species). The majority of the epilithic We compared the response to N and P enrichments, and species are as yet undescribed, but systematic studies toxicity toward fish of the toxic dinoflagellate, Pfiesteria aimed at delineating and describing these taxa are in piscicida and a second Pfiesteria-like species (not yet progress. Identification of putative species is based on a formally named) that were isolated (unispecies but not variety of criteria, including morphology and life axenic) from two known fish kill sites in the Neuse history. In the present study we have used sequencing Estuary, NC. Both dinoflagellates were acclimated in of the 18S rDNA locus to confirm that entities separated separate cultures for two months under similar on the grounds of life history and morphology are conditions in which they were (a) grown with fish or (b) genetically distinct. Our results confirm the presence of grown with a as algal prey. Nontoxic a number of species, some of which are presently zoospore production (i.e., in the absence of fish) was unnamed, with very divergent 18S rDNA sequences, then compared for each species in separate trials across suggesting long reproductive isolation. gradients of nitrate, ammonium, inorganic phosphate, and organic phosphate enrichment in short-term batch 21 cultures, with or without an N/P-starved cryptomonad CONTRIBUTION OF ALGAL CARBON TO as available algal prey (sufficient prey added to achieve -1 STREAM FOOD WEBS an initial concentration of 5,000 or 50,000 cells mL ). Bunn, S. E.1, Davies, P. M.2 , & Mosisch, T. D.1 The two species differed significantly in response to 1Centre for Catchment and In-Stream Research, both fish and nutrients/algal prey, in timing and overall Australian School of Environmental Studies, Griffith cell production. Pfiesteria piscicida responded more University, Nathan Qld 4111, Australia; 2Department of slowly and attained significantly lower cell densities Zoology, The University of Western Australia, Nedlands when given algae, especially following a diet of live WA 6907 Australia fish. Highest growth of both dinoflagellates occurred with nitrate stimulation and tracked growth of the Forested streams are generally considered to be cryptomonad prey. Our isolate of P. piscicida was heterotrophic, particularly reliant on riparian inputs of significantly more toxic to fish than the Pfiesteria-like carbon and nutrients. We have been studying the species, with 100-fold higher cell density or much importance of riparian vegetation on forest stream longer periods required for lethality from the Pfiesteria- ecosystems in North Queensland, Southeast Queensland like species. Thus far the data indicate that the second and Southwest Australia using stable isotope techniques. known Pfiesteria-like species isolated from natural Rates of respiration and primary production in the habitat is only weakly toxic to fish, relative to P. streams, measured in situ using perspex metabolism piscicida. chambers, are some of the lowest recorded for forest streams in the world. Despite this, stable isotope 23 analysis of primary sources and consumers suggests that ONTOGENETIC DYNAMIC OF THE ABSO-LUTE benthic algae play an important role in these stream CONFIGURATION OF THE FLAGELLAR ecosystems. In this paper we examine several of the APPARATUS OF MALE GAMETES OF CHARA factors that may influence the relative importance of CONTRARIA VAR. NITELLOIDES (CHARALES, benthic algae to stream food webs in different regions of CHAROPHYTA) Australia. Cáceres, E.J., Vouilloud, A.A. & Leonardi, P.I. Laboratorio de Plantas Avasculares, Departamento de 22 Biología, Bioquímica y Farmacia, Universidad Nacional TWO CO-OCCURRING SPECIES FROM THE del Sur, 8000 Bahía Blanca, Argentina "TOXIC PFIESTERIA COMPLEX: " COMPAR- ATIVE N/P STIMULATION AND ICHTHYO- The ontogenetic dynamic of the absolute configuration TOXICITY of the flagellar apparatus of male gametes of Chara Burkholder, J. M.1, Glasgow Jr., H. B.1& Lewitus, A. contraria var. nitelloides (Charales, Charophyta) was J.2 studied. During the different stages of the male 1Department of Botany, North Carolina State University, gametogenesis the following traits were carefully Raleigh, NC 27695 USA; 2Belle W. Baruch Institute for analyzed: basal bodies angles and lengths, basal bodies intermediate zone, microtubular roots angles and ABSTRACTS 11 lengths, "Vierergruppe", distal and proximal fibers, unique aspects of chromophyte cell function i.e. to proximal sheaths, flagellar length, flagellar transversal probe the molecular circuits responsible for light profiles and flagellar tips, etc. Conventional regulation of gene expression and to unravel the transmission electron microscope and serial sectioning biochemical pathways that affect metabolic change. techniques were used. Three principal stages have been found: i) parallel basal bodies connected by a proximal 25 non-striated fiber, ii) basal bodies connected by a distal AN ANALYSIS AND INTERPRETATION OF striated fiber and iii) basal bodies without connection WATER CHEMISTRY, SUBSTRATE, AND fibers. The fact that during the very inception of the DIATOM COMMUNITIES IN MOUNTAIN LAKE, development of the basal apparatus the basal bodies are VIRGINIA parallel to each other and perpendicular to the nuclear Cawley, J. C. & Parker, B. C. envelope is discussed from an evolutionary point of Department of Biology, Virginia Tech, Blacksburg VA view. 24061 USA Mountain Lake is the only natural lake in the 24 unglaciated southern Appalachian Highlands. It is an HETEROSIGMA CARTERAE: A MODEL SYSTEM oligotrophic to meso-oligotrophic freshwater system FOR HARMFUL ALGAL BLOOM STUDIES traditionally exhibiting an oligotrophic algal flora, Cattolico, R. A., Han, M-S., Connell, L., Welling, K., including sparse diatoms of relatively low diversity in Hatheway, W. & Waaland, J. R. plankton collections, and Nitella megacarpa and Elodea Department of Botany, University of Washington, as as native macrophytes. In recent years, the lake has Seattle, WA 98195 USA exhibited early signs of eutrophication, as well as the increasing presence of the non-native macrophyte Three areas of research have been targeted using the Cerataphyllum demersum. Our present study of lake , Heterosigma carterae, as a model water chemistry and nutrients shows the system to be system: 1) Genetic fingerprinting: Sequence analysis largely controlled by phosphorus, and to a lesser extent demonstrates that bio-geographically disparate by nitrate concentrations, from specific individual input populations of the alga encompass a single species. streams and rainwater. Diatoms from modern sediment Taxon-specific DNA hybridization probes have been show different and more diverse forms than those from developed to distinguish this pleiomorphic cell from either plankton or diatometer collections from the lake. other biflagellate, toxic algae (e.g. Fibrocapsal Several previously unreported forms are noted. The japonica, japonica, Olisthodiscus luteus and sediment diatoms comprise several individual thanato- sp.; 2) Life history profiles: communities related to water depth, substrate, and Environmental triggers impact both cell survival and nutrient conditions associated with individual stream toxin biogenesis. Vegetative cells have been induced to sources. In addition, native macrophytes show more form non-motile 8-10 mm "cysts" with 60-70% diverse epiphytic community associations than does efficiency by manipulating light, temperature and Ceratophyllum, which is associated here with a low nutrient loads. "Cysts" kept in the dark for 19-35 days diversity, near monoculture of Cocconeis placentula. can excyst when exposed to favorable environmental These results are being applied to lake sediment core conditions. Unlike these putative "cysts", a large, long- analysis to determine past depth, environmental and lived 18mm "spore" phase, is induced solely by nutrient conditions within the lake. alterations in irradiance. Although the toxicity of these resting phases is presently unstudied, vegetative cells 26 produce a family of allelopathic compounds that kill STRAIN IMPROVEMENT OF SEAWEEDS FOR eco-cohorts at every trophic level. Heterosigma is AQUACULTURE THRU BIOTECHNOLOGY: capable of sequestering a hemolytic toxin of unknown CURRENT STATUS AND FUTURE PROSPECTS molecular identity. 3) Cell function: Heterosigma is an Cheney, D. P.1, Levine, I.2, Rudolph, B.3 & Kapraun, obligate photoautotroph. The relationship between light D.4 availability and the capacity of this alga to enter into an 1Marine Science Center, Northeastern University, active reproductive phase or to transform into a "cyst" Nahant, MA 01908 USA; 2Coastal Plantations or into a "spore" is well established. We hypothesize International, Portland, ME 04101 USA; 3Copenhagen that light may serve as a cue which drives Heterosigma Pectin, DK-4623 Lille Skensved, Denmark; 4Univiversity cell function. Using Heterosigma as a model of North Carolina at Wilmington, Wilmington, NC experimental system, we have begun to document 28403 USA 12 ABSTRACTS

Ceramiales. Preliminary data, based on an SSU The seaweed industry of developed countries like the alignment for 36 ceramialean algae including 12 United States has always been based upon the harvesting ceramiacean, 12 dasyacean, 6 delesseriacean, and 6 of wild native species or cultivated foreign species. rhodomelacean species, remain consistent with the This needs to change if the industry is ever going to notion that the Dasyaceae, Delesseriaceae and expand in the US and other developed countries. One Rhodomelaceae have evolved from a common ancestor way this can be done is by developing aquaculture within the Ceramiaceae. However, our data indicate systems of genetically modified/improved seaweed that the Rhodomelaceae alone is monophyletic with the strains that produce novel, higher-valued products that Dasyaceae polyphyletic and the Delesseriaceae can not be obtained from native or foreign wild plants. paraphyletic. The implications for taxonomy in the Until recently there was little hope that this can be done. Ceramiales will be discussed. However, as a result of recent advancements in protoplast fusion and analogous techniques, we have 28 developed practical methods for the genetic modification INVESTIGATIONS OF PHYCOCOLLOID and improvement of virtually any commercially-valuable BIOCHEMISTRY AS A CHEMOTAXONOMIC red macroalga. To date, we have produced new strains INDICATOR OF PHYLOGENY IN THE of the two major carrageenophytes under cultivation, GIGARTINALES Eucheuma denticulatum and Kappaphycus alvarezii, Chopin, T.1, Kerin, B.1, Morais, T.1, & Saunders, G.2 which demonstrate significantly faster growth rates (up 1Centre for Coastal Studies and Aquaculture, University to 14% per day) in extensive field trials. We have also of New Brunswick, Saint John, NB E2L 4L5 Canada; produced a hybrid/polyploid between the Japanese 2Department of Biology, University of New Brunswick, cultured species Porphyra yezoensis (nori) and a North Fredericton, NB E3B 5A3 Canada Atlantic species, P. umbilicalis , which exhibits an increase in chromosome number and faster growth rate. The taxonomic significance of the polysaccharide Future plans are to produce transgenic nori that can structures of the algal cell walls has been underlined serve as an "edible vaccine" when eaten. several times over the past few decades but never pursued in a systematic manner because, as McCandless 27 put it in 1978 "... division on the basis of constituent PHYLOGENETIC RELATIONSHIPS AMONG polysaccharides is either a taxonomist's nightmare, if SELECTED CERAMIALES (RHODOPHYTA) one looks at the changes in classification which would BASED ON NUCLEAR SMALL-SUBUNIT rDNA have to result, or a biochemist's nightmare, if one looks SEQUENCES: FOCUS ON THE DASYACEAE, at the existing classification and considers the analyses DELESSERIACEAE AND RHODOMELACEAE still to be done"! Many changes in red algal Choi, H-G.1, Kraft, G. T.2, Lee, I. K.3 & Saunders, G. systematics and the biochemical analyses of W.1 phycocolloids have developed since her statement. We 1Department of Biology, University of New Brunswick, are testing whether the method developed by Chopin Fredericton, New Brunswick, E3B 6E1 Canada; 2School and Whalen for carrageenan identification by FT-IR of Botany, University of Melbourne, Parkville, Victoria diffuse reflectance spectroscopy can be extended to the 3052 Australia; 3Department of Biology, Seoul National study of phycocolloids for diverse species of many red University, Seoul 151-742 Korea algal orders. Its rapid screening capability (directly on dried, ground algae) and minimal requirement of Previous molecular investigations of nuclear small- material (only a few milligrams) should reduce the subunit (SSU) rDNA sequences have indicated that the "nightmarish" aspect of this long-term investigation. Ceramiaceae is paraphyletic in excluding a monophyletic Results of FT-IR diffuse reflectance spectroscopy will clade including the Dasyaceae, Delesseriaceae and be considered in light of recent molecular phylogenies to Rhodomelaceae. Furthermore, it is generally accepted determine if key phycocolloid attributes can be identified that these latter three families are themselves that correspond with familial and ordinal level monophyletic. However, only one species for each of groupings. Biochemical alternation of generations is the Dasyaceae, Delesseriaceae and Rhodomelaceae have well documented in species of the Gigartinaceae and been included in previous SSU molecular investigations. , with either isomorphic or The aim of the current investigation is to test the general heteromorphic life histories, studied to date. A acceptance that these three families are monophyletic by secondary aim of this study is to determine if this generating a more robust SSU phylogeny for the pattern holds as more species of these two families are ABSTRACTS 13 investigated, and to ascertain if a similar situation occurs The limits of the value of sequence data for for species of other families and orders. reconstruction of phylogenetic history are still being explored. The utility of nuclear rDNA internal 29 transcribed spacer region sequences (ITS-1 and ITS-2) NOVEL INSIGHTS INTO THE PHYLOGENETIC has been limited by uncertainties of alignment. With the AFFINITIES OF OVALIS & discovery of the secondary structure of the transcripts of KATABLEPHARIS PHOENOKISTRON these regions, more valid alignment is possible. To (KATABLEPHARIDACEAE) SKUJA. examine the taxonomic lower limits of this information, Clay, B. & Kugrens, P. we have sequenced 18 isolates of Gonium pectorale, a Department of Biology, Colorado State University, Fort morphologically uniform species of worldwide Collins, CO 80523, USA distribution. After alignment guided by secondary structure, we assessed their relationships by parsimony The colorless flagellate Katablepharis Skuja is and by nearest neighbor methods. Both give the same comprised of six species based on light microscopic phylogram. We also assessed their mating relationships, studies. Two of the species, K. ovalis and K. both for zygote production and for germination and phoenokistron, are compared at the light microscopic survival of products from . All isolates fall, by and ultrastructural level. For K. phoenokistron, this mating behavior, into one of two complementary mating represents the first ultrastructural study. Although the types that appear to characterize the species. No two species share most cellular characteristics, including member of the species has been found to mate with any a feeding apparatus, alveolar-like sacs associated with other Gonium species, even the most closely related by subpellicular , ejectisomes, and cell cover, sequence, G. octonarium. Within G. pectorale, there they differ in some respects. First, observing the are two major clades by sequence analysis. Mating and cytopharyngeal rings within the feeding apparatus zygote formation can occur between representatives of reveals that K. ovalis possesses two whereas K. these two clades, but no zygote products result. The phoenokistron possesses nine to ten rings. Secondly, K. mating data and the degree of F1 survival parallel ovalis ejectisomes are comprised of a single coil that precisely the relationships suggested by the sequence when forcibly discharged produces a single coiled tube data phylogram. Thus, ITS sequence data seem suitable structure. In contrast, K. phoenokistron appears to for subspecies analyses as well as species and generic harbor, in addition to the type found in K. ovalis, studies. ejectisomes with a large coil attached to a small coil or subsidiary scroll. These bipartite ejectisomes, when 31 discharged, form a long tube with a small attached tube 18S PHYLOGENY OF deflecting out at a circa 45ƒ angle. The question of Deane, J., Strachan, I., Hill, D., Saunders, G. & primitive or advanced regarding the two species is McFadden, G. addressed by comparing them to other protist groups School of Botany, University of Melbourne, Melbourne, that also share these structural features. In addition to Victoria, 3052 Australia intrageneric comparisons, larger scale phylogenetic relationships for Katablepharis are explored. Based on Cryptomonads are a distinct group of unicellular algae ultrastructural studies, an argument is presented for a that have traditionally been classified according to their Katablepharis/cryptomonad relationship. Also, a morphology and colour. They are something of a Katablepharis/apicomplexan relationship is suggested, curiosity because they have obtained their plastid by based on the feeding apparatus and the alveolar-like engulfing and permanently maintaining a photosynthetic structures. The proposals are based upon evidences (the endosymbiont). We have sequenced 12 utilizing comparative ultrastructure, monoclonal nuclear 18S ribosomal RNA genes from species that antibody studies, and phylogenetic studies utilizing the represent a broad range of cryptomonad morphological 18S ssrRNA gene sequence for Katablepharis ovalis. and pigment diversity. By analyzing these new 18S rRNA sequences with 11 cryptomonad sequences 30 completed by previous investigators, we have been able IS DNA SEQUENCE INFORMATION USEFUL AT to identify a number of well supported assemblages THE SUBSPECIES LEVEL? within cryptomonads. Blue/green cryptomonads that Coleman, A. W. contain phycocyanin pigment form a clade distinct from BioMed, Brown University, Providence, RI 02912 USA other species that contain phycoerythrin pigment. Species with a nucleomorph (the endosymbiont nucleus) 14 ABSTRACTS embedded in the pyrenoid form a well supported clade. growth. As such, the lack of coupling between MIB Species containing type II phycoerythrin group with the and algal growth and/or photopigment alteration colourless cryptomonad suggesting that suggests that MIB production may not be a direct means Chilomonas evolved by pigment loss from a species that to dissipate “excess” carbon as has been previously contained type II phycoerythrin. There are a number of postulated. species that do not group together strongly but are similar in that they have a single endosymbiont with a 33 free nucleomorph. This configuration appears to be an ION REGULATION OF MEMBRANE ancestral state that still persists in some cryptomonad TRAFFICKING AND MUCILAGE SECRETION IN lineages. We have also obtained 18S rRNA sequence THE DESMID, CLOSTERIUM for a second species of the plastid lacking heterotroph, Domozych, D. S. & Domozych, C. E. , and our analyses confirm that Department of Biology, Skidmore College, Saratoga Goniomonas spp are related to the cryptomonad host Springs, NY 12866 USA cell, but diverged before an endosymbiont with a plastid was acquired. The desmid, Closterium sp., possesses a complex mucilage-secretory pathway that includes an elaborate 32 endomembrane system (ES) and an active, cytoplasmic RE-EVALUATING THE “OVERFLOW” streaming network (CSN). Central to the ES is a HYPOTHESIS: WHAT IS THE LINK BETWEEN network of over 100 Golgi bodies, each consisting of a PHOTOPIGMENT & 2-METHYLISOBORNEOL well-defined stack of 12-15 cisternae and various SYNTHESIS IN CYANOBACTERIA? secretory vesicles. An extensive but incompletely Dionigi, C. P., Millie, D. F. & Zimba, P. V. described network of F-actin cables is a key component U.S.D.A., Agricultural Research Service, New Orleans, of the CSN. In this study, an experimental and LA 70124 USA immunocytochemical examination of the ES and CSN was undertaken. Treatment with 0.01mM of the sodium Many cyanobacteria produce the terpenoid metabolite 2- ionophores, monensin and SQL, resulted in Golgi methylisoborneol (1-R-exo-1,2,7,7-tetramethyl-bicyclo- alteration that included typical cisternal curling and trans [2,2,1]-heptan-2-ol; MIB) that exhibits a characteristic face swelling. Immunogold labeling using an anti- ‘muddy’ taste and odor. Although non-toxic, MIB is mucilage antibody showed that mucilage processing considered a significant problem in the aquaculture through the Golgi Apparatus was unaffected for the first industry and municipal water supplies because fish hour of treatment. Monensin and SQL also caused and/or potable water containing MIB are undesirable localized formation of wall inclusions in the polar zones. and often misconstrued as unsafe. Previous research These structures are presumably caused by alterations of has indicated that the cell content of MIB accumulates in wall-vesicle fusion sites at specific zones of the response to inhibition of the isoprenoid biochemical plasmamembrane. Likewise, actin cables coalesced pathway; thereby suggesting that MIB biosynthesis together to form brush-like aggregates and cytoplasmic provides a unique mechanism to dissipate excess carbon streaming subsequently ceased. Treatment with calcium in the terpenoid/pigment pathway via an ‘overflow’ channel blockers like verapmil, resulted in CSN mechanism. In a series of culture experiments, cessation and cisternal fusion of the trans face locus of chemically-induced inhibition of the terpene pathway the Golgi Apparatus. Treatment with calmodulin ‘below’ and ‘above’ the branch points of terpenoid and antagonists such as W7, TMB-8 and TFP caused a photopigment synthesis, respectively, in conjunction distinct formation and clustering of coated vesicles at the with varying amounts of photosynthetic active radiation trans Golgi region. Mucilage secretory vesicles were resulted in dramatic alterations of photopigment produced for the first 15 min. of treatment. For longer content/composition within Oscillatoria chalybea and periods of treatment, secretory vesicle production was Pseudanabaena articulata. However, cellular and total halted. A model to explain the multiple roles of specific accumulations of MIB were not altered by these ions in the secretory network will be presented. physiological/environmental perturbations, even when these pertubations were imposed at nearly lethal 34 concentrations/levels. In addition, cyanobacterial GENETIC INVESTIGATIONS OF TWO cultures maintained in the laboratory often are observed DIVERGENT MORPHOLOGIES OF CHONDRUS to reduce or cease MIB biosynthesis; thereby indicating CRISPUS (RHODOPHYTA) USING AMPLIFIED that MIB production is not a requirement for active FRAGMENT LENGTH POLYMORPHISM (AFLP) ABSTRACTS 15

Donaldson, S. L.1, Chopin, T.2 & Saunders, G. W.1 our recently initiated work focusing on the Florida red 1University of New Brunswick, Department of Biology, tide dinoflagellate, Gymnodinium breve, and its Fredericton, NB E3B 6E1 Canada; 2Centre for Coastal associated bacteria, will be presented. Studies and Aquaculture, Saint John, NB E2L 4L5 Canada 36 ROLE OF FIRE ASH ON NUTRIENTS AND Two morphologies of Chondrus crispus Stackhouse FOODWEB DYNAMICS IN A SOUTHWESTERN (Rhodophyta) have been described in the Maritime USA FOREST STREAM provinces of Canada: N (narrow) and B (broad). Earl, S. R. & Blinn, D. W. Hybridization attempts were unsuccesful, possibly Department of Biological Sciences, Northern Arizona indicative of genetic distinctiveness of these two forms, University, Flagstaff, AZ 86011 USA however, environmental forces have also been implicated as causing the morphological divergent of the We tested the short and long term responses of fire-ash N and B varieties. No genetic analyses to date have on a first order stream in the Gila National Forest in been conclusive at resolving population-level genetic New Mexico, USA. Three hundred gallons of fire-ash differences between these two phenotypically divergent slurry, from a nearby wild fire, was delivered to stands of C. crispus. Amplified Fragment Length Meadow Creek over a 75-minute period. Selected Polymorphism (AFLP) is assessed as a method for physico-chemical and biotic responses were monitored resolving genetic structure between the N and B at upstream (control) and downstream (ash treatment) morphologies of C. crispus found in the Maritime sites prior to, during, and at 3 h, 22 h, 1 mo, 2 mo, and provinces of Canada. 9 mo intervals after the ashing event. All major ions and nutrients showed a significant (p < 0.01) increase 35 in concentration during the ashing event with recovery BACTERIAL INFLUENCES ON HAB to control levels within 3 h of the event, except for K, POPULATION DYNAMICS NH3, and NO3, where recovery took up to 22 h after Doucette, G. J., McGovern, E. R. & Babinchak, J. A. treatment. Elevated concentrations of PO4 continued to NOAA/NOS Charleston Laboratory, Charleston, SC be detected at 2 mo following the event. Hydrogen-ion 29412 USA concentration increased from 7.7 to 8.9 during the ashing event, but recovered within 22 h after treatment. It is well-documented that the characteristics of a Dissolved oxygen concentration decreased from 6.3 mg bacterial assemblage change in both a quantitative and L-1 to 5.0 mg L-1, also recovering to control levels within qualitative sense over the course of an algal bloom. It 22 h after treatment. There was no significant has also been suggested that the microbial community difference between control and treatments for periphyton may play either a beneficial or detrimental role in biomass, and only minor compositional changes in the regulating algal growth, often in a species-specific phytobenthic community. Mixed responses were seen manner. However, as a potentially important factor in the invertebrate community, where mayfly nymphs, regulating the population dynamics of harmful algal Hemiptera, and select members of caddis flies appeared blooms (HABs), bacteria have received relatively little to be sensitive to the ashing event. The importance of attention. Recent emphasis on HAB growth regulation, forest fires in the maintenance of stream structure and both from a modeling/prediction perspective, as well as function will be discussed. the development of strategies for bloom mitigation and control, has provided a new impetus for studies of 37 bacterial-algal interactions and their influence on HAB RECOVERY FOLLOWING LONG-TERM dynamics. Our current research is directed at the KELP CANOPY EXCLUSION isolation and characterization of bacteria either lethal to Edwards, M. S. (i.e., algicidal), or adversely affecting the growth of Department of Biology, University of California at HAB species, with emphasis on the mechanism of Santa Cruz, Santa Cruz, CA 95064 USA algicidal activity and the basis of taxonomic specificity for the target algal species. In addition, we are Experiments in Carmel Bay, CA indicated that kelp attempting to discern to what extent interactions between canopy exclusion led to increased cover of perennial turf a given HAB species and its associated bacterial algae and decreased availability of bare space. To assemblage may shape the composition of the latter. An examine if these changes affected kelp recovery overview of work in this area, as well as results from following the study, recruitment of the 16 ABSTRACTS

Macrocystis pyrifera and Pterygophora californica was observations indicate that an organic matrix or template monitored in the exclusion areas (old) and in newly may be directly involved with biomineralization, and established canopy clearings. Recruitment of M. that this material remains associated with the pyrifera did not differ between the clearing types while microarchitecture (i.e., as a scaffolding) following cell P. californica recruitment was greater in newly wall development. established clearings. Removal of turf algae from experimental plots within the clearings led to similar patterns of recruitment between canopy treatments. 39 Survivorship of kelps that recruited epiphytically onto MICROALGAL XANTHOPYHYLL-CYCLE turf algae was lower than of those that recruited onto PIGMENT POOLS AND FUNCTIONALITY AS A bare space. Macrocystis pyrifera recruitment was FUNCTION OF THE SPECTRAL DISTRIBUTION evenly dispersed throughout all of the clearings, while OF STATIC GROWTH LIGHT P. californica recruitment was evenly dispersed in the Evens, T. J. & Chapman, D. J. new clearings, but concentrated near the edges of the Department of Ecology, Evolution and Marine Biology old clearings. Further implications of kelp canopy & The Marine Science Institute, University of California exclusion will be discussed. at Santa Barbara, Santa Barbara CA 93106 USA

38 The effects of high and low, white-light upon EVIDENCE FOR A MICROARCHITECTURE xanthophyll-cycle pigments has been well studied. AND ASSOCIATED ORGANIC MATRIX IN THE However, aquatic light fields present highly unique DIATOM FRUSTULE spectral distributions/photon flux densities that can Egerton-Warburton, L. M.1, Griffin, B. J.3, change on relatively short time scales. We have begun a Ghisalberti, E. L.4, Mulvaney, P.2, & Wetherbee, R.1 series of experiments that will address the effects of 1School of Botany, 2School of Chemistry, The University static and dynamic growth-light upon xanthophyll-cycle of Melbourne, Parkville 3052, Australia; 3Centre for functionality in microalgae. To address the question of Microscopy, 4Department of Chemistry, University of W. static growth-light we observed the effects of three Australia, Nedlands 6907 Australia spectrally distinct growth light regimes upon the pool- size and functionality of the xanthophyll-cycle pigments Diatoms are encased in an intricate and highly ordered of the Chrysophyte, Ochromonas danica. A diffuse frustule that is constructed by precise temporal and white and two diffuse, colored (blue-green and red) spatial patterns of silica deposition. We are filters were used in conjunction with neutral density investigating the biological processes involved in the screening to provide at least three photon flux densities formation of the frustule, as these three-dimensional under each of the three spectral distributions. Pigment composites make ideal systems for modelling the design epoxidation/de-epoxidation kinetics (HPLC), PSII and synthesis of novel materials for advanced fluorescence (PAM), oxygen evolution and in vivo technology. To date, conventional scanning and absorbance characteristics were monitored during both transmission electron microscopy (including electron an increasing and decreasing photon flux density in a diffraction) data suggest that the frustule is relatively modified photosynthesis/irradiance (P/E) cuvette. unstructured, composed of amorphous silica and at best Maximum xanthophyll-cycle induction/relaxation differentiated as ribs or a honeycomb system. Here, we kinetics also were determined. Intercomparison of present field emission scanning electron microscopy growth light regimes was based upon photosynthetically (FESEM) and atomic force microscopy (AFM) data that absorbed radiation (PHAR), as opposed to illustrates the presence of a highly organized photosynthetically available radiation (PAR). microarchitecture within the frustule that has not been described previously. A finely-patterned 40 microarchitecture was observed primarily within the DIVERSITY OF DINOFLAGELLATES AT valve and to a lesser degree within the girdle bands; PELICAN CAYS, BELIZE these structures remain embedded within the heavily Faust, M. A. silicified regions of the frustule. In addition, AFM National Museum of Natural History, Smithsonian imaging coupled with 13C-nuclear magnetic resonance Institution, Suitland, MD 20746 USA (NMR) analyses of acid-washed frustules indicate the presence of an organic matrix material embedded within This study examined the diversity of toxic and non-toxic heavily silicified structures. Together, these marine dinoflagellates in six relatively pristine, ABSTRACTS 17 biologically diverse, semienclosed, oceanic mangrove islands situated within the Pelican Cays Archipelago, The light-limited size-dependence of photo-synthesis, Belize. The atoll-like Pelican Cays exhibit enclosed, respiration, exudation, growth, quantum yield, and light different sized lagoons, associations of mangrove corals absorption was quantified for eight species of centric and seagrass beds, and relatively stable oligotrophic marine diatoms: Chaetoceros calcitrans (Paulsen), conditions. These islands are circular depressions, that Thalassiosira pseudonana, Chaetoceros sp., are separated from the outside ocean by steep coral Thalassiosira weissflogii ((Grunow) Fryxell et Hasle), ridges, that restrict the exchange of water. Hyalodiscus sp., Planktoniella sp., Coscinodiscus sp. Dinoflagellate assemblages were examined in 46 (Ehr. (1839)), and Coscinodiscus sp. The size scaling plankton net tow samples collected at Cat Cay, Douglas exponent associated with the photosynthetic rate is Cay, Elbow Cay, Fisherman Cay, Lagoon Cay, and significantly smaller than the commonly reported Manatte Cay in May, 1994. The associations of exponent of -1/4. In contrast, carbon-specific dinoflagellates are documented in SEM pictures. I have respiratory loss and the specific growth rate have size- identified 58 taxa: Amphidinium (3), Ceratium (8), scaling exponents close to -1/4. Exudation does not Cocholidinium (1), Cryptodinium (1), Dinophysis (2), have a statistically significant relationship with cell size. Diplopelta (1), Diplopsalopsis (1), Gambierdiscus (2), In contrast to growth and photosynthetic processes, Gonyaulax (5), Gymnodinium (5), Ostreopsis (4), growth and photosynthetic efficiencies are independent Phaeopolykrikos (1), Podolampas (2) Prorocentrum (5), of cell size. The size-dependence of light absorptive Protoperidinium (10), Pyrodinium (1), Pyrophacus (3), properties provides a mechanism to explain the and Scrippsiella (3). The diversity of dinoflagellates is anomalous size scaling exponents associated with compared between six Pelican Cays oligothrophic anabolic rates. The robust statistically significant habitats with four mesotrophic mangrove habitats, part relationships between cell size and photosynthesis, of the Atlantic barrier reef-mangrove ecosystem. respiration, and growth was confirmed, but the magnitude of the size scaling exponent associated with 41 light-limited anabolic processes indicate that the PHYLOGENETIC ANALYSIS OF COCCOID allometric power law with an exponent of 3/4 does not PRASINOPHYTES (CHLOROPHYTA) USING 18S apply to photosynthetic organisms under all rDNA SEQUENCE DATA. environmental conditions. Fawley, M. W., Qin, M. & Yue, Y. Department of Botany, North Dakota State University, 43 Fargo, ND 58105 USA TAXONOMIC STATUS OF THE ANTARCTIC RED ALGA KALLYMENIA ANTARCTICA HARIOT 18S rDNA sequences have been obtained for 8 isolates Fredericq, S.1, Moe, R. L.2 & RamÍrez, M. E.3 of marine coccoid green algae. Phylogenetic analyses 1Department of Biology, University of Southwestern using maximum parsimony, maximum likelihood, and Louisiana, Lafayette LA 70508 USA; 2Herbarium, neighbor-joining methods indicate that prasinoxanthin- University of California, Berkeley, 94720-2465 USA; possessing coccoids are part of a lineage that includes 3Departamento de Botanica, Museo Nacional de other prasinoxanthin-possessing algae, such as Historia Natural, Casilla 787, Santiago Chile. Mantoniella, Pseudoscourfieldia, and Micromonas. Our results suggest that prasinoxanthin-possessing green One of the common encountered along the algae form a monophyletic group basal within the green Antarctic Peninsula and around the South Shetland algae. Our results are also in agreement with previous Islands is Kallymenia antarctica Hariot 1907. Detailed studies that have indicated that the Prasinophyceae as a morphological studies based on recent collections from whole are not monophyletic. King George Island in the South Shetland Islands were undertaken to characterize the vegetative and 42 reproductive morphology of this species and to assess its SIZE-DEPENDENCE OF METABOLIC PRO- taxonomic placement. The sequence of the chloroplast- CESSES IN MARINE DIATOMS (BACILLARI- encoded rbcL gene was compared with sequences from OPHYCEAE) UNDER LIGHT-LIMITING other red algae worldwide. Morphological and CONDITIONS molecular data indicate that the species is misplaced in Finkel, Z. V. Kallymenia, and point to the genus Sarcodia Department of Biology, Dalhousie University, Halifax (Sarcodiaceae, Gigartinales) as an appropriate NS B3H 4J1 Canada placement. 18 ABSTRACTS

from the microalga, Dunaliella salina, can be counted 44 as one of the successes. In recent years the industry has GENETIC DIVERSITY OF GREEN LICHEN matured and consolidated so that there is considerable PHOTOBIONTS AND EVOLUTION OF GROUP I cooperation between producers and more information INTRONS IN LICHEN SYMBIOSIS about their operational details. This has been crucial in Friedl, T.1 & Bhattacharya, D.2 light of the research results on the relationship of 1University of Kaiserslautern, Kaiserslautern Germany; carotenoids (especially beta-carotene) to human nutrition 2Department of Biological Sciences, University of Iowa, and disease over that time. The presentation will Iowa City, IA 52242 USA compare and contrast three of the largest producers: Nutrilite/Amway in southern California, Betatene in Members of the most abundant lichen algae, Trebouxia Australia, and Nature Beta Technologies in Israel. spp., as well as non-lichenized taxa of the green algal Comparisons will be made in the areas of algal strains, class Trebouxiophyceae are particularly rich in SSU medium, growth systems, harvesting, extraction, rDNA group I introns. Phylogenies inferred from product formulation and marketing. All are different, intron sequences were consistent with rDNA yet all are successful. What lessons can be learned to phylogenies of free-living trebouxiophytes help move other algal product ideas from the laboratory demonstrating a stable vertical inheritance of the introns to industry? in these algae. To investigate the relationships between the evolutionary histories of group I introns and the 46 genomes in which they reside, ITS rDNA sequences DETECTION OF THE TOXIC PFIESTERIA were determined for various strains and species of COMPLEX: A TECHNIQUE COMPARISON Trebouxia. Secondary structure models were used to Glasgow, H. B., Burkholder, J. M. & Hannon, E. K. refine the alignment of ITS and intron sequences. Department of Botany, North Carolina State University, These analyses suggest that introns which were Raleigh, NC 27695 USA vertically inherited among the free-living members of the Trebouxiophyceae are often laterally transferred Two methods are currently in use for culturing the when these algae become lichenized. Lichenization may ichthyotoxic Pfiesteria species "complex": toxic stages facilitate lateral transfer among the bionts due to their and species are detected using bioassays with live fish in intimate cell-to-cell contact within the lichen thallus. biohazard III facilities or, alternatively, nontoxic stages Phylogenetic and secondary structure analyses of the (as well as other mixotrophic species) are cultured using ITS sequences revealed a clear division of species algal prey. We compared zoospore production for previously attributed to the genus Trebouxia into two Pfiesteria piscicida and a second toxic Pfiesteria-like genera, Trebouxia and Asterochloris. For Trebouxia species (thus far, more weakly toxic and not yet spp., a distinction into four lineages of closely related formally named) using these two culture methods. species is resolved. These evolutionary relationships are Eight field samples from Chesapeake Bay and the in agreement with morphology and ultrastructure. Also, Albemarle-Pamlico were sub-aliquoted (n=3), and a considerable intraspecific variation was found and may subsamples were cultured with fish or with cryptomonad be correlated with geographic isolation and/or with prey over a 8-week time series. At least 100 cells different types of mycobionts with which the prepared with suture-swelling procedures were rotated photobionts are associated. to determine plate arrangement for morphospecies identification (ca. 2,500 cells screened over 2.5 days per 45 replicate). In 7 of 8 comparisons, the fish bioassay CAROTENOIDS FROM DUNALIELLA: A TRUE yielded only P. piscicida; in 1 case, a mix of P. ALGAE BUSINESS piscicida (60%), the 2nd toxic Pfiesteria-like species Gellenbeck, K. (10%), and Gyrodinium galetheanum (20%) occurred. Rehnborg Center for Nutrition and Wellness, Nutrilite By contrast, algal bioassays consistently yielded species Division, Amway Corporation, Lakeview, CA 92567 mixes that were dominated by various nontoxic species USA or by the second potentially toxic Pfiesteria-like species, with P. piscicida less common or not detected. The Since the 1950's there have been numerous efforts to data indicate that (i) the algal assay is not reliable for turn the promise of algal productivity and biochemistry detecting P. piscicida; and (ii) under the culture into real businesses. Not surprisingly, this has resulted conditions used, P. piscicida outcompetes other algae in in more failures than successes. Carotenoid pigments the presence of live fish, whereas the 2nd potentially ABSTRACTS 19 toxic Pfiesteria-like species and other mixotrophic Tertiolectae) was studied by RFLP. The DNA was dinoflagellates outcompete P. piscicida for algal prey. obtained from unialgal cultures and after PCR amplification, the ITS was, in some cases, further 47 purified using a DEAE-cellulose NA45 membrane. The TRACES OF POSSIBLE TRANSPOSON ORIGINS ITS fragment from each strain was single and double OF RED ALGAL PLASMIDS. digested with the following endonucleases: Ava II, Ban Goff, L. J. & Moon, D. A. II, Bsr I, Dde I, EcoRV, Hae III, Hha I, Hind III, Hinf Department of Biology, University of California at I, Msp I, Pvu II and Sty I. A cluster analysis was Santa Cruz, Santa Cruz, CA 95064 USA assessed based on the presence or absence of bands generated by RFLP, using the NTSYS software Many red algae harbor circular DNA plasmids in their package. A genetic map of the ITS was also performed cells. Recent in situ PCR localization studies have for each strain. Even though the lentgh of the fragment shown that the plasmids of Gracilaria and was the same for most of the strains (ca. 680 bp), the Gracilariopsis reside in host nuclei. They are of restriction patterns obtained showed variable fragment interest because of their potential use as shuttle vectors divergencies within and among species. Except for the for genetically altering red algal genomes. Red algal strain CCMP 1303 of D. salina which exhibited an ITS plasmids occur at very high copy number („100 copies region ca. 180 bp shorter than any of the taxa studied per cell), they are highly conserved at the species level and a restriction pattern also completely different, the and generally two or more plasmids co-reside in host ITS region appears to be an appropriate genetic marker cells. This is the case in Chilean Gracilaria chilensis to discriminate strains within D. salina. An unexpected which harbors both Gch3937 (GC1) and Gch3827 similarity of the restriction pattern was found between 2 (GC2). However, G. chilensis from New Zealand strains of D. parva and one strain of D. tertiolecta, even harbors only a single plasmid, Gch7220. Analysis of more close than among the strains of D. salina. The the sequence of Gch7220 shows that this plasmid is a genetic polymorphism found among taxa will be chimera of the two plasmids present in the Chilean discussed in term of inherent genetic variation and population. The entire Gch3937 plasmid has been erroneous identification of some strains coming from inserted into a conserved ORF of Gch3827 to form the culture collections. larger Gch7220 plasmid. The formation of the chimeric plasmid appears to have involved a homologous 49 recombination event between a short 70 bp region of BIOGEOGRAPHY OF THE CYANIDIACEAE DNA. Recombination results in a crossover between (RHODOPHYTA) BASED ON 18S RIBOSOMAL the two plasmids at the insertion point. As a result, RNA GENE SEQUENCE DATA Gch3827 is positioned between the two homologous Gross, W., Heilmann, I. & Lenze, D. regions and the sequence of Gch3827, immediately Institut für Pflanzenphysiologie und Mikrobiologie, adjacent to these homologous regions are an exact repeat Freie Universität Berlin, Königin-Luise-Str. 12-16, of CTTT and this repeat flanks a short 5 bp inverted 14195 Berlin, Germany repeat sequence: CTTAG and CTAAG. This feature - the presence of flanking short exact copies bordering Volcanic areas with pH-values ranging from 0.5 to 4 short inverted repeat sequences - is a hallmark of and temperatures up to 56 °C are inhabited by three transposable elements following insertion events. unicellular red algae: Cyanidioschyzon merolae, Cyanidium caldarium, and Galdieria sulphuraria. 48 These highly acidic habitats are scattered all over the GENETIC POLYMORPHISM IN THE ITS world and are usually very small. Because all three red REGION OF 15 STRAINS OF DUNALIELLA algae are acido- and thermophilic and will not tolerate Gonzalez, M. A.1, Montoya, R.2, Valenzuela, P.2, desiccation, a distribution by wind or water seems very Santander, M.2 & Coleman, A. W.3 unlikely. Therefore, the various populations might have 1Departamento de Botánica, 2Departamento de Biologia been isolated for very long times. We investigated the Molecular, Universidad de Concepcion, Concepcion, biogeography of 10 isolates of these red algae by Chile; 3BioMed, Brown University, Providence, RI sequence comparison of the 18S RNA. A gene tree 02912 USA places C. merolae and C. caldarium in a sister clade to the Bangiales and to higher red algae. At the base of The ITS region of 15 strains of Dunaliella (13 this branch, the Galdieria-isolates form a separate belonging to the section Dunaliella and 2 to the section branch which further divides into four groups 20 ABSTRACTS representing different geographical areas. This indicates Horn Point Laboratory, Center for Environmental that at least the genus Galdieria developed several Science, University of Maryland, Cambridge, MD geographical races with significantly altered 18S 21613 USA sequences. Therefore, a long separate evolution of these isolates seems likely. We obtained the photosynthetic ciliate Mesodinium rubrum/Myrionecta rubra from an enrichment culture of 50 sea-ice/water collected in January 1996 from McMurdo QUALITATIVE AND QUANTITATIVE STUDY OF Sound, Antarctica. Since then, the ciliate has been o TROPICAL BENTHIC MACROALGAL grown in F/2 (20-30 psu) at 2.0 to 6.0 C under 10-100 POPULATIONS FROM COMMUNITIES UNDER mmoles photons m-2 s-1 irradiance. Under these ANTHROPOGENIC DISTURBANCE. conditions, Mesodinium reaches high densities Gurgel C. F. D.1,2 & Yoneshigue-Valentin Y.1 (>15,000 cells ml-1) only when periodically supplied 1Universidade Federal do Rio de Janeiro, Departamento with a polar cryptophyte as prey. A 20-day experiment de Botanica, Instituto de Biologia, Rio de Janeiro RJ was done to determine how feeding affects Mesodinium; 21941-900, Brazil; 2Department of Biology, University cell numbers and attributes were quantified by flow of Southwestern Louisiana, Lafayette LA 70504 USA cytometry and epifluorescence microscopy. After addition of cryptophytes on day 1, cryptophyte numbers This study was carried out on the Praia Rasa shore, were reduced by approx. 80% in 48 hours. Red and Buzios City (Cape Frio, Rio de Janeiro State, Brazil), orange fluorescence per Mesodinium cell increased 1.5 which has experienced a conspicuous increase of human fold during this period and remained constant for 14 activity during the last decade. The aim was to evaluate days. Treatments with cryptophytes exhibited a higher the anthropogenic impact on the region's macroalgal sustained growth rate (0.19 divisions day-1) than communities by comparing current data with (1) treatments without cryptophytes (0.09 divisions day-1). previously published results obtained before the After 4 to 6 days the forward scatter (indicator of size) establishment of human presence in the area, and (2) decreased 20% for the "fed" cells and remained lower along a pollution gradient. Techniques were conducted than the control treatment ("unfed" cells) for the in the Rhodophytan zone in three established sample remainder of the experiment. On day 14, more sites where a total of 97 macroalgal species were found. cryptophytes (10,000 cells ml-1) were introduced to the Qualitative and quantitative variation were detected in previously "fed" treatment and it was monitored for an local communities, especially at sites closer to the additional six days. Once again the cryptophytes were anthropogenic disturbance source. There, total algal substantially reduced within 24 hours and average cover values and species composition changes fluorescence per Mesodinium cell slightly increased. decreased, pollution-sensitive species such as Caulerpa These data suggest that Mesodinium periodically obtain racemosa disappeared whereas others, such as Ulva spp. plastids from cryptophyte prey rather than permanently increased in abundance. Total number of species and maintaining a reduced algal endosymbiont. These data reproductive index did not seem to have undergone also suggest that exposure to cryptophytes is necessary significant changes over the years. Cluster and factor for sustained rapid growth of this photosynthetic ciliate. analysis (FA) revealed that of the three sample sites, the two closest to the impacted area were influenced at the 52 same rate. FA further suggested that the main factor SPATIAL AND TEMPORAL VARIABILITY IN regulating community structure is still natural THE ABUNDANCE OF CORAL REEF disturbances, followed by human impact. Despite the MACROALGAE IN THE FLORIDA KEYS detected changes and observed alterations produced by Hanisak, M. D. & Overdorf, L. S. human activity in the area, the Praia Rasa shore is still Harbor Branch Oceanographic Institution, Fort Pierce, unpolluted. FL 34946 U.S.A.

51 There is increasing concern over what appears to be a GROWTH OF AN ANTARCTIC MESODINIUM major decline in coral abundance and health in the RUBRUM Florida Keys. Frequently, this decline has been Gustafson, D., Stoecker, D. K., & Van Heukelem, W. attributed to increased cover of macroalgae, which may F. be able to overgrow corals. However, there are few historical data which can be used to support or refute claims of major changes in the reef algal community and ABSTRACTS 21 limited understanding of spatial and temporal variability Harrington, M. B., Pinckney, J. L. & Paerl, H. W. in macroalgae abundance. The first attempt at a Institute of Marine Sciences, University of North synoptic "snapshot" view of benthic macroalgal Carolina at Chapel Hill, Morehead City, NC 28557 abundance along the Florida Reef Tract was made in USA 1995, as part of a multi-disciplinary Keys-wide cruise. Twenty coral reefs were sampled with photogrammetric "Nitrogen is nitrogen" is a common assumption when techniques. The coral reef algal community was relating nutrient inputs to structural and functional dominated by several species of Dictyota and Halimeda. alterations of natural phytoplankton communities. There was a large amount of inter-reef variability in However, nitrogen (N) inputs can come from many macroalgal abundance. More intensive sampling of sources which supply chemically distinct N compounds, permanent photo-quadrats at Molasses Reef, off Key including nitrate and ammonium. Since these different Largo, Florida, indicated substantial temporal compounds possess different bioreactivities, they may variability, including large differences among seasons, lead to physiologically distinct responses in years, and decades (1985 to 1988 vs. 1995 to 1996). phytoplankton communities. The Neuse River Estuary, The immediate causes for these large differences in NC is a chronically N-limited system experiencing spatial and temporal variability are unknown, although nutrient-driven eutrophication. N loading to the estuary both "bottom-up" (nutrients) and "top-down" is currently increasing with the relative proportion of (herbivory) controls are probably involved and have ammonium growing. To determine if this compositional been altered by anthropogenic activities. These shift in N supply causes a corresponding compositional activities may result in further changes in community (and accompanying functional) shift in the local structure of this reef system, with serious impact on phytoplankton community, we performed small-scale (4 ecosystem structure and function. liter) manipulative bioassays. Community responses (primary productivity, biomass, algal composition) to 53 nitrate and ammonium additions were measured over 48 PHYLOGENETIC RELATIONSHIPS WITHIN hours. Results show that the phytoplankton community THE RHODOPHYTA: THE UTILITY OF is N-limited. Preliminary analysis shows no significant NUCLEAR LARGE-SUBUNIT RIBOSOMAL DNA difference between N types. In turbid environments, SEQUENCE DATA however, ambient irradiance may additionally affect N Harper, J. T. & Saunders, G. W. uptake and utilization. Nitrate assimilation requires University of New Brunswick, Fredericton, NB, E3B more energy than ammonium assimilation. At high 6E1 Canada light levels, the difference in energetic cost is relatively As a tool for providing enhanced resolution in red algal small and may not significantly affect the use of one N molecular phylogenies, the utility of data generated from compound over another. At lower light levels, nuclear large-subunit (LSU) ribosomal DNA sequences however, energetic costs are more critical and the has not been adequately assessed. Prior work on other difference may cause a preference for ammonium over algal groups (e.g. the Dinophyta) has illustrated that other N compounds. Investigations are underway to within the LSU there are twelve divergent domains. It examine the interplay of low light levels with different is hypothesized that the increased variation in these N sources and the consequent impacts on phytoplankton domains may provide enhanced resolution at equivocal community dynamics. nodes within phylogenies inferred from more conserved coding regions (e.g. the SSU). We have determined the 55 LSU sequence for a number of red algae spanning the MULTIMEDIA PHYCOLOGY: DEVELOPING majority of rhodophyte higher-level lineages. These EFFECTIVE USES OF A DYNAMIC TEACHING data will be used to establish the utility of the LSU in TOOL assessing phylogenetic relationships within the Hintze, K., Sommerfeld, M. R., Roberson, R. W., & Rhodophyta and perhaps clarify evolutionary Stutz, J. C. relationships left inconclusive from other molecular Department of Plant Biology, Arizona State University, data. Tempe, AZ 85287 USA

54 People retain only 20% of what they see and 30% of ECOLOGICAL IMPACTS OF DIFFERENT what they hear, but they remember as much as 80% of FORMS OF NITROGEN ON ESTUARINE what they see, hear and "do" simultaneously. PHYTOPLANKTON COMMUNITIES Multimedia uses computers to present and combine text, 22 ABSTRACTS graphics, audio, and video to promote students' learning environmentally realistic levels and the potential for by providing them a format to "see, hear and do additive effects with the parent compound and other simultaneously." We are developing a series of herbicides remain unknown. The differential species multimedia programs to teach phycology by using response to these commonly occurring herbicides current research about the design of multimedia indicates that shifts in algal community composition may educational tools. The multimedia programs are be a predicted outcome of exposure to atrazine. intended to provide self-paced instruction and exploration by individual students, but can also be 57 projected in lecture and laboratory. The first program PHYLOGENETIC SYSTEMATICS AND to be completed focuses on the algal class BIOGEOGRAPHY OF THE GIGARTINACEAE Bacillariophyceae, commonly known as diatoms. After BASED ON rbcL SEQUENCE ANALYSIS AND using the diatom program in two phycology classes, MORPHOLOGICAL EVIDENCE. students were surveyed and interviewed to determine if Hommersand,M. H.1, Fredericq, S.2, & Hughey, J.1 their learning experience was enhanced. Students found 1Department of Biology, University of North Carolina, that after observing modified images which emphasized Chapel Hill, NC 27599 USA, 2Department of Biology, frustule structures in the multimedia program, they took University of Southwestern Louisiana, Lafayette, LA less time to find and observe these structures in 70504 USA laboratory samples. They also were able to visualize processes such as life cycles and reproduction better by Recent molecular and morphological studies largely studying the program's animations and video. Students' confirm the systematic conclusions presented earlier comments indicate they prefer a course that utilizes (Hommersand et al., l993, Hydrobiologia Vol. multimedia lessons in addition to traditional lecture. 260/261; l994, Botanica Marina Vol. 37). We Through the use of multimedia, our goal is to stimulate recognize the following: (1) a Chondracanthus clade, greater student interest in algae, as well as increase with two groups, one occurring primarily in the Western learning efficiency and student satisfaction. Pacific and by eastward distribution in the Atlantic Ocean, and a second occurring primarily along the coast 56 of South and North America and by westward EFFECTS OF ATRAZINE AND ITS distribution in the Atlantic Ocean; (2) a Gigartina clade METABOLITES ON FRESHWATER ALGAE consisting of paraphyletic taxa Rhodoglossum and Hoagland, K. D., Ingersoll, S. A. & Siegfried, B. D. Gigartina radula, and Gigartina occurring in cool School of Natural Resource Sciences & Department of temperate regions of New Zealand, Australia and South Entomology, University of Nebraska, Lincoln, NE Africa, with one species in Western Europe; (3) a 68583 USA Sarcothalia clade with one genus, Sarcothalia, distributed widely in the Southern Ocean; (4) a Despite the presence of the herbicide atrazine and its Chondrus clade consisting of the paraphyletic taxa metabolites in surface waters throughout the agricultural Iridaea, Chondrus canaliculatus, and Mazzaella midwestern United States, little is known of the toxicity distributed primarily along the coasts of South and of the metabolites to non-target organisms such as algae. North America, and Chondrus found in the western The acute toxicities of atrazine and its primary North Pacific with one species in the North Atlantic metabolites (desethyl- and disopropylatrazine) to eight Ocean; and (5) three undescribed monotypic genera: one species of freshwater algae representing both diatom and based on Gigartina alveata from New Zealand, one on a chlorophyte taxa were determined in the laboratory. plant from Tasmania (G. Kraft), and one on Gigartina Growth responses were monitored by fluorescence every skottsbergii from southern South America and two days for 15 days. Deisopropylatrazine was Antarctica. Clades identified in rbcL trees correspond approximately 25 to 400 times less toxic than the parent to taxa circumscribed on the basis of cystocarp anatomy, compound, whereas desethylatrazine was 12 to 80 times particularly the structural relationship between less toxic to several of the algae tested. The pattern of developing gonimoblasts and surrounding gametophytic differential toxicity among algal taxa was similar for the nutritive filaments. Tetrasporangial characters, while metabolites and parent compound in that diatoms were often useful for recognizing genera, are less reliable as generally less sensitive than the green algae assayed. indicators of taxonomic affinity. Each clade contains a Thus, effective concentrations of atrazine metabolites range of similar morphological types adapted to are well above those typically found in surface waters, particular environments and gross morphology is useful however the effects of long-term exposures to ABSTRACTS 23 taxonomically primarily at species and infraspecific harveyanus, C. spinosus, C. tepidus) and seven from levels. the Gulf of California (C. acicularis, C. intermedius, C. johnstonii, C. macdougalii, C. pectinatus, C. teedii, C. 58 tepidus). Nearly ten additional taxa have been described SIZE SCALING IN MOTILITY OF COLONIAL under Gigartina, but these are traditionally treated as VOLVOCALEAN ALGAE synonyms. Sequence analysis of the rbcL gene Hoops, H. J., Armstrong, D., & Ray, S. J. (RUBISCO) and ITS (Internally Transcribed Spacer) 1, Biology Department, State University of New York at 2, and 5.8S regions, combined with a morphological Geneseo, Geneseo, NY 14454 USA study of vegetative and reproductive structures were employed to investigate phylogenetic relationships We studied motility in Pandorina morum, Yamagishiella among the species. Eighty sequences were obtained of unicocca, rousseletii and Volvox carteri to the rbcL and ITS regions, representing geographically determine the relationship between colony size and widespread populations. The phylogenetic trees inferred swimming speed. Each alga was videotaped as it swam from the two molecular data sets were congruent. towards an artificial light source. For each species, the Ecads of C. exasperatus were unresolvable and sister to average velocity remained fairly constant over a variety the C. spinosus complex. Sequences of C. acicularis of light intensities examined. At the low Reynolds (distinct from C. acicularis from Europe), C. johnstonii, numbers typical for microorganisms moving through C. macdougalii, and C. pectinatus from the Gulf of water, resistance is almost completely due to viscous California were identical. Reinvestigation of these four drag. Stokes' law predicts that a sphere being pulled species showed that they were continuously variable in through the water experiences viscous drag that is their morphology. Chondracanthus intermedius from directly proportional to both the velocity and the radius. the Gulf equated to C. intermedius from Japan. However, the number of cells at the surface of a Chondracanthus corymbiferus, C. harveyanus and C. spherical colony should vary as the square of the canaliculatus were strongly supported taxa. External colonial radius. The propulsive force that must and internal vegetative and reproductive morphology, overcome the drag is presumably correlated with cell ecology, and texture were used to characterize species. number. Since an increase in radius relates to an Our data supports the continued recognition of the exponential increase in cell number but only a linear Pacific taxa listed above, but only two of those recorded increase in drag, we expect that species with larger for the Gulf of California. colonial diameters will swim faster. P. morum, Y. unicocca, V. rousseletii and V. carteri had average 60 diameters of 0.034, 0.040, 0.18 and 0.24 mm WINTER FLAGELLATE COMMUNITIES IN respectively and rates of progression of 0.27, 0.26, DIFFERENT TYPES OF SEA ICE IN THE ROSS 0.46, 0.54 mm sec-1. respectively. Thus, size is SEA, ANTARCTICA positively correlated with increased swimming speeds, Ikavalko, J. but the differences are not as great as would be expected Institute of Marine Sciences, University of California from Stokes' law alone. Santa Cruz, Santa Cruz, CA 95064, USA Sea ice plays an important role in modifying ecosystem structure in the all ice covered sea regions. Ice cover does not only offer a platform for animals to migrate, feed and reproduce on but it may also serve as a food source or a refuge for a variety of pelagic organisms. 59 Sea ice supports highly diverse, often diatom dominated A SYSTEMATIC STUDY OF SPECIES OF microbial communities, where both photo- and CHONDRACANTHUS (RHODOPHYTA, GIGAR- heterotrophic nanoflagellates (e.g. crypto-, prasino-, and TINALES) FROM PACIFIC NORTH AMERICA haptophytes, dino- and choanoflagellates) are Hughey, J. R. & Hommersand, M. H. commonly encountered. The winter survival of pelagial Department of Biology, University of North Carolina at (under-ice) consumers, e.g. Antarctic krill Euphausia Chapel Hill, Chapel Hill, NC 27599 USA superba is largely dependent on the availability (quality and quantity) of food items living associated with sea Twelve species are recognized for Chondracanthus from ice. This, in turn, is much related to the structure of sea Pacific North America: six from the Pacific Ocean (C. ice. This presentation highlights the first results of a canaliculatus, C. corymbiferus, C. exasperatus, C. study that was made in the Ross Sea (Antarctica) in 24 ABSTRACTS

May-June '98 and which aimed to relate observed Johnsen, G.1, Dalloekken, R.1, Aure, J.2 & Skjoldal, H. differences in microbial community structure to different R.2 ice types (frazil, columnar etc.), and stages of new ice 1Norwegian University of Science and Technology, formation (grease, nilas and pancake ice), with a Trondhjem Biological Station, N-N-7034 Trondheim. particular emphasis on flagellate diversity. Norway; 2Institute of Marine Research, N-5024 Bergen- Nordnes. Norway 61 HIS-ASP SIGNAL TRANSDUCTION IN A toxic phytoplankton bloom, dominated by CHLOROPLASTS OF HETEROSIGMA CARTERAE Chrysochromulina leadbeateri, developed in the o Jacobs, M. A., Connell, L. B. & Cattolico, R. A. Ofotfjord-Tysfjord area in North Norway (68 N) in the Department of Botany, University of Washington, middle of May and ended in the end of June 1991 in the Seattle, WA 98195 USA Vestfjord and adjacent fjord areas. The bloom was transported with outflowing low-salinity water along the Gene expression in chloroplasts may be controlled at Lofoten Islands where it caused losses of about 750 each step, from transcript initiation through post- metric tons reared fish, mainly Atlantic salmon. A translational polypeptide modification. Cyanobacteria significant amount of chlorophyll c3 was present in the use signal transduction pathways involving His-Asp water masses and yielded high in vivo absorption and phosphorelay signaling, often between “sensor kinase” fluorescence excitation signals at 470 and 585 to 590 and cognate DNA-binding “response regulator” nm, respectively. Chlorophyll c3-containing species proteins, to regulate transcription. This His-Asp system comprises some of the most common bloom-forming has yet to be demonstrated functionally in chloroplasts. and harmful phytoplankton species in European waters, A putative chloroplast-encoded His-Asp transcriptional i.e. species from the genera Chrysochromulina, response regulator gene (trg1) has been identified in the Prymnesium, Phaeocystis, Gyrodinium and estuarine raphidophycean alga Heterosigma carterae, as Gymnodinium. Light and electron microscopy verified well as in several rhodophytes, and a glaucophyte. The that C. leadbeateri often was accompanied with other Heterosigma trg1 open reading frame is approximately Chrysochromulina species and peridinin-containing 0.7 kb in length, contains no introns, and yields a dinoflagellates. Bio-optical characteristics, conceptual translation product of 231 amino acids (26.8 pigmentation, cell chemistry and growth rates of an kDa). Homology searches suggest that Heterosigma isolate of C. leadbeateri obtained from this bloom, trg1 has an ompR-like identity within the DNA-binding grown under high- and low-light conditions in His-Asp response regulators. Amino acid residues laboratory, are given for comparison with field data conserved among all ompR-like response regulators are consisting of spectral irradiance, salinity, temperature, identical in trg1. Quantitative competitive RT-PCR [nitrate], [phosphate], [silicate], [chlorophyll a], showed that Heterosigma trg1 is expressed at low levels [oxygen], light stimulated in situ fluorescence, bio- (5 mg g-1 total RNA). In contrast, psbA (positive optics, pigmentation, and species composition/numbers. control) transcript is abundant (60 mg g-1 total RNA). A possible scenario for the development of this bloom Cell cycle analysis showed that psbA abundance was the enhanced nutrient concentration during the oscillates in response to light (as has been previously winter 1990-91 in the Ofotfjord due to overwintering of demonstrated by both northern analysis and run-on approximately 1 million tons of herring from 0-250 m transcription assays in Heterosigma). Trg1 mRNA depth which may have sustained a large stock of levels, however, were invariant. We hypothesize that a mixotrophic C. leadbeateri in early spring. His-Asp phosphorelay mechanism may affect chloroplast genome transcription in a manner similar to 63 bacterial signal transduction pathways in which “sensor PARTHENOSPORES IN OEDOCLADIUM kinase” and cognate “response regulator” proteins (OEDOGONIALES, CHLOROPHYTA) interact. Juarez, A. B., Alberghina, J. S., & Velez, C. G. Departamento de Ciencias Biologicas, Facultad de 62 Ciencias Exactas y Naturales, Universidad de Buenos PHOTOPHYSIOLOGY & ENVIRONMENTAL Aires, Buenos Aires, Argentina CONDITIONS DURING A TOXIC BLOOM OF CHRYSOCHROMULINA LEADBEATERI In Oedogoniales, parthenospores develop as thick walled (PRYMNESIOPHYCEAE). spores from non fertilized egg cells. These spores, as well as oospores (sexual in origin), are usually deep ABSTRACTS 25 orange, with a high content of starch and oil. cell orientation. Together, these laboratory and Parthenospores had been registered only in Oedogonium modeling approaches support the formulation of new and Bulbochaete. Working on cultures from Argentine hypotheses that will be tested on natural populations in material of Oedocladium carolinianum, it was observed planned field campaigns like the ECOHAB:Florida that oogonia may form two kind of spores: spores program. Eventually, the field results will support the similar to oospores (most frequent), and spores with formulation of a realistic physical context for the atypical features resembling oospores of Oedocladium behavioral models. protonema Stahl, the type species. In the present work, it is experimentally demonstrated that the unusual type 65 of spores in Oedocladium carolinianum (two strains) A COMPARISON OF SHALLOW AND MID- and Oedocladium cirratum are parthenospores. Their DEPTH BENTHIC MACROALGAL morphology as well as some germination details are COMMUNITIES ON A CARIBBEAN CORAL described. Evidence of cell polarity in egg cells is REEF presented. Finally, taxonomic significance of these Keeney, T. S. & Lehman, R. L. observations is discussed. Texas A&M University, Corpus Christi Center for Coastal Studies, Corpus Christi, TX 78412 USA 64 ECOPHYSIOLOGICAL INFLUENCES ON Two benthic coral reef macroalgal communities were DINOFLAGELLATE TRAJECTORIES investigated in the vicinity of Boca Paila, Sian Ka'an Kamykowski, D.1, Milligan, E. J.1, Reed, R. E. 1, Liu, Biosphere Reserve, Quintana Roo, Mexico. The well- W. 1, Yamazaki, A. K.2, & Janowitz, G. S.1 developed reef system may be described as fringing or a 1Department of Marine, Earth & Atmospheric Sciences, small barrier reef. An assessment of the species North Carolina State University Raleigh, NC 27695 composition of benthic macroalgae in a patch reef field USA; 2Nippon Institute of Technology Japan (approximately 4.5 meter depth) and mid-reef spur and groove area (approximately 18 meter depth) was The motility of dinoflagellates, a group responsible for conducted by nondestructive photogrammetric methods many Harmful Algal Blooms (HABs), often is utilizing a modified line transect. Cover, densities and implicated in the formation of species specific cell frequencies of benthic macroalgal species from the two aggregations, but information on cell trajectories under zones were compared. Species richness and diversity natural conditions is limited. Swimming speed, which indices are provided along with a taxonomic checklist. together with orientation defines a cell's velocity, varies with cell size and with changes in environmental 66 variables like light intensity, temperature and salinity. A 20-YEAR STUDY OF ASCOPHYLLUM The even more obscure orientation component of NODOSUM POPULATION DYNAMICS NEAR A velocity traditionally is attributed to geotaxis or HEATED EFFLUENT IN EASTERN LONG phototaxis, but accumulating evidence suggests that a ISLAND SOUND. cell's biochemical state as determined by cell division Keser, M., Foertch, J. & Swenarton, J. and subsequent light and nutrient exposure may Northeast Utilities Environmental Laboratory, influence the strength and possibly the sign of these Millstone Nuclear Power Station, Waterford, CT 06385 taxes. For example, one laboratory study with USA Gymnodinium breve suggests that the strength of negative geotaxis increases as cellular lipid concentration Ascophyllum nodosum populations exhibit easily decreases, while another laboratory study with quantifiable responses to changes in water temperature, Heterocapsa illdefina suggests that the strength of making population studies a useful biomonitoring tool negative geotaxis increases as cell diameter decreases. for assessing effects from heated effluents. Growth and Mathematical models based on the principles of adaptive mortality characteristics of four tagged populations (two behavior provide a test bed for these laboratory results thermally impacted, and two unimpacted) in the vicinity in the context of light and nutrient availability of Millstone Nuclear Power Station (MNPS) have been representative of field conditions. Currently, these monitored over a 20-year period (1979 to 98) as part of behavioral models monitor the biochemical status of a comprehensive ecological monitoring program. A individual cells or subpopulations and combine Gompertz growth curve was fitted to monthly information on internal cellular state with the stimulus Ascophyllum tip length data using non-linear regression provided by external environmental cues to determine methods. Parameters derived from this function were 26 ABSTRACTS used to describe and statistically compare annual growth lectins were partially reversed (to 80 to 90% of and growth rates. Mortality, or thallus breakage, was controls) by addition of complementary carbohydrates. assessed by examining tag loss patterns. During exposure to moderate thermal addition (<5 oC above 68 ambient), the growing season began earlier and growth USING SUPA TO CHARACTERIZE PHOTO- over the year was significantly higher than at reference SYNTHETIC PROCESSES OF HABS sites farther away. Higher levels of thermal input Kirkpatrick, G. J.1, Reed, R. E.2, & Kamykowski, D.2 o reduced growth rates when temperatures reached 27 C 1Mote Marine Laboratory, Sarasota, FL 34236 USA; o (7 to 9 C above ambient), and total population mortality 2Department of Marine, Earth & Atmospheric Sciences, o was observed when temperatures exceeded 30 C (>10 Department of Marine, Earth & Atmospheric Sciences, o C above ambient). Aside from this mortality event, no North Carolina State University Raleigh, NC 27695 relationship between power plant operations and USA mortality was found during years of sublethal impacts. Rather, mortality was associated with natural During in situ deployments of the Self-contained, environmental stress from storm-driven waves, or in Underwater Photosynthesis Apparatus (SUPA), net several instances, with human intervention (vandalism). carbon and oxygen productivity of contained phytoplankton samples were measured on minute time 67 scales for up to 48 hours. The samples were contained FERTILIZATION IN AGLAOTHAMNION within one-liter quartz chambers providing a means to OOSUMIENSE (CERAMIACEAE, RHODO- track the responses of known populations. Blooms (or PHYTA) MONITORED BY THE USE OF FITC- cultures) provided productivity signals that were optimal LECTINS for short period measurements because of the highly Kim, G. H. & Kim, S-H. concentrated samples. The results to be presented will Department of Biology, Kongju National University, contrast the productivity differences between two Shingwandong, Kongjushi, Chungnam 314-701Korea phytoplankton species, one representing HAB species (Gymnodinium breve) and one representing non-HAB, The binding of fluorescein isothiocyanate (FITC) high biomass, species (Thalassiosira pseudonana). conjugated lectins to gametes of Aglaothamnion Gymnodinium breve produces blooms in the surface oosumiense Itono during the fertilization was studied by layer of the Gulf of Mexico and the Southeastern U.S. the use of confocal microscope. The physiological Atlantic coast. In these regions this surface dwelling effects of lectins and carbohydrates on gamete binding species is exposed to intense irradiance during summer were also examined. Four different lectins, and therefore was expected to cope with experimental concanavalin A (ConA), Soybean agglutinin (SBA), exposures in surface waters of the West Florida coast. Dolichos biflorus agglutinin (DBA) and wheat germ Thalassiosira pseudonana had been used successfully in agglutinin (WGA) bound to the surface of spermatia, a number of laboratory and field studies with SUPA, but each lectin labelled different region of the several in the Gulf of Mexico. Under high natural spermatium. SBA and DBA bound only to the irradiance conditions in SUPA, G. breve's net spermatial appendages but ConA bound to all the productivity declined rapidly and showed no acclimation spermatial surface except spermatial appendages. WGA response over the course of the deployment. In labelled narrow region which connects spermatial body contrast, T. pseudonana showed only moderate decline and appendages. During the fertilization, the ConA and in net productivity under high irradiance, recovered WGA specific substances on the spermatial surface rapidly when irradiance declined and showed an moved towards the area contacting with trichogyne and acclimation response. A better understanding of the accumulated on the surface of fertilization canal. response of G. breve to fluctuating, high irradiance Spermatial binding to trichogynes was inhibited by pre- exposure will help describe the processes leading to incubation of spermatia with SBA or ConA, while bloom formation, persistence and demise. trichogyne receptors were blocked by the complementary carbohydrates, D-glucose or N-acetyl D- 69 galactosamin, respectively. WGA and DBA as well as EFFECTS OF DESMARESTIA VIRIDIS ON their complementary carbohydrates had little effect on SUBTIDAL COMMUNITY STRUCTURE: the gamete binding. The inhibitory effects of ConA and INHIBITION OF URCHIN MOVEMENT AND SBA was much more enhanced when two lectins were ALGAL RECRUITMENT applied at the same time. The inhibitory effects of both Konar, B. ABSTRACTS 27

University of California at Santa Cruz, Santa Cruz, CA The remainder separates in an Atlantic clade with sister 95064 USA taxa H. tuna and H. discoidea and a Pacific clade also with H. discoidea. Thus, H. discoidea is paraphyletic. Experimental manipulations were used to evaluate the Amphi-Pacific samples of H. discoidea are closely effect of Desmarestia viridis on community structure on related and so are amphi-Atlantic ones indicating that subtidal pinnacles at Shemya Island in the western these populations disperse easily within an ocean Aleutian archipelago. Pinnacle tops had dense, annual system. Sections Opuntia and Micronesicae together algal-dominated kelp stands, whereas the sides and form a clade. All species therein are monophyletic. bottoms had little to no foliose cover. In contrast, sea Samples of H. opuntia from the Atlantic and Indo-West urchin densities were significantly higher on the bottoms Pacific are found in sister clades with Pacific H. fragilis and sides of pinnacles, and were seasonally variable on as next nearest neighbor. The Atlantic clade with H. the tops. Highest urchin densities on the tops of goreauii and H. copiosa is sister to similar Pacific pinnacles occurred in the fall as algal cover declined. In species. The link of the Halimeda phylogeny to the summer, removal of various combinations of vicariant events suggests that the extant taxa in this macroalgae from the pinnacle tops resulted in an genus diversified ca. 20 million years ago. The fossil increase in urchin density when D. viridis was excluded. record dates back well into the Cretaceous. The earlier As urchins moved to the tops from the sides and history could be due to several cycles of adaptive bottoms, after D. viridis was removed, the urchins were radiation and near-extinction. capable of eliminating the rest of the foliose algal cover. Artificial structures, which imitated D. viridis, were 71 placed on pinnacle tops and inhibited urchin movement. LABORATORY OBSERVATIONS OF This inhibition of urchin movement by D. viridis allows IMMUNOSUPPRESSION BY CYANO-BACTERIA kelp stands to persist through the year on pinnacle tops. Korpi, K. D. Although D. viridis has a positive effect on the entire K² Research, Las Vegas, NV 89129 USA kelp stand by protecting it from the negative effects of grazing urchins, it also had a negative effect on other Based on public health agency observations and previous foliose algae through competition for space. Removal research, environmental cyanobacteria can elevate of D. viridis and urchins from pinnacles resulted in an populations of other, similar classes of organisms increase of other algal species. However, without D. consisting of molds and fungi. While incidence may be viridis, the kelp stands would not be able to persist over due to factors providing cyanobacteria necessary the years in the presence of urchins. minerals and dissolved organic matter, it is not our research subject. Our studies concentrate on 70 undiagnosed, long term illnesses with potential for EVOLUTION OF SECTIONS IN HALIMEDA IS cyanobacteria as the causative vector. We continue to LINKED TO TETHYAN-PANAMANIAN investigate a trend that normally non- pathogenic, CLOSURE EVENTS. resilient secondary infections could be the consequence Kooistra, W. H. C. F., Calderón, M. & Hillis, L. W. of cyanobacteria. Focusing on identification of a Smithsonian Tropical Research Institute, Unit 0948, narrow rift in immune defenses, our research reviews APO AA 34002 USA. new and historically misidentified relationships. Our first goal is to bring about revised educational guidelines Partial 18SrDNA sequences, including a 102 base pair designed to replace referral of patients with legitimate, insertion, and the complete ITS region were used to uninvestigated symptoms to the care of psychoanalysts. infer phylogenies among 60 samples comprising all As our investigation shows, numeric incidence has been sections in Halimeda. Results show linkage with concealed by relegating symptoms of infection into Tethyan or Panamanian closure events that separated the categories restricting empirical investigation and tropical Indo-Pacific and Atlantic. Section Rhipsalis is masking recognition of cyanobacteria as a pathogen. monophyletic; its basal dichotomy separates Indo-Pacific The Phycological Society of America has provided and Atlantic taxa. Subsequently, similar morphologies invaluable culture methodology and studies enhancing evolved independently in both ocean systems. Atlantic identification of cyanobacteria. Continued research over H. monile and Pacific H. cylindracea are five years has disclosed information into complex morphologically similar but are not sister taxa. Section relationships cyanobacteria have with secondary Halimeda is paraphyletic. Sister species H. lacrimosa mycoses. This finding should indicate a need for and H. gracilis differ from all other representatives. reduced diagnoses of neurologic disorders and to return 28 ABSTRACTS treatment to efficacious, mainstream medicine. The 1Department of Biology, 2Department of Anatomy, colonizing nature of cyanobacteria and affinities to Colorado State University, Fort Collins, CO 80523 USA secondary infections including black molds (Aureobasidium, Bipolaris), yeasts (Hansenula, The ultrastructure and systematics of two new red Candida) and fungi (Aspergillus, Penicillium), have colored freshwater cryptomonads, (= demonstrated a link with aflatoxin producing organisms ) ovalis and hanrattyi sp. nov., likely to lead to the conclusion that all metastatic cancers will be discussed. Pyrenomonas ovalis has the generic spring from a single, spontaneous source. Our research characteristics described for marine continues investigation into health risks and potential Rhodomonas/Pyrenomonas spp. It has a short furrow, a serologic correlation. deep gullet, square inner periplast plates with beveled corners, a mucilagenous surface periplast component, a 72 single chloroplast with two lobes connected by a MOLECULAR AND MORPHOLOGCAL pyrenoidal bridge, and a nucleomorph located in an EVIDENCE FOR BRYOPSIS (CHLOROPHYTA) indentation of the pyrenoid. Storeatula, which also has SYSTEMATICS been described from marine waters only, has a single Krellwitz, E. C. inner periplast sheet and a mucilaginous surface Department of Botany, Duke University, Durham, NC periplast component. Cells lack a furrow, they have a 27708 USA gullet, they have a bilobed chloroplast connected by a pyrenoid and they have a nucleomorph located in an A phylogenetic analysis of sequences of the intron indentation of the pyrenoid. Even though a furrow is located in the chloroplast psbT gene from over 70 lacking, there is a scalariform furrow plate that lines the specimens of Bryopsis indicates that there are four well- gullet, suggesting that the gullet originated from a resolved clades along the east coast of the United States. fusion of furrow folds. This freshwater Storeatula These clades differ significantly in either the seasonality basically possesses the same features as the marine or latitudinal distribution of their US members. species but is designated as S. hanrattyi because of its Statistical analysis of nine morphological characters freshwater occurrence. indicates that a significant portion of the variance in several of those characters can be attributed to 74 differences among psbT clades. A unique collection THE POSSIBLE ADAPTIVE ADVANTAGE OF from the Florida Keys included specimens belonging to CHLOROPLAST E. R. - THE ABILITY TO two separate clades growing within a few meters of each OUTCOMPETE AT LOW DISSOLVED CO2 other, but showing very distinct morphologies. They CONCENTRATIONS. represent the equivalent of a common garden experiment Lee, R. E.1 & Kugrens, P.2 and further support the hypothesis that there are 1Department of Anatomy & Neurobiology; 2Department genetically based morphological differences between & Biology, Colorado State University, Fort Collins, CO these clades, but the differences are frequently eclipsed 80523 U.S.A. by the high level of phenotypic variation. The ecological and morphological data support the Algae with chloroplast endoplasmic reticulum apparently congruence of these molecular clades with species, but are able to grow at lower dissolved CO2 concentrations unfortunately the ranges of these characters are than those eukaryotic algae without chloroplast E.R.. continuous. They cannot be used as fixed field The dissolved CO2 is low in marine waters (at normal characters and the morphological data from type pH 8 of seawater, HCO-3 is 2000 mM while CO2 is 15 specimens is insufficient to positively identify any of the mM at 25oC). Thus, algal blooms in open oceans groups. Preliminary data suggests that sequences from usually consist of algae with chloroplast E.R. (usually topotype specimens may be able to associate species diatoms, dinoflagellates, prymnesiophytes, names with psbT clades. rhaphidophytes or such as Sargassum). Anthropomorphic increases in atmospheric CO2 should 73 result in increased dissolved carbon dioxide in open ULTRASTRUCTURE AND SYSTEMATICS OF oceans and an accompanying increase in eukaryotic TWO NEW FRESHWATER CRYPTOMONADS, algae that normally are growth limited by the low PYRENOMONAS OVALIS & STOREATULA dissolved CO2 (e.g. green and red algae). This increase HANRATTYI SP. NOV. in dissolved CO2, and decrease in algae with chloroplast Kugrens, P.1, Clay, B. L.1 & Lee, R. E.2 E.R., could be beneficial to humans since this should ABSTRACTS 29 reduce toxin-producing algal blooms. In freshwaters blooms are formed. Cell division in dinoflagellates is dissolved CO2 is more plentiful because of the lower pH frequently regulated by a circadian clock, with mitosis of freshwaters (at pH 1 virtually all of the dissolved phased to the light/dark cycle. In this study, we sought -3 carbon is in the form of CO2 and none as HCO ). to identify mechanisms which link the cell cycle to the Eutrophic freshwaters are commonly dominated by diel cycle. The dinoflagellate Amphidinium operculatum eukaryotic green algae that lack chloroplast E.R. Under is a useful model because its high division rate yields a these conditions of relatively high dissolved CO2, algae nearly synchronous population. Using flow cytometry, with chloroplast E.R. would be at a disadvantage and we found that the cell cycle of A. operculatum is phased only become abundant after a bloom of green algae or to the diel cycle, with S-phase beginning 7h and mitosis cyanobacteria had reduced the dissolved CO2 15h after the onset of light. Alterations of the light/dark concentration to a level where the green algae or cycle showed that cell cycle progression is phased by the cyanobacteria could not take up enough dissolved CO2 dark/light transition. In the more advanced alga, to compete. Anthropomorphic activities have resulted in Euglena, cAMP dependent signaling is believed to increased acidification of freshwaters with subsequent mediate circadian rhythms. Therefore, we investigated increases in green algal populations. the role of cAMP in circadian control of the cell cycle in A. operculatum. Measurement of intracellular cAMP 75 by radioimmunoassay revealed that cAMP levels in A. UTILIZING ALEXA 488 PHALLOIDIN TO operculatum varied on a diurnal basis, with minimum VISUALIZE ACTIN MICROFILAMENTS IN concentrations present at the onset of the light phase, ALGAE and concentrations increasing to a maximum level, Lee, T. F. & Arsenault, P. which occurred prior to the onset of dark. Biology Department, St. Anselm College, Manchester, Furthermore, the cAMP phosphodiesterase inhibitor NH 03102 USA IBMX acts in a dose dependent manner to inhibit cell cycle progression at G1/S, indicating that cAMP Cytoskeletal actin microfilaments play a role in many signaling is involved either in the dark/light transition or processes in eucaryotic cells, including cytoplasmic is directly involved in regulating S-phase entry. Current streaming, morphogenesis, and organelle movement. research is directed at elucidating the precise role of Visualization of F (filamentous)-actin in algal cells cAMP signaling in the cell cycle of A. operculatum. usually has employed fluorescein isothiocyanate (FITC) phalloidin or rhodamine phalloidin. These may have 77 several disadvantages, including rapid photobleaching PHYSIOLOGICAL BASES OF CELL GROWTH IN and masking of actin by pigment autofluorescence. We PFIESTERIA PISCICIDA demonstrate here that the new fluorescent probe Alexa Lewitus, A. J.1, Burkholder, J. M.2, Glasgow Jr., H. 488 phalloidin from Molecular Probes, Inc. (Eugene, B.2 & Glibert, P. M.3 Oregon, USA) appears to be an effective probe for 1University of South Carolina (AJL), Baruch Marine visualizing actin microfilaments in a variety of algal Laboratory, Georgetown, SC 29442 USA; 2 North cells. This probe is very bright and quite photostable, Carolina State University, Botany Department, Raleigh, and its emission spectrum minimizes interference from NC 27695; 3Univeristy of Maryland (PMG), Horn Point chlorophyll autofluorescence.We show actin Laboratory, Cambridge, MD 21613 USA microfilaments in nine green and one brown alga. The nutritional versatility of dinoflagellates is a 76 complicating factor in identifying potential links MECHANISMS THAT LINK THE CELL CYCLE between nutrient enrichment and the proliferation of TO THE DIEL CYCLE IN THE harmful algal blooms. For example, although DINOFLAGELLATE, AMPHIDINIUM dinoflagellates associated with harmful algal blooms OPERCULATUM (e.g. red tides) generally are considered to be Leighfield, T. A. & Van Dolah, F. M. phototrophic and use inorganic nutrients such as nitrate Marine Biotoxins Program, NOAA, National Ocean or phosphate, many of these species also have Service, &Graduate Program in Marine Biology, pronounced heterotrophic capabilities either as University of Charleston, Charleston, SC 29412 USA osmotrophs or phagotrophs. Recently, the widespread occurrence of heterotrophic toxic dinoflagellates has Mechanisms which regulate growth and reproduction in been documented in turbid estuarine waters. One such dinoflagellates are critical to understanding how algal species, Pfiesteria piscicida, has a relatively proficient 30 ABSTRACTS grazing ability compared to herbivorous protists of powders. In conclusion, we have successfully similar size, but also has an ability to function as a developed the large- scale production process for phototroph by acquiring chloroplasts from algal prey, a Chlorella using mixotrophic growth with glacial acetic process termed kleptoplastidy. The physiological acid as a C-source. Under our specific conditions of responses of P. piscicida to inorganic and organic culturing, harvesting and products processing, Taiwan nutrient additions were compared in strictly has become the world's greatest producer of Chlorella heterotrophic vs. kleptoplastidic cultures. When cells and products for health foods and specialty heterotrophic, P. piscicida responded to nutrients nutrition markets. indirectly (i.e. its growth rate was correlated with increased phytoplankton prey abundance), although 79 direct uptake of nutrients was detected. When PRELIMINARY PHYLOGENY OF THE MARINE kleptoplastidic, direct uptake of inorganic and organic RED ALGAL FAMILY DELESSERIACEAE nutrients was observed, and the uptake rates of certain (CERAMIALES, RHODO-PHYTA) substrates, such as urea, were relatively high compared Lin, S-M. to heterotrophic cultures. The results suggest that the Department of Biology, University of Southwestern response of P. piscicida to nutrient enrichment is Louisiana, Lafayette, LA 70504 USA. complex, and that several pathways of nutrient stimulation may be ecologically relevant, depending on The Delesseriaceae currently contains the two the relationship between nutrient quantity, nutrient subfamilies Delesserioideae and Nitophylloideae, quality, phytoplankton abundance, and P. piscicida's encompassing 22 Groups/Tribes, about 95 genera and nutritional state. 310 species. The two subfamilies were primarily distinguished by Kylin (1924) based on pattern of apical 78 growth, vegetative cell division, and procarp MIXOTROPHIC MASS CULTURING OF architecture. Uncertainties in many species in the CHLORELLA SPP. IN TAIWAN interpretation of morphological features and convergent Lin, L. P. & Liu, C. B. evolution in both vegetative and reproductive Department of Agricultural Chemistry, National Taiwan characteristics have led to taxonomic confusion at the University, Taipei, Taiwan 106 Republic of China generic and tribal levels. In this study, morphological characters used for grouping genera and tribes are The mixotrophic growth process has been used for the examined and assessed in light of a molecular-based large-scale production of Chlorella, in Taiwan, for phylogeny inferred from sequence analysis of the almost 40 years. The total production of Chlorella chloroplast-encoded gene rbcL. So far, phylogenetic products, mainly spray-dry powders, in Taiwan, peaked analyses support the distinction of the two subfamilies. to 1,400 tons per year in 1992. Production for 1997 was Sarcomenia delesserioides, allied historically with both at the 1,000 tons per year level. Main pond the Rhodomelaceae and Delesseriaceae, is found to construction, as a scale-up from innoculum culturing cluster with the Dasyaceae. ponds, is most effectively done by using a proportional increase of pond area. This allows for a uniform 80 increase in culture volumes. Mixing in the main PHYLOGENETIC ANALYSIS OF rbcL culturing is done by energy saving double agitation SEQUENCE DATA FOR PACIFIC SPECIES OF systems. Suitable amounts of acetic acid, and nutrients PORPHYRA are added to the basal media according to Chlorella cell Lindstrom, S.1, Candia, A.2, Nelson, W.3, & Fredericq, growth stage. Specific considerations are the precautions S.4 taken to eliminate bacterial contaminants, mainly 1Department of Botany, University of British Columbia, photosynthetic bacteria, by treatment through rotary Vancouver Canada; 2Facultad de Ciencias Naturales y moving Nylon-sheet filters, especially for an innoculum Oceanograficas, Universidad de Concepcion, preparation. A standard practice is to treat the harvested Concepcion, Chile; 3Museum of New Zealand Te Papa cells with special steaming devices to destroy Tongarewa, Wellington, New Zealand; 4Department of contaminated bacteria and stop chlorophyllase activities. Biology, University of Southwestern Louisiana, The growing conditions in Taiwan easily allow for a Lafayette, LA 70504 USA growth rate 10 g m-2 day-1 to be reached. Theoretically, under present day situation more than 2.0 L glacial acids The rbcL gene was sequenced in more than 20 species are required to produce 1 kg Chlorella spray-dried of Porphyra from Pacific waters (Alaska, British ABSTRACTS 31

Columbia, Chile and New Zealand). Relationships among the species were examined using PAUP The euglenoids are an ancient and extremely diverse (Phylogenetic Analysis Using Parsimony). Sequence lineage of eukaryotic flagellates with unclear intra- and data upheld some previously recognized relationships, inter-taxon relationships. Euglenoids are joined by such as Porphyra abbottae and Porphyra torta being unique symplesiomorphies, such as a surface pellicle each other's closest relatives, but they also produced and a closed mitosis with a series of separate sub- some surprising groupings. Collapse of the single most spindles. The taxonomy currently in use for the parsimonious tree after bootstrapping into two major euglenoids is inconsistent with the available data and is polytomies suggests at least two major radiations have in need of modification and revision. Most euglenoid occurrred within this group of species. The deeper phylogenies are largely intuitive reconstructions which polytomy includes the three distromatic species sampled are based on a limited number of morphological (Porphyra cuneiformis, Porphyra papenfussii and characters. Therefore, we have chosen to add molecular Porphyra schizophylla). The present analysis supports characters from the SSU rDNA to the morphological the position of Bangia as the sister taxon to a data to generate an overall phylogenetic framework for holophyletic Porphyra. the euglenoids from which a taxonomy can be established. SSU rDNA sequences from photosynthetic, 81 osmotrophic and phagotrophic euglenoids were aligned INDUCTION OF CONCHOSPORE RELEASE: based on secondary structure, using the model of VARIATIONS ON A THEME IN NORTHEAST Euglena gracilis (Van de Peer, et al. 1997) as a guide. PACIFIC SPECIES OF PORPHYRA Phylogenetic analysis on the conserved areas of the Lindstrom, S., Conitz, J., Hall, S., & Stekoll, M. sequence was performed using the programs PAUP* University of Alaska Southeast at Juneau & School of 4.0d (Swofford, 1991) and TREECON 1.3b (Van de Fisheries and Ocean Sciences, Juneau Center, Peer, Y. and De Wachter, R. 1997). Trees derived University of Alaska at Fairbanks), Juneau, AK 99801 using different criteria are in agreement. The USA euglenoids form a distinct monophyletic clade with phagotrophic members diverging prior to the Interest in Porphyra mariculture in Alaska and a phototrophic and osmotrophic members. Also, among proscription against importing non-indigenous species or the photosynthetic members, the biflagellate form stock prompted us to investigate conditions that diverged prior to the uniflagellate form. Additionally, stimulate release of conchospores in local species of the genus Euglena appears to be paraphyletic with interest. Many of these species had been investigated osmotrophic taxa such as Astasia and Khawkinea falling earlier by Waaland and colleagues using strains from out within the photosynthetic Euglena clade. Washington state. We observed at least one signficiant difference in release conditions in Alaskan strains of 83 Porphyra abbottae, Porphyra fallax and Porphyra torta MICROPHOTOMETRIC ASSESSMENT OF compared to Washington strains. We have also SPECTRAL ABSORPTION AND ITS POTENTIAL produced blades from conchocelis of Porphyra APPLICATION FOR CHARACTERIZATION OF cuneiformis and Porphyra pseudolinearis, although the HARMFUL ALGAL SPECIES latter less reliably than we would like. Monosporangia Lohrenz, S.1, Fahnenstiel, G.,2 & Kirkpatrick, G.3 were observed on the conchocelis of most of these 1University of Southern Mississippi, Department of species under certain conditions. Our results confirm Marine Science, Stennis Space Center, MS 39529 USA; that species of Porphyra in this region have fairly 2National Oceanic & Atmospheric Administration, Great specific requirements for release of conchospores and Lakes Environmental Research Laboratory, Muskegon, that important differences in these conditions can arise MI 49441 USA; 3Mote Marine Laboratory, 1600 between populations within a region, perhaps eventually Thompson Parkway, Sarasota, FL 34236 USA leading to speciation. Spectral absorption properties of phytoplankton have been used for both taxonomic and photo-physiological 82 characterization and in support of bio-optical algorithms PHYLOGENETIC ANALYSIS OF EUGLENOIDS for estimating pigment concentrations and primary USING 18S SSU RDNA. production. Conventional methods for the assessment Linton, E. W., Lewandowski, C. & Triemer , R. E. of spectral absorption (measurements in suspensions or Department of Cell Biology and Neuroscience, Rutgers on samples concentrated on filter pads) can be used only University, Piscataway, NJ 08854 USA. to characterize bulk properties of natural populations, 32 ABSTRACTS thus making it difficult to identify contributions by suggests that, if the isolates in our study represent the individual species or taxa. Microphotometric methods same phase, then the doubling sequence in nuclear DNA allow the determination of spectral absorption properties content could be the result of the variation in of individual cells. As a compliment to existing cell- chromosome numbers, thus indicating that evolution in specific measurements (e.g., autoradiography, flow this group has involved polyploidy accompanied by cytometry, etc.), this method enhances capabilities for doubling of genome size. probing the photo-physiology, growth and productivity of distinct taxonomic groups. Methods for 85 microphotometric assessment of individual particle CONTINUOUS MITOCHONDRIAL LARGE absorption spectra are described and compared to other SUBUNIT RIBOSOMAL RNAs IN CEPHALEUROS techniques. Results with a variety of laboratory PARASITICUS KARSTEN (TRENTEPOHLIALES, cultures, including the toxic dinoflagellate, CHLOROPHYTA): PHYLOGENETIC Gymnodinium breve, will be presented. Factors IMPLICATIONS influencing variability in spectral absorption, including LÙpez-Bautista, J. M.1, Nedelcu, A. M.2, & Chapman, pigment composition and 'package effects', are R. L.1 evaluated both within and among algal taxa. Potential 1Department of Biological Sciences, Louisiana State applications of this technique forautoecological studies University, Baton Rouge, LA 70803 USA; 2Department of harmful algal species in mixed populations will be of Biology, Dalhousie University, Halifax, NS B3H4J1 discussed. Canada

84 Both continuous and discontinuous mitochondrial large KARYOLOGY AND NUCLEAR GENOME subunit ribosomal RNAs (mtLSU rRNA) have been QUANTIFICATION IN THE ORDER reported among green algae. The phylogenetic TRENTEPOHLIALES (CHLOROPHYTA) distribution of these two types of mtLSU rRNA has LÙpez-Bautista, J. M.1, Kapraun, D. F.2, & Chapman, been shown to be consistent with phylogenetic R. L.1 relationships previously suggested by both 1Department of Biological Sciences, Louisiana State ultrastructural and nuclear rRNA sequences. University, Baton Rouge, LA 70803 USA; 2Department Discontinuous mtLSU RNAs have only been found in of Biology, University of North Carolina at Wilmington, zoosporic chlorophycean lineages with a clockwise NC 28403 USA flagellar apparatus configuration as well as their autosporic relatives, whereas continuous counterparts Microspectrophotometry with the DNA-localizing have been reported in all the investigated zoosporic fluorochrome DAPI was used to quantify nuclear DNA green algae with a counterclockwise orientation as well content in eight species representing three genera of the as their autosporic descendents. Therefore, the type of green algal order Trentepohliales (Chlorophyta). mt rRNA can be used as an additional phylogenetic Comparisons of mean fluorescence intensity (If ) values character in resolving conflicting inferences of of algal nuclear genomes to those of chicken relationships among green algal lineages. erythrocytes (RBC) resulted in an estimate of 1.1 to 4.1 Trentepohliales provides an example. Its phylogenetic pg for the algae. The diplobiontic life cycle of the position raises questions: on the basis of the Trentepholiales is not well documented, and it could not counterclockwise flagellar apparatus as well as on the be determined if our non-reproductive samples were phylogenetic analysis of nuclear-encoded rRNA gene sporophyte or gametophyte, and thus no ploidy level sequences, this group is assigned to the (or was assigned. However, our genome quantification data to a phylogenetic position close to the Ulvophyceae), but show a clear doubling sequence in nuclear DNA phragmoplast type cell division in these algae is a major content. This feature can be explained in one of two charophycean character. Our studies indicate the ways: the simplest explanation is that these isolates presence of continuous mtLSU rRNAs in Cephaleuros represent a mixture of generations, with both haploid parasiticus, a result that is consistent with an gametophytes and diploid sporophytes. A more ulvophycean affinity. More information on additional interesting hypothesis involves karyotype data: available Trentepohliales as well as ulvophycean taxa is needed in data (recorded for 15 taxa) show a large scale variation order to confirm our suggestions. in chromosome numbers (from [4]12 to 56) in the Trentepohliales. This range of chromosome numbers 86 could represent a polyploid series. Our hypothesis ABSTRACTS 33

PLASMID-LIKE DNA MOLECULES IN physiological state of cultures, as well as on the ability COENOCYTIC GREEN ALGAE ARE of species store nitrogen pools. Techniques for CHLOROPLASTIC IN LOCATION AND IN extracting intracellular inorganic nitrogen (IIN) show ORIGIN different degrees of efficiency, as a result of the kind of Loudenslager, C., Wang, J. & La Claire II, J. W. sample and the biochemical composition of the species. Department of Botany, University of Texas at Austin, A new methodology for extracting IIN was tested with Austin, TX 78713 USA samples from different growth phases of Dunaliella tertiolecta, Chlorella minutissima, Tetraselmis gracilis, Plasmid-like molecules have been isolated from Isochrysis galbana, Nannochloropsis oculata, Hillea Ernodesmis verticillata and Ventricaria ventricosa. sp., Skeletonema costatum, Phaeodactylum tricornutum, Molecular cloning of restriction fragments of these Synechococcus subsalsus and Prorocentrum minimum. molecules has provided probes for analyzing these Samples of cultures (40 - 120 mL) must be filtered unusual molecules further. Fluorescence in situ through fiberglass filters previously treated in muffle hybridization demonstrates that the plasmids are furnace at 400 C for four hours. The method includes exclusively located within chloroplasts. This finding immersion of samples in 30 mL of Milli-Q water would explain how plasmids are transmitted from the (MQW) for 12 hours at 4 oC. After this period samples multinucleate phases to the uninucleate flagellated stages are immersed in 15 mL of hot MQW (70-80 C) for two and back again. Whereas the chloroplast genomic DNA minutes, followed by flux of small amounts of MQW exists as nucleoids scattered throughout each plastid, the through the samples/filters, provided by a vacuum plasmids are arranged in a spherical configuration pump. All volumes of water are gathered, filled to 100 around the pyrenoid. The only homologies revealed mL and the IIN is measured by conventional from plasmid sequence analyses are short stretches of methodologies for analysis of dissolved inorganic deduced amino acid sequences with high degrees of nutrients. The combination of three different treatments identity to protein components of photosystems I and II. (osmotic shock, heating and flux of water through Thus far, these include portions of psbA, psbB, psbC, samples) seems to increase IIN extraction. Present psbF and psaB genes. The clone containing the psbB results are at least 20% greater than the IIN values gene fragment also labels a discrete band in northern available in the literature, indicating high efficiency of blots that corresponds in size to a band labeled with a the new technique. psbB gene probe from Chlamydomonas. Surprisingly, neither the homologous nor heterologous probes label 88 chloroplast genomic DNA in Southern blots, instead SEASONAL FLUCTUATIONS IN TISSUE hybridizing solely to plasmid DNA. These data NITROGEN AND PHOSPHORUS OF collectively suggest that green algal plasmids probably MACROALGAE FROM ARARUAMA originated from chloroplast DNA. However, their HYPERHALINE LAGOON, BRAZIL genes for photosynthetic proteins have apparently Lourenco, S.O.1, Barbarino, E.1, Nascimento, A.1, diverged sufficiently to preclude their hybridization to Paranhos, R.2, Gomes-Filho, J.C.F.3 & Yoneshigue- genomic DNA. These findings raise interesting Valentin, Y.1 questions about the gene content and organization of 1Department of Botany, 2Department of Marine Biology, chloroplast genomic DNA in these algae. Also it is Institute of Biology, Federal University of Rio de presently unclear whether functional psa/b transcripts Janeiro, Rio de Janeiro, RJ, Brazil; 3University of Rio arise from chloroplast genomic DNA, plasmid DNA or de Janeiro State, Rio de Janeiro, RJ, Brazil. both. Araruama Lagoon is a coastal environment in 87 Southeastern Brazil, under a subtropical climate. Former A NEW TECHNIQUE FOR THE EXTRACTION studies demonstrated that local macroflora is composed OF INTRACELLULAR INORGANIC NITROGEN by ninety-eight infrageneric algal taxa. N and P OF MARINE MICROALGAE contents of five abundant species (one Chlorophyta and Lourenco, S.O. & Barbarino, E. four Rhodophtyta) were analyzed during an annual Department of Botany, Institute of Biology, Federal cycle. Except for Gracilariopsis tenuifrons, all species University of Rio de Janeiro, Rio de Janeiro, RJ Brazil. presented great variations in the N, P, and N:P (by atoms) values along time. Among the five species the N The quantification of intracellular nitrate, nitrite and concentrations varied from 1.9% (Ulva lactuca, Spring) ammonium may provide important information on the to 8.3% (Acantophora spicifera, Winter) of dry weight. 34 ABSTRACTS

P contents ranged from 0.24 % (G. tenuifrons, Winter) 1Graduate School of Oceanography, University of Rhode to 0.71% (Hypnea cornuta, Fall) of dry weight. Island, Narragansett, RI 02881 USA; 2Department of Results for N:P ratio indicated high values, ranging Biomedical Sciences, University of Rhode Island, from 13.2 (U. lactuca, Spring) to 29.4 (Gracilaria Kingston, RI 02881 USA cervicornis, Fall). The analysis of dissolved inorganic nutrients in the water showed low P concentrations, A large-scale culture system for marine microalgae was agreeing with predominance of high N:P ratios obtained developed to reliably provide pharmaceutically for species. Although Araruama Lagoon shows promising metabolites in the quantity needed for characteristics of an eutrophic environment, increments chemical analyses, pharmacological evaluations and of macroalgal biomass seem to be limited by phosphorus clinical testings. The outdoor system was built upon availability. existing 15000-liter cylindrical tanks using enriched filtered coastal seawater. The enclosed cultures were 89 gently stirred and aerated; solar radiation was FOOD UPTAKE IN MIXOTROPHIC supplemented with overhead lamps and an underwater DINOFLAGELLATES USING MEMBRANE very high output fluorescent unit. Temperature was o MARKERS maintained within 2 C of the target with a submerged Maranda, L. heating/cooling unit. Three clones were grown: Graduate School of Oceanography, University of Rhode Amphidinium operculatum var. gibbosum, a free- Island, Narragansett, RI 02882 USA swimming dinoflagellate producing metabolites with antitumor activity; Prorocentrum mexicanum, a thecate Evidence of widespread mixotrophy in dinoflagellates benthic dinoflagellate; and Pseudo-nitzschia multiseries, has been accumulating in recent years, with few data on a boreal-temperate pennate diatom producing domoic the relative contribution of phototrophy and acid. Cells in early stationary phase of growth were heterotrophy to the growth of the photosynthetic precipitated, the supernatant was siphoned off and the predator. An approach was sought that would allow slurried precipitate was harvested by continuous detection and quantification of the feeding process centrifugation. Amphidinium operculatum var. especially in marine protists bearing chloroplasts, not gibbosum reached concentrations over 10 millions cells only under controlled culture conditions but in field per liter, with a growth rate of 0.35 per day; however populations as well. A membrane marker technique production of metabolites was low and cell leakage used to study endocytosis in motor nerve terminals and during harvest could not be excluded. Several attempts in fertilized has been applied to the study of with P. mexicanum and P. multiseries failed, mostly as phagocytosis in mixotrophic protists. Although the a result of light limitation, pH fluctuations and the protocol is still in development, experiments with presence of contaminants passing through the filtration bacterized cultures of Gymnodinium sanguineum and system. Culturing success appeared to heavily depend Prorocentrum micans exposed to fluorescent styryl dyes on the level of solar radiation received by the culture in have demonstrated that the probes are non-fluorescent the first 10 days, a condition which may jeopardize the when dissolved in seawater but fluoresce as soon as they use of the facility during the winter months at our attach to membranes, are completely non toxic for latitude, unless additional artificial lighting is provided. several days and become associated with cellular inclusions. Work is in progress to confirm the nature of 91 the inclusions as food vacuoles. Because visual THE BIOALGICIDAL POTENTIAL OF FRESH discrimination between photosynthetic pigments and CUT ALFALFA AND REED CANARY GRASS ON probes is easily accomplished by epifluorescence SEVERAL ALGAL SPECIES microscopy, the technique appears promising in Marencik, J. & Lembi, C. quantifying the fluorescent inclusions using image Department of Botany & Plant Pathology, Purdue analysis software. University, West Lafayette, IN 47907 USA

90 The bioalgicidal properties of several forages and straws LARGE SCALE CULTURE OF MARINE were examined as an alternative to the use of copper PHOTOSYNTHETIC MICROALGAE FOR containing algicides. The algicidal effects of barley BIOMEDICINAL PRODUCTION straw have previously been documented. However, the Maranda, L.1, Zhang, J.1, Zheng, N.2, Klos, E.1, availability of barley straw can be a problem. In Hargraves, P. E.1 & Shimizu, Y.2 response to this problem, an algal screen was developed ABSTRACTS 35 to test other forages and straws that might also be amplification of genomic DNA with arbitrary primers effective bioalgicides. Nine different forages and straws (Random Amplified Polymorphic DNA´s, RAPD´s) were tested on twelve algal species. The forages and allowed to find one RAPD marker for male individuals straws that were assayed included barley, fescue, reed of Gracilaria gracilis. The marker was linked to the canary grass, alfalfa haylage, fresh cut alfalfa, rye, male allele and, as expected, it was also present in birdsfoot trefoil, wheat, and oats. The algal screen diploid tetrasporophytes. The marker presence was included Anabaena, Ankistrodesmus, Euglena, tested on 59 gametophytic individuals (39 males and 20 Gloeocapsa, Navicula, Oscillatoria, Pithophora, ) germinated, in situ, from spores of a single Scenedesmus, Selenastrum, Spirogyra, Synechococcus, tetrasporophyte. This segregation analysis showed and Synedra. The forages and straws, at a rate of 5g dry almost 100% linkage of the RAPD marker to the male material L-1, were decomposed in barrels filled with allele. water. The liquids from the decomposed plant material were then tested at monthly intervals for algicidal 93 properties. Fresh cut alfalfa and reed canary grass EXTINCTION AND rbcl RATE showed the most promising results. Growth rates were HETEROGENEITY AMONG MAJOR LINEAGES significantly reduced for several of the target groups OF THE CHARACEAE (CHAROPHYCEAE) such as cyanobacteria and filamentous algae. McCourt, R. M.1, Karol, K. G. 1, & Feist, M.2 Reductions of greater or equal to 50% of the control 1Academy of Natural Sciences, Philadelphia, PA 19103 will be reported. USA; Laboratory of Molecular Systematics, Smithsonian Museum Support Center, Suitland, MD USA; 2Laboratoire de Paleobotanique, Universite Montpellier 2, Place Eugene BataillonF-34095, Montpellier, France

92 Charophytes are nonmarine green algae that are close A MOLECULAR MARKER HIGHLY LINKED TO relatives of land plants according to recent molecular THE GENE IN GRACILARIA GRACILIS and morphological studies. The oldest fossil Martínez, E. A. 1, Valero, M.2 & Destombe, C.2 fructifications (termed gyrogonites) of these algae are 1Deparamento de Ecología, Pont. Universiad Católica found in later Silurian-Early Devonian, after which the de Chile, Casilla 114-D, Santiago, Chile; 2Laboratoire group experienced several phases of diversification and de Genetique et Evolution des Populations Vegetales, extinction. A distinct break occurred at the Cretaceous- URA CNRS 1185, Bat. SN2, Universite de Lille I, Tertiary Boundary in charophyte diversity: this event Villeneuve d'Ascq, 59655, France. was marked by the extinction of about fifty per cent of the taxa. The major difference between the Cretaceous Among red algae, sexual reproduction is widespread and and Tertiary charophyte floras is the disappearance of its morphological and cytological bases have been well the Clavatoraceae family, which became extinct at the described (Hommersand and Fredericq 1990, for same time as the last dinosaurs at the end of the review). However, on a genetic level, there is still a Cretaceous (Dinosaur have been found great lack of information concerning sexual together with gyrogonites in several localities of the determination. For Anthithamnion spirographidis, terminal Cretaceous). However the extinction crisis Drew (1955) indicated that segregation of sex occurred during a diversification phase of one family, chromosomes during meiosis explains the equal numbers the Characeae, which is the only surviving family of of male and gametophytes. More recently, van charophytes. Molecular studies of the chloroplast- de Meer (1990) suggested that the primary control of encoded Rubisco large subunit (rbcL) gene show large sex determination in Gracilaria thikvahiae is given by a differences in sequence divergence within the six extant single pair of alleles designated mtf (female mating type) genera, in particular between lineages containing the and mtm (male mating type) rather than by sex two most species-rich genera, Chara and Nitella. We chromosomes as it happens in some brown algae (Evans hypothesize either or both of the following processes 1965, Yabu and Sambonsuga 1981). In this study, in may be responsible: (1) rates of rbcL evolution varied order to search for a molecular marker linked to sex between genera, (2) extant species in the two groups genes we used a modified version of Bulked Segregating represent diversifications from ancestors of very Analysis, a tool normally applied to find molecular different ages. markers for disease resistance or susceptibility in plants of agricultural interest. This method, based on the 94 36 ABSTRACTS

MOLECULAR BIOLOGY OF ACYL CARRIER PROTEIN IN CHAETOCEROS MUELLERI AND Methods for producing protoplasts from red algal spores NITZSCHIA ALBA were recently developed. Spore-protoplasts are McGinnis, K., Bingham, S., & Sommerfeld, M. totipotent and exhibit increased viability and Department of Plant Biology, Arizona State University, regeneration. Spore-protoplats made from tetraspores Tempe, AZ 85287 USA were cultured to produce callus-like masses of filaments which were isolated, repeatedly subcultured and used in Potential uses for triacylglycerols, storage products of mutagenesis experiments to produce Chondrus plants diatoms, have made biosynthesis of these molecules a with increased thermal tolerance. To date, UV-treated subject of increasing medical, industrial, and regenerants from filament cultures, followed by repeated commercial interest. The ubiquitous acyl carrier selection, have survived 56 days at 28 oC (42 days protein, an essential protein in fatty acid biosynthesis, is longer than previously reported) versus 14 days for highly conserved and a useful marker to study the controls. Spore-protoplasts from both life-history molecular biology of lipid biosynthesis. Using Southern phases of Chondrus crispus were utilized in fusion Blot Analysis, it was determined that two acyl carrier experiments to produce somatic hybrids. Successful protein genes are present in the chloroplast genome in fusions (44 plants) were microscopically identified, Chaetoceros muelleri, possibly within the inverted marked and transferred to bubbling flasks. Putative repeat characteristically present in diatom chloroplast fusion products were initially analyzed using micro- genomes. In diatoms, several fatty acid biosynthetic infrared spectrophotometry. One plant (7/12#1), genes are typically located in the chloroplast genome. produced in a haploid+diploid fusion experiment, had a However, little is known about lipid biosynthesis and spectrum similar to a gametophyte, except that the 805 the chloroplast genome of non-photosynthetic diatoms, cm-1 peak, indicative of 3,6 anhydrogalactose-2-sulfate, such as N. alba. Fluorescent microscopy using DAPI was absent. Carrageenan analysis of 7/12#1 revealed a stain indicates that a plastid genome is maintained in N. molar ratio of 1:0.5: 0.92 (galactose: 3,6 alba. However, total genomic DNA extraction and anhydrogalactose: sulfate), unlike a typical Chondrus separation on a cesium chloride gradient yields gametophyte of 1: 0.8: 1.27. In addition, the DNA level predominantly nuclear DNA, suggesting that the plastid of 7/12#1, as revealed by DAPI genome is greatly reduced. This suggests that the gene microspectrofluorometry, was 0.36 pg while for acyl carrier protein and other fatty acid biosynthetic gametophyte and tetrasporophyte controls were 0.23 and proteins may be encoded in the nucleus of N. alba. 0.47pg, respectively. This is the first report of Southern Blot Analysis is being used to determine aneuploid production and cell wall constituent alteration whether acyl carrier protein is nuclear or plastid in a morphologically complex and commercially encoded in N. alba. Preliminary ultrastructure results valuable seaweed and gives validity to the use of spore- also indicate that N. alba has not retained typical protoplasts for fusion. chloroplast ultrastructure. Since fatty acid biosynthesis generally occurs in the chloroplast, immunoelectron 96 microscopy is being utilized to compare subcellular PHYLOGENY OF THE GREEN ALGAE: THE 28S localization of acyl carrier protein in Chaetoceros and RRNA GENE AND THE Nitzschia. Michalopulos, J. A. & Buchheim, M. A. Department of Biological Science, The University of 95 Tulsa, Tulsa, OK 74104 USA GENETIC MODIFICATION IN CHONDRUS CRISPUS THROUGH PROTOPLAST FUSION The green algal class has undergone AND MUTAGENESIS numerous, recent taxonomic revisions. However, Metz, B. R.1, Cheney, D. P.1, Chopin, T.2 & Kapraun, relationships between and within certain orders remain D. F.3 an open question. In particular, questions regarding the 1Marine Science Center, Northeastern University, Sphaeropleales have not been resolved. Utilizing partial Nahant, MA 01908 USA; 2Centre for Coastal Studies & sequences (ca. 2200 bases/taxon) from the 28S gene of Aquaculture, Department of Biology, University of New the nuclear-encoded rDNA gene array, the main Brunswick, Saint John, NB E2L4L5 Canada; objectives of this research were to test the monophyly of 3Department of Biological Sciences, University of North the genera within the family (sensu Carolina at Wilmington, Wilmington, NC 28404-3297 Mattox and Stewart), to examine relationships of taxa USA within the family, and to assess the position of the order ABSTRACTS 37

Sphaeropleales within the green algae. Analyses of the However, the diversity within the genus 28S data corroborated previous studies of the internal Chlamydomonas is consistent with higher level transcribed spacer (ITS) in rejecting monophyly of classifications of the green algae which implicitly soleirolii, a taxon united by shared zygote support the notion that heterogamy has evolved wall morphology but exhibiting diversity in vegetative independently in distinct families and orders. characters. The 28S data also were used to address questions regarding the enigmatic Sphaeroplea fragilis, 98 which does not possess an apical cone in the distal fiber STABILITY OF PSEUDO-NITZSCHIA (BACIL- of the male gametes. The 28S data support ITS and LARIOPHYCEAE) SAMPLES IDENTIFIED ultrastructural data in placing S. fragilis as a basal USING SPECIES-SPECIFIC FLUORESCENT IN member of the filamentous genus Sphaeroplea. Parallel SITU HYBRIDIZATION data sets, from the 18S and 28S rRNA genes, Miller, P. E. & Scholin, C. comprising a sampling of organisms representative of Monterey Bay Aquarium Research Institute, Moss the chlorophycean orders (sensu Mattox and Stewart) Landing, CA 95039 USA were compared. Both molecular data sets support a close alliance among Sphaeroplea, and Some species within the genus Pseudo-nitzschia are . Although Cylindrocapsa has been allied with associated with production of domoic acid, the agent Sphaeroplea in one classification (Sphaeropleaceae responsible for amnesic shellfish poisoning (ASP). sensu Mattox and Stewart), neither molecular data set Identification and enumeration of particular Pseudo- supports Cylindrocapsa as a close ally of the group. nitzschia, especially in natural populations that frequently harbor multiple species, is difficult and time 97 consuming because of a need for detailed morphological PATTERNS IN THE EVOLUTION OF observations that often require scanning electron SEXUALITY: THE CHLAMYDOMONAS microscopy (SEM). We have developed species- EXAMPLE specific large sub-unit ribosomal RNA (LSU rRNA)- Michalopulos, J. U. & Buchheim, M. A. targeted fluorescent DNA probes for a variety of Department of Biological Science, The University of Pseudo-nitzschia species. Probes are applied using Tulsa, Tulsa, OK 74104 USA whole cell hybridization and a custom filtration manifold, enabling rapid quantification of target species Chlamydomonas is a unicellular member of the green in field samples. A limitation of this method has been algal class Chlorophyceae. Although more than 400 the perceived necessity for immediate sample species of Chlamydomonas have been described, the processing, restricting the practicality of analyzing a sexuality of only a few is known in detail. Of these large number of samples for target species. In this species with known life histories, considerable diversity presentation we describe results of comparing a variety in the form of sexuality has been described. While most of fixatives and assessments of sample stability. Of the are isogamous, a few species exhibit heterogamy variety of fixes tested an ethanol-based treatment gave (including and oogamy). In addition, sexual the best results in terms of brightness and uniformity of species can be characterized as heterothallic or probe fluorescence. Culture samples treated with this homothallic. Heterogamy and homothallism are fixative and stored at either room temperature or –20 °C traditionally regarded as derived conditions. These were stable for at least three weeks, showing little signal assumptions about the polarity of sexual characters were degradation. Likewise a field sample stored in the same tested by phylogenetic analysis of DNA sequence data fixative at –20 °C was also stable for at least three from the 18S rRNA gene. Genomic DNA from sexual weeks. Post hybridization, samples stored at 4 °C were isolates of Chlamydomonas served as templates for PCR found to retain their fluorescence for approximately amplification of the 18S rRNA gene. Amplified product three weeks. These results indicate there is a wider was sequenced by automated methods. The sequence window of opportunity for analyzing samples than we data were aligned and analyzed using computer-based previously thought, allowing the accumulation of phylogenetic methods. Results from phylogenetic potentially interesting samples for later analysis. analysis suggest that heterogamy and homothallism have 99 evolved independently in several lineages. Within the IMPACT OF A RECCURENT COASTAL PLUME Chlamydomonadales, homothallism appears to be the ON LAKE MICHIGAN PHYTOPLANKTON; A ancestral condition. These observations challenge PRELIMINARY ASSESSMENT traditional concepts of sexual character stability. 38 ABSTRACTS

Millie, D.1, Fahnenstiel, G.2, Schofield, O.3, & Lohrenz, S.4 The response to UV-B radiation was evaluated in two 1U.S.D.A., Agricultural Research Service, New distinctly different phytoplankton species of the Pacific Orleans, LA 70124 USA, 2 N.O.A.A., Great Lakes coast of South America. Various physiological Environmental Research Laboratory, Muskegon, MI parameters (specific growth rate, photoreactivation, UV- 49441 USA; 3Rutgers University, Institute of Marine & absorbing compounds, photochemical capacity, Coastal Sciences, New Brunswick, NJ 08901 USA; photosynthesis vs. irradiance, soluble proteins and 4University of Southern Mississippi, Department of Rubisco) were compared in order to assess whether the Marine Science, Stennis Space Center, MS 39529 USA two species differ in their photoadaptational responses to UV radiation. A Magallanes isolate of the red tide A recurrent coastal plume (RCP) of resuspended dinoflagellate, Alexandrium catenella, and a central materials occurs annually within southern Lake coast isolate of the diatom, Phaeodactylum tricornutum, Michigan. This highly reflective, turbid plume appears were grown on a 16:8 photoperiod in polyethylene bags to be initiated by a major late winter storm immediately and f/2 medium. Exponential cultures, acclimated to after ‘ice out’. The silt- and clay-like particles 103 mmol m-2s-1 PAR and 4 Wm-2 UV-A radiation, were composing the RCP are thought to originate on the exposed for 2 or 4 h daily to 0.11 to 1.31 Wm-2 UV-B lake’s western shore before transport to the resuspension radiation provided by fluorescent UVB-313 lamps. site. The RCP may extend greater than 10 km in width Cultures were covered by optical filters to eliminate and 300 km in length and eventually veers offshore UV-B and/or shorter wavelengths. UV-A (365 ± 12 along the eastern shoreline, coinciding with the area of nm) and UV-B (313 ± 12 nm) radiation were measured highest measured sediment accumulation in the lake. In with an interference filter radiometer. Although A. this introductory year of a 5 year, NSF-NOAA catenella synthesized considerable amounts of UV- interdisciplinary program assessing this episodic event, absorbing compounds, whereas P. tricornutum did not, we are evaluating the impact of the RCP on the lake’s the dinoflagellate was far more sensitive to UV-B phytoplankton assemblages. Although both light and radiation than the diatom: a 50% reduction in growth nutrient availability appear to regulate assemblages was measured at 0.4 Wm-2 (2 h d-1) for A. catenella and during the spring isothermal period, linkages between at 1.13 Wm-2 (4 h d-1) for P. tricornutum. The higher the RCP and phytoplankton growth and primary resistance to UV-B radiation by P. tricornutum is production have been postulated, but not verified. As consistent with measurements of photoreactivation such, the RCP provides a novel opportunity to examine suggesting higher rates of DNA repair compared to A. the influence of light availability on phytoplankton rate catenella. While our results point to important processes at both the species and community-levels. differences in the photoadaptational responses to UV-B During a series of spring cruises incorporating both radiation of these two organisms, they do not provide process measurements and langrangian experiments, the clues to explain the persistence of A. catenella blooms physical, optical, and autotrophic components of the in high UV radiation environments. water column were characterized. Here, we summarize the impact of the RCP with respect to the light-limitation of natural populations. The impact is characterized using phytoplankton production, growth, light 101 absorption, quantum yield, and biomass measurements. COMPARATIVE MOLECULAR ANALYSES OF PORPHYRA PLASMIDS DEMONSTRATE INTE- GRATION INTO ORGANELLAR DNA OF SOME SPECIES Moon, D. & Goff, L. J. 100 Department of Biology, University of California at PHYSIOLOGICAL RESPONSE TO UV-B Santa Cruz, Santa Cruz, CA 95064 USA. RADIATION STRESS IN TWO MICROALGAE FROM THE COAST OF CHILE. Conspicuous plasmids are visible in electrophoresed Montecino, V.1, Hannach, G.1 , Molina, X.1, Martínez, genomic DNA of many , including some red G.1, Olmedo, M.1 and Orellana, M.2 algae, but these are apparently absent in the DNA of 1Fac. Ciencias, Universidad de Chile, Casilla 653, closely related species. The present study explains this Santiago, Chile; 2Department Bioengineering, paradox for some species in the genus Porphyra: University of Washington, Seattle, WA 98195 USA plasmid-homologous sequences can be cryptic because ABSTRACTS 39 they are integrated within organellar genomes. similar trends to those of the 18s rRNA gene analysis Porphyra pulchra plasmids Pp6859 or Pp6427 were for this genus. All freshwater collections were nearly used to screen Southern blots of other northeastern identical and group consistently together in the Pacific Porphyra species for homologous sequences. phylogenetic trees. Marine collections form several Pp6859 hybridized to high molecular weight DNA in P. well supported clades within Atlantic and Pacific basins. nereocystis and P. abbottae. Pp6427 hybridized to high The presence of introns within other bangiophyte taxa molecular weight DNA in Bangia sp. and P. lanceolata. will also be discussed. Molecular characterization of clones isolated from P. lanceolata document the insertion of plasmid- 103 homologous sequence (approximately 4300 base pairs) PRODUCTION AND CHEMICAL ECOLOGY OF into the chloroplast genome. Through comparison to CYANOBACTERIAL METABOLITES the published P. purpurea chloroplast genome (Genbank Nagle, D. G.1,2 & Paul, V. J.2 Accession #U38804) the site of insertion maps to the 1Department of Pharmacognosy and National Center for tRNA for isoleucine. Regions flanking the insertion are the Development of Natural Products, Research Institute clearly identifiable and conserved. Many organisms of Pharmaceutical Sciences, School of Pharmacy, The lack introns in chloroplast genes for isoleucine tRNA, University of Mississippi, University, MS, 38677, USA; including Spinacia oleracea, Picea abies, 2University of Guam Marine Laboratory, UOG Station, Chlamydomonas reinhardtii, and Euglena gracilis. Mangilao, GU, 96923. Other species contain introns in the isoleucine tRNA gene (Porphyra purpurea, Marchantia polymorpha, and Cyanobacteria are recognized as a rich source of toxins Zea mays) and their introns begin in a similar position, and other pharmacologically active compounds. Often but these are smaller (241 to 950 bp) and share no chemical studies have focused on toxin production. sequence similarity to the P. lanceolata plasmid-like However, cyanobacteria also appear to produce a wide insertion. Given that many Porphyra species maintain assortment of unusual secondary metabolites for which distinct high copy number plasmids, the presence of a little or no biological or biochemical role has been substantial plasmid fragment in the plastid genome of P. attributed. Ongoing research suggests that many of lanceolata may indicate trapping of a moveable these metabolites may be ecologically important. For sequence element. example, some of the metabolites produced by cyanobacteria appear to function as effective feeding 102 deterrents to both vertebrate and invertebrate grazers. A PRELIMINARY ANALYSIS OF THE GROUP I The production of cyanobacterial chemical defenses INTRONS IN THE 18S RRNA GENE OF BANGIA may, in some cases, actually facilitate the formation of (BANGIALES) RHODOPHYTA cyanobacterial blooms. This appears to be especially Mòller, K. M.1, Gutell, R. R.2 & Sheath, R. G. 1 true in the presence of grazers. In highly competitive 1Department of Botany & Dean's Office, College of environments, other metabolites may function to Biological Science, University of Guelph, Guelph, ON suppress bacterial and fungal overgrowth or act N1G2W1 Canada; 2Department of Chemistry & allelopathically to inhibit the growth of other Biochemistry, University of Colorado, Boulder, CO cyanobacteria and algae. 80309 USA 104 A large insertion was found near the 5' end (helix 21) of ASSIMILATORY NITRATE REDUCTASE FROM the 18S rRNA gene in a variety of global collections of THE RAPHIDOPHYCEAE HETEROSIGMA the genus Bangia. Subsequent sequence analysis of this AKASHIWO CONTAINS PROTOZOAN region displayed many characteristic sequences and HEMOGLOBIN. structural features similar to the C1 subgroup of group I Nakamura, Y.1 & Ikawa, T.2 introns. RT-PCR (reverse transcriptase PCR) revealed 1Department of Botany, Iowa State University, Ames, IA that this insertion is spliced out during transcription. In 50011 USA; 2Institute of Biological Sciences, University addition, a previously reported Group I intron near the of Tsukuba Japan 3' end of the gene was also present in some collections of Bangia. In fact, the samples displayed three different We isolated a cDNA encoding assimilatory nitrate configurations: those with both introns, those with only reductase (NR) of the marine Raphidophyte the intron near helix 21 or those with neither intron. from a library constructed in Phylogenetic analysis of the two introns has revealed lambda ZAP Express phage. Clones were screened 40 ABSTRACTS with a monoclonal antibody NR10 raised against NR 2000 mg L-1 ) of TBT were also assayed. Functional from the marine red alga Porphyra yezoensis, which has and structural alteration of mitochondria might be the the cross reactivity to molybdopterin . The 2.9 cause of the remarkable accumulation of paramylon in kb clone contained an open reading frame of 2,797 giants cells. Chloroplasts showed a severe nucleotides that hybridized to a 2.7 kb mRNA. The disorganization and swollen membranes. The Golgi deduced amino acid sequence contained 931 residues, bodies cisternae appeared dilate filled with conspicuous with a predicted molecular weight of 103,633. Amino secretion material. It may be concluded that the acid sequence comparison with other assimilatory NRs organometallic compounds would be more toxic than the has shown that NR from H. akashiwo, as well as typical inorganic salts, suggesting that they are more efficiently eukaryotic assimilatory NRs, includes three functional absorbed for its lipid solubility, and/or less excreted domains, each of which contains molybdopterin, heme, because of the strength of the cysteine (protein)-OT and FAD as prosthetic groups. However, the heme and bond. the FAD domains are separated by a polypeptide of 116 amino acids, which has 35 to 42% identity to 106 hemoglobins from the cyanobacterium Nostoc commune, NITRATE REDUCTASE ACTIVITY IN the green alga Chlamydomonas eugametos, the ciliated GRACILARIACEAE (GRACILARIALES, RHO- Paramecium caudatum, and Tetrahymena DOPHYTA). pyriformis. The protozoan hemoglobins comprise Oliveira, M. C.1, Chow, F. F.1, Rossa, M. M.1, Lopes, distinct group from the well-known hemoglobin and P. F.2 & Colepicolo, P.2 myoglobin family that includes leghemoglobin as well. 1Dept. Botanica, Inst. Biociencias, 2Dept. Bioquimica, This finding not only provides new insight into Inst., Quimica, University of Sao Paulo, Sao Paulo, evolution of eukaryotic NRs but also suggests the SP, Brazil. existence of various eukaryotic NRs differing in domain composition. Most of the agar produced today is obtained from Gracilariaceae cultivated in ponds or directly in the sea. 105 Therefore, there is a great interest in understanding the ULTRASTRUCTURAL CHANGES AND mechanisms of nutrition and growth of those algae. GROWTH RESPONSE OF EUGLENA GRACILIS Nitrogen is the major nutrient limiting macroalgal TREATED WITH INORGANIC AND ORGANIC production and its major source in the ocean is in the TIN COMPOUNDS form of nitrate, which must be reduced to integrate the Nudelman, M. A., Carro, C. & Conforti, V. nitrogen-containing biomolecules. Nitrate reductase Facultad de Ciencias Exactas y Naturales, Universidad (NR) is the crucial first enzyme in the nitrogen de Buenos Aires, 1428 Buenos Aires, Argentina reduction pathway and is the rate-controlling step which regulates the input of nitrogen into the organisms. In The toxicity of heavy metals have been studied in a this paper we compare some of the biochemical features variety of organisms, including algae but the effects of of the NR activity from three commercially cultivated organometallic compounds have received much less species, Gracilaria tenuistipitata, Gracilaria chilensis attention. Organotin (OT) compounds are extremely and Gracilariopsis tenuifrons. Some of the factors poisonous and have been widely used as active regulating NR activity, optimal pH (8.0) and circadian ingredients in antifouling paints, as PVC stabilizers, oscillation were found to be similar for the three industrial and agricultural biocides. Its extreme toxicity species, but other factors varied. For G. tenuifrons has resulted in adverse biological effects on non-target optimal temperature was 30 oC, optimal NADH organisms. In the present study, the effect of inorganic concentration was 0.01 mM, the activity plateau was tin (SnCl4) and organotin compounds (TeBT and TBT) reached after 60 min, and the enzyme was quite stable in on Euglena gracilis was evaluated. The toxicants were the crude extract when kept at 4 oC (90% of activity added in series ranging from 0 to 50 mg ml-1. Growth remains after 48 h). For G. chilensis optimal inhibition was observed in the OT-treated cultures, temperature was 20 oC, optimal NADH concentration being most severe the effect of TBT. Ultrastructural was 0.04 mM, the activity plateau was reached after 10 damage was analyzed by means of TEM. Recently, we min, and the enzyme was less stable in the crude extract had reported the lethal effect of 50 ugml-1 of TBT on E. when kept at 4 oC (17% of activity after 48 h). These gracilis: no organelles could be distinguished after 96 hs results are compared to previous results obtained for G. exposure. To determine the sequence of alterations tenuistipitata. prior to the cell death, sublethal concentrations (0 to ABSTRACTS 41

107 revealed the presence of at least six species of Pseudo- FEEDING INTERACTIONS BETWEEN NATIVE nitzschia (P. pungens (Grunow) Hasle, P. multiseries OHIO RIVER MUSSELS (BIVALVIA: (Hasle) Hasle, P. pseudodelicatissima (Hasle) Hasle, P. UNIONIDAE) AND ZEBRA MUSSELS delicatissima (P. T. Cleve) Heiden, P. subfraudulenta (DREISSENA POLYMORPHA). (Hasle) Hasle, and P. sp. cf. americana). Domoic acid Parker, B. C. 1, Patterson, M. A. 1, & Neves, R. J.2 was detected in net tow samples indicating active toxin 1Department of Biology, 2Department of Fisheries & production. Spring and fall blooms occurred at much Wildlife Sciences, Virginia Tech, Blacksburg, VA 24061 lower levels than in the previous seven years and USA. consisted of a mixture of species. Pseudo-nitzschia We evaluated effects of zebra mussel infestation on the multiseries dominated at the estuarine site during late feeding of native unionids in the Ohio River through gut winter, whereas P. pungens exhibited a summer content analysis. In 1996, mean algal cell numbers in dominance in shelf waters. In addition to differential guts of heavily infested and lightly infested Amblema interference contrast (DIC) and scanning electron plicata (5.7 x 105 versus 9.1 x 105, respectively) were microscopy (SEM), the whole cell hybridization not significantly different (p = 0.17). But, heavily technique, utilizing species-specific large-subunit infested A. plicata had lower (p < 0.01) mean ash-free ribosomal RNA-targeted oligonucleotide probes, was dry weight (AFDW) in guts (1.4 mg) than lightly field tested for its ability to aid in detection and infested ones (4.6 mg). Mean algal cell number and quantifying the four most common species occurring in AFDW from heavily infested Quadrula pustulosa (1.8 x Louisiana coastal waters (first four listed above). 104 and 0.6 mg AFDW) also were lower (p < 0.05) Probes successfully detected their presence, even at than that of lightly infested ones (3.9 x 105 and 1.8 mg levels as low as 0.1% of the total phytoplankton AFDW, respectively). In 1997, significant reductions population. Probe estimates of the concentrations of the (p < 0.05) in total algal cells and AFDW in guts also four species, however, differed from DIC/SEM results. occurred for heavily vs. lightly infested A. plicata and This discrepancy appears to stem from the presence of Q. pustulosa. The guts of all zebra mussels attached to unlabeled cells due to poor physiological state or species individual unionids from Ohio River Mile 397 contained variability. Alternatively, the difference could reflect 50% more (p < 0.05) cells (2.3 x 105 versus 9.4 x 104, inherent differences between the two counting methods, respectively) and AFDW (4.55 mg versus 0.92 mg) as the probes detect live planktonic cells, whereas than individual infested unionids. Algal taxa at the DIC/SEM count all cells: live, dead, and hidden in fecal sediment-water interface were essentially the same as pellets and consumers. Nevertheless, these results those in guts of all mussels, confirming significant diet demonstrate the promise of probes in shellfish overlap. Thus, algal and detrital food resources of monitoring programs. unionid guts are greatly reduced by feeding of zebra mussels. Reductions in unionid ingestion is likely a 109 primary mechanism for reduced glycogen levels FACTORS REGULATING ACCUMULATION OF previously reported for heavily-infested unionids. CRYPTOPHYCIN-1 IN THE CYANO- BACTERIUM NOSTOC SP. GSV 224 108 Patterson, G. M. L. & Bolis, C. M. PSEUDO-NITZSCHIA IN LOUISIANA COASTAL Department of Chemistry, University of Hawaii at WATERS: MOLECULAR PROBE FIELD TRIALS Manoa, Honolulu, HI 96822 USA Parsons, M. L.1, Scholin, C. A.2, Doucette, G. J.3, Fryxell, G. A.4, Dortch, Q.1, & Soniat, T. M.5 The cryptophycins are cytotoxic depsipeptides produced 1Louisiana Universities Marine Consortium, Chauvin, by cyanobacteria of the genus Nostoc. Extensive in vivo LA 70344 USA; 2Monterey Bay Aquarium Research studies on cryptophycin-1 and a broad range of natural, Institute, Moss Landing, CA 95039 USA; 3Marine synthetic and semi-synthetic analogs has demonstrated Biotoxins Program, NOAA/NOS, Charleston, SC 29412 potent antitumor activity against a wide range of murine USA; 4Department of Botany, University of Texas, and human solid tumors. One such analog is currently Austin, TX, 78713 USA; 5Department of Biological being evaluated in Phase I human clinical trials. To Sciences, Nicholls State University, Thibodaux, LA assess the potential for commercial production of 70310 USA cryptophycin-1 (the most abundant naturally occurring congener), we have initiated a program aimed at Weekly (estuarine) and monthly (shelf waters) identification of the biological and physicochemical examination of the phytoplankton population in 1997 factors that influence growth and cryptophycin 42 ABSTRACTS accumulation in axenic laboratory cultures. The effects about 9% of the annual leaf carbon production of the of concentration and chemical form of major and minor mangal. nutrients, including nitrogen, phosphorus, magnesium, calcium, and iron, have been established by determining 111 the cryptophycin-1 content of control and treated DIVERSITY OF COCCOID ALGAE ISOLATED cultures using a sensitive HPLC assay. Cryptophycin-1 FROM THE ARROWWOOD NATIONAL is produced by actively growing cultures and WILDLIFE REFUGE LAKES, NORTH DAKOTA, accumulates in both the cell mass and in the surrounding DURING WINTER growth medium. Unlike most cyanobacterial secondary Phillips, K. A. & Fawley, M. W. metabolites examined to date, the accumulation of Department of Botany, North Dakota State University, cryptophycin-1 in culture is profoundly dependent upon Fargo, ND 58105 USA incubation conditions, exhibiting relatively narrow pH and nutrient concentration optima that are not coincident Unicellular autosporic coccoid green algae with optimal conditions for biomass accumulation. (Chlorophyta) are ubiquitous in freshwater ecosystems. Little is known about the distribution and diversity of 110 these organisms, primarily because of their simple MODELING THE DAILY AND ANNUAL morphology and small size. In addition, other green- PRODUCTION OF EPIPHYTIC MACROALGAE colored coccoid algae, such as xanthophytes and GROWING ON MANGROVE ROOTS , may confound identification. In this Pena, E. J. & Zingmark, R. study, we examined the diversity of autosporic coccoid Marine Sciences Program & Biological Sciences algae in the shallow lakes of Arrowwood National Department, University of South Carolina, Columbia, Wildlife Refuge (ANWR) near Pingree, North Dakota. SC 29208 USA For 3 consecutive winters (1994 to 1997), phytoplankton samples were collected at 4 sites on 3 A production simulation model was developed to lakes in the ANWR and a collection of 90 isolates of quantify daily and annual primary production of two coccoid algae was developed. A hierarchal approach dominant species of epiphytic macroalgae, Bostrychia was used to examine the diversity of these isolates. The calliptera (Montagne) Montagne, and Caloglossa methods in this approach included HPLC analysis of leprieurii (Montagne) J. Agardh growing on mangrove photosynthetic pigments, taxon-specific PCR primers, roots in a tropical estuary, Pacific Coast of Colombia. and PCR-RFLP of the 18S rDNA. Thus far, six 18S The model used hourly measurements of solar radiation, rDNA genotypes of coccoid trebouxiophytes, 3 and irradiance below the mangrove canopy, as forcing genotypes of coccoid chlorophytes, and 1 genotype of functions. The model which was validated using hourly coccoid eustimatophyte have been detected from these measurements of photosynthesis and of monthly biomass isolates. These results suggest a higher level of production, showed good agreement between observed diversity of coccoid algae than has been reported in and predicted values (r2 = 0.72, p< 0.01, and r2 = regional floras. 0.86, p< 0.01 respectively). The sensitivity analysis revealed incident irradiance, and attenuation by the 112 overlying water as the main factors that generally MOLECULAR INSIGHTS INTO THE resulted in lower estimates in the daily production rates. EVOLUTIONARY HISTORY AND BIO- Algal production was significantly higher (p< 0.01) GEOGRAPHY OF HAWAIIAN SPECIES OF during dry season (February to June) than during the SARGASSUM rainy season (October-December). Significant Phillips, P., Smith, C. & Clifford Morden, C. differences in daily production were found to correlate Botany Department, University of Hawaii at Manoa, with the number of hours they are exposed, and the time Honolulu HI 96822 USA at which low tide occurred during the day (p< 0.01). Thus, if low tide ocurred at solar noon (high irradiance) The ecologically important Pan-Pacific genus Sargassum production rates were lower than when low tide was used to examine, for the first time, evolutionary occurred in early morning or late afternoon (low and speciation processes in Hawaiian marine plants. irradiance). This is consistent with the P-I curves where Sargassum makes an excellent candidate for this type of the algae demonstrated an adaptation to shade. The research; in the Pacific it has over 300 hundred species, annual net production of the two species of macroalgae offering an unparalleled opportunity for phylogenetic -2 -1 was estimated at 469 g C m yr , which is equivalent to and biogeographic reconstruction. Within the Hawaiian ABSTRACTS 43 archipelago the 5 endemic species of Sargassum are Estuary, NC is experiencing an increase in the wide-spread and well defined ecological dominants. frequency, areal coverage, and duration of nuisance Molecular sequencing of a rapidly evolving chloroplast algal blooms. Chemotaxonomic approaches were gene region (rbcL-IGS-rbcS) was used to examne coupled with mesocosm (55 liter) and cubitainer (4 liter) introduction and speciation events. Over 35 sequences bioassays to determine Neuse River phytoplankton representing all four subgenera and half the family community responses to nutrient (ammonium, nitrate, Sargassaceae were used to construct a phylogeny. At phosphate) additions and mixing. Experimental results the genus level, this modern treatment confirms much of suggest that phytoplankton productivity is N-limited. the traditional taxonomic treatment but is in sharp Mixed conditions promote diatom growth while contrast to traditional evolutionary concepts within the phytoflagellate abundance is enhanced under static (non- genus. In terms of evolutionary history, rbcLS spacer mixed) conditions. The community exhibited data suggest that at least two introductions have given differential responses depending on the N source (nitrate rise to Hawaiian Sargassum species. A Californian link vs. ammonium). Ammonium additions promoted higher is suggested for two of the species, representing the first cyanobacterial growth and biomass accumulation than empirically based indication of biogeographic affinities nitrate amended treatments. Increasing anthropogenic for Hawaiian macro-algae. Molecular data also suggest ammonium inputs through atmospheric deposition may that speciation is occurring within this genus in an east support potentially harmful cyanobacterial blooms in to west direction in support of the vortex biogeographic estuarine and coastal waters. model. These data refute J. Agardh's evolutionary concept within the genus, provide insight into the 114 evolutionary history and biogeography of Hawaiian MOLECULAR ANALYSIS OF BACTERIA marine algae and lay an important foundation for future IMPLICATED IN SYNTHESIS OF SAXITOXIN research. Plumley, F.G.1, Wei, Z.1, Toivanen1, T. B.1, Doucette, G. J.2 & Franca, S.3 113 1Institute of Marine Science, University of Alaska, CHEMOTAXONOMIC APPROACHES FOR Fairbanks, AK USA; 2National Ocean Science Service, ASSESSING ENVIRONMENTAL CONTROLS Charleston Laboratory, Charleston, SC USA; 3National AND BLOOM POTENTIALS OF NATURAL Institute of Health, Lisboa, Portugal PHYTOPLANKTON COMMUNITIES Pinckney, J. L., Paerl, H. W. & Harrington, M. B. It is becoming increasingly obvious that bacteria play a Institute of Marine Sciences, University of North role in the synthesis of certain phycotoxins. Several Carolina at Chapel Hill, Morehead City, NC 28557 bacterial strains isolated from cultures of toxigenic USA dinoflagellates have been shown to be capable of autonomous production of compounds that are thus far Phytoplankton communities are composed of diverse indistinguishable from saxitoxins. These bacteria microalgal species, each with unique physiological contain genes that direct the synthesis of saxitoxin-like requirements for optimal growth. Species composition compounds and these genes are potentially more is regulated by the synergy of environmental and tractable targets for isolation and manipulation than are ecological conditions. A process-based understanding the putatively homologous dinoflagellate genes. To of the factors responsible for noxious/harmful algal identify these genes, we have pursued a molecular blooms is necessary for developing predictive models genetic approach with six bacterial strains and found that and designing effective management strategies for each was resistant to most antibiotics routinely used for mitigating the negative impacts of persistent blooms. selection of transposon-derived mutants and that four Microalgal photosynthetic pigments (chlorophylls & strains had high nuclease activity that further hindered carotenoids) are useful biomarkers for quantifying the attempts to produce mutants. Nonetheless, a strain of relative abundance of algal groups (dinoflagellates, Pseudomonas stutzeri associated with a toxic cyanobacteria, diatoms, etc.) in mixed assemblages. Alexandrium lusitanicum could be mutagenized and Photopigment radiolabeling techniques can provide transconjugants selected on either Km or Gm if cells measurements of the carbon-specific growth rates of were grown in a freshwater (rather than sea water) algal groups. Algal growth rates are sensitive indicators medium. We subsequently selected mutants that were of physiological responses to alterations in sensitive to Gm in sea water and found that a Tn5 environmental conditions and provide a rapid means of element was inserted into a two-component histidine determining algal bloom potentials. The Neuse River kinase gene that is specifically responsive to 44 ABSTRACTS calcium/ammonium/magnesium. We have also selected PHYSIOLOGICAL EFFECTS OF NITRATE ARG mutants because saxitoxins are built from three LIMITATION ON THE TOXIC arginine moieties. Eight mutants have been found that DINOFLAGELLATE ALEXANDRIUM are unable to transport and/or utilize exogenous arginine TAMARENSE FROM CASCO BAY, MAINE supplied as the sole carbon/energy/nitrogen source. We Poulton, N. J.1, MacIntyre, J. G.2, Cullen, J. J.2 & have just begun to screen for mutants unable to Anderson, D. M.1 synthesize saxitoxin and hence, are expected to have Tn 1Woods Hole Oceanographic Institution, Woods Hole, elements inserted into the genes required for saxitoxin MA 02540, USA; 2Department of Oceanography, synthesis. Dalhousie University, Halifax, NS B3H 4J1 Canada

115 At least one strain of the harmful algal bloom genus, DIATOM PROTOPLASTS ARE AMOEBOID Alexandrium, can take up nutrients, specifically nitrate, DURING RECOVERY FROM OSMOTIC SHOCK in the dark during nocturnal descent of diel vertical Pollock, F.1, Pickett-Heaps, J.1 & Schmid, A-M.2 migration (DVM). There is, however, widespread 1School of Botany, University of Melbourne, Parkville, variability among strains of Alexandrium, as shown in Victoria 3052 Australia; 2Department of Plant studies of morphology and toxin composition of isolates Physiology, University of Salzburg from the Gulf of Maine. Our objective is to study the effects of nitrate limitation on a Casco Bay strain of Cells of the diatom Ditylum brightwellii were briefly Alexandrium, focusing on behavior and nutrition as plasmolysed in 0.2-0.4M NaCl and their recovery in sea indicators of nutrient status in the field. The effect of water was followed by time-lapse video microscopy. nitrate availability on an isolate of Alexandrium Spherical protoplasts shrank to about an eighth of the tamarense from Casco Bay, Maine was examined for cell volume and were free within the valve, rotating and physiological and behavioral changes in a 2-m, moving gently. After about 15-20 mins., numerous thermally stratified laboratory water column (tank). active filopodia began to extend randomly from the Temperature ranged from 17 °C at the surface to 7 °C protoplasts. The tips of these ran over the inside of the at 200 cm with a surface irradiance of 400 mmol quanta valve and soon appeared to attach to specific sites m-2 s-1 (14h light:10h dark cycle), identical to a previous around the end of the valve. The filopodia appeared study using a Gulf of St. Lawrence isolate. Like the St. tensile, often pulling the protoplast to one end of the Lawrence strain, the cells maintained a thin surface empty wall before connection was established to the layer, depleting nitrate (initially 50 mM) from the top 20 other end, whereupon it became central. Most cells cm within a few days. Unlike the St. Lawrence strain, then slowly expanded and appeared completely normal which acquired nitrate through nocturnal migration to within about 1.5 hrs. Furthermore, several cells were the nitracline, the Casco Bay cells did not deplete the recorded dividing soon afterwards, so we presume tank of nitrate and showed signs of progressive N recovery is complete. If cells had been dividing at limitation. Calculations show that nocturnal nitrate plasmolysis, they shed their forming valves. Upon uptake was inadequate to sustain a growth rate of 0.3 recovery, if the valves were small, the filopodia did not day-1 as determined from nitrate replete cultures. It is "recognize" them, growing past them and later, when concluded that the Casco Bay isolate is incapable of the two protoplasts inflated, they pushed the nascent obtaining and sustaining growth from nocturnal descent valves aside. Some of these cells initiated completely to the nitracline. new valves, apparently therefore being able to restart valve morphogenesis. If the shed wall was larger, 117 however, filopodia attached to its edge, and the daughter THE DIATOM GENUS TRYBLIOPTYCHUS cells soon expanded and looked normal. These HENDEY: FINE STRUCTURE AND observations show the remarkable resilience to the cells SYSTEMATICS toward osmotic shock. They also indicate that the Prasad, A.K.S.K.1 & Nienow, J. A.2 mature valve has specific anchoring points inside it 1Department of Biological Science, Florida State which the protoplast recognizes and specifically attaches University, Tallahassee, FL USA; 2Biology Department, to. These anchor points are likely to be significant in Valdosta State University, Valdosta, GA USA the spatial control of cell division and morphogenesis. Tryblioptychus Hendey is a diatom genus established to 116 accommodate a small elliptical species with alternating hyaline and areolate sectors on the valve face originally ABSTRACTS 45 decribed by Cleve as Campylodiscus cocconeiformis. Departement de biologie & Centre d'etudes nordiques, Until now, the systematic position of this genus was Universite Laval, Sainte-Foy, QE G1K 7P4 Canada unclear with various authors placing it in Surirellaceae, Actinodiscaceae, and Thalassiosiraceae, families with A series of assays were conducted on the phytoplankton little taxonomic affinity. An abundance of material of a subarctic lake to determine whether short-term identified as Tyrblioptychus cocconeiformis from the F. (hours) temperature and ultraviolet radiation (UVR) Meister collection provided an opportunity to study the effects on photosynthesis were indicative of fine structure of this diatom and, thus, to clarify its photosynthetic and growth responses at longer time taxonomic relationships. The presence of loculate scales (days). A series of short-term experiments (2-4 h areolae with external foramina and internal dome-shaped incubations) showed that photoinhibition under strong cribra, a marginal ring of fultoportulae with three struts PAR was 100-350 % greater in the presence of UVR. and a subcentral fultopotula with four struts, a single A temperature x UVR interaction was evident in one marginal rimoportula with strong external development, experiment with greater net damage at 10 °C, but the and a cingulum composed of perforated bands justify lack of interaction in two other experiments indicated Simonsen's placement of this genus in the that the time scale examined was too short for the Thalassiosiraceae. The affinities of a second species in temperature-dependence of repair processes to be this genus, T. hainansis Voigt, remain undetermined. detected. A series of long-term experiments (8 d) The presence of T. cocconeiformis in samples from showed that over time the photosynthesis-irradiance (P- coastal waters near China, Japan, Vietnam, Singapore, E) parameters deviated substantially from those obtained Sumatra, India and the West Africa indicate that the initially. By Day 7, a and Pmax were 67 and 30% higher species is widely distributed in warm waters. in the -UVR 10 °C treatment relative to +UVR 10 °C, 118 but there was no evidence of increased resistance to LIGHT AND SCANNING ELECTRON photoinhibition, as measured by the b parameter. MICROSCOPE OBSERVATIONS OF AN Contrary to the UVR effect on photosynthesis, growth INTERESTING SYNEDROID DIATOM FROM rates as estimated by changes in chlorophyll a were not FLORIDA BAY, USA significantly different between UVR treatments after 8 Prasad, A.K.S.K.1, Nienow, J. A.2, & Riddle, K. A.1 d. We conclude that acute and chronic responses of 1Department of Biological Science, Florida State photosynthesis to UVR are not the same, and that short- University, Tallahassee, FL USA; 2Biology Department, term photosynthetic responses provide a poor guide to Valdosta State University, Valdosta, GA USA longer term growth effects. Temperature plays a role in the observed UVR response at both time scales. Light microscopic examination of water and net samples from several sites in Florida Bay revealed the presence 120 of large numbers of spindle-shaped synedroid diatoms SYSTEMATICS AND BIOGEOGRAPHY OF THE bearing a superficial resemblance to other spindle- COMPSOPOGONALES (RHODOPHYTA) WITH shaped diatoms, especially Nitzschia longissima (Breb.) EMPHASIS ON FRESHWATER GENERA IN Ralfs, Cylindrotheca closterium (Ehrenb.) Reimann et. NORTH AMERICA al., Toxarium hennedyanum (Greg.) Pelleton, Rintoul, T.1, Sheath, R. G.1 & Vis, M. L.2 Psammosynedra closterioides (Grun.)Round, Department of Botany and Dean's Office, University of Synedropsis hyperborea (Grun.) Hasle et.al. Scanning Guelph, Guelph, ON N1G 2W1 Canada; electron microscope observations of this diatom revealed 2Environmental and Plant Biology, Ohio University, the presence of a single row of small poroid areolae at Athens, OH 45701 USA the valve margin, a single rimoportula near each pole, and 2 to 3 tiers of simple pores on the polae mantle. The rhodophyte order Compsopogonales consists of This combination of features does not match any of the three families: Compsopogonaceae, Boldiaceae and existing generic concepts. Erythropeltidaceae. The first two families are freshwater in their occurrence while the members of the 119 third family are marine. The validity of this order as a TIME SCALES OF PHOTOSYNTHETIC natural monophyletic group was examined using DNA RESPONSE TO ULTRAVIOLET RADIATION sequence data from both the chloroplast (rbcL) and AND TEMPERATURE BY SUBARCTIC nuclear (18S rRNA) genome for representative genera PHYTOPLANKTON of these families and related orders. Both parsimony Rae, R. & Vincent, W. F. and distance analyses weakly support a monophyletic 46 ABSTRACTS compsopogonalean clade excluding the genus Smithora. Rizzo, P. J.1,2 , Morris, R. L.1, & Hastings, J. W.2 A close relationship between the two freshwater families 1Biology Department, Texas A&M University, College is strongly supported. In comparisons of both genes of Station, TX 77843 USA; 2Biological Laboratories, the compsopogonaceaen genera, Compsopogon and Harvard University, Cambridge, MA 02138 USA Compsopogonopsis, sequence divergence was very low We have developed a method for the isolation of intact (0 to 0.66% rbcL in 5 collections and 0 to 0.12% 18S nuclei from Gonyaulax polyedra and G. tamarensis, to in 2 collections). This result suggests that these genera permit characterization of the nuclear basic proteins. should be synonymized. The level of genetic The combination of a very tough theca, and extremely divergence in North America for genera in the fragile nuclear envelope provided the major obstacles in freshwater families (10 collections of this endeavour. However, the availability of intact Compsopogonaceae and 9 collections for the Boldiaceae) nuclei from Gonyaulax will permit many other studies in was assessed using DNA sequence analysis of rDNA addition to the characterization of histone-like proteins internal transcribed spacer regions (ITS1 and ITS2). reported here. The isolation procedure included cell Biogeographic patterns will be discussed. harvest by filtration through Nitex, cell disruption by sonication, and nuclear purification by low-speed 121 centrifugaion and filtration through Nitex. Unlike most PRELIMINARY OBSERVATIONS ON AGE AND dinoflagellates, Gonyaulax nuclei are "C-shaped" rather GROWTH IN LITHOTHAMNION than spherical in morphology, but are similar to other CRASSIUSCULUM, A RHODOLITH-FORMING dinoflagellate nuclei in staining properties with various SPECIES IN THE GULF OF CALIFORNIA dyes, and the presence of permanently condensed Rivera, M.G.1, Riosmena-Rodriguez, R.1 & Foster, M. chromosomes. As in other dinoflagellates, Gonyaulax S.2 nuclei are devoid of histones, but the chromatin does 1Herbario Ficologico, Mar. Biol. Dept. UABCS, La Paz contain histone-like proteins. Thus basic proteins B.C.S. 23080 Mexico; 2Moss Landing Marine Labs, prepared from chromatin of isolated nuclei of both G. Moss Landing CA 95039 USA polyedra and G. tamarensis appear as one major band of about 13,000 daltons in SDS gels. In Western blots, The nongeniculate coralline alga Lithothamnion these histone-like proteins cross-react with antibodies crassiusculum is commonly found as a free-living prepared against histone-like proteins from the rhodolith in the wave-exposed shallow waters of the nonphotosynthetic heterotrophic dinoflagellate southwestern Gulf of California. This species has bands Crypthecodinium cohnii. We conclude that histone-like along the main branch axes suggesting growth is proteins in dinoflagellates are conserved since they are periodic and the bands might be used to determine age similar in a non-photosynthetic heterotrophic and growth. As a part of our ongoing research related dinoflagellate and a typical phototroph. to rhodoliths and their ecology, we have made preliminary observations on the nature of these bands 123 based on their structure in entire plants and on field THE ULTRASTRUCTURE OF GYMNODINIUM growth experiments. Individual plants from different SANGUINEUM: FLAGELLAR APPARATUS AND size classes were tagged, stained with Alizarin and CYTOSKELETON returned to the field. Half of the plants were sampled Roberts, K. R. & Bunnell, A. S. after six months and the rest after twelve months. The Department of Biology, University of Southwestern data indicate that this species grew at a rate of 0.67mm Louisiana, Lafayette, LA 70504 USA per year. There were significant differences among branches within a plant, but not among plants of The large dinoflagellate Gymnodinium sanguineum has different size. Growth was seasonal, with high rates in been studied extensively with serial sectioning and winter-spring and lower rates in summer-fall. This may transmission electron microscopy. The flagellar explain the observed alternating light-dark bands along apparatus consists of basal bodies that are nearly anti- branch axes. The growth rates suggest that larger plants parallel, a broad microtubular root, a striated connective (ca. 15 cm dia.) may be over 100 years old. between the microtubular root and the long transverse striated fiber, diminutive striated collars around each 122 flagellar exit aperture, and a broad striated ventral HISTONE-LIKE PROTEINS FROM ISOLATED connective that connects to the cell's left ventral surface NUCLEI OF THE MARINE DINOFLAGELLATE of the sulcus and to the microtubular root. A lamellar GONYAULAX structure with distinct fibrillar extensions, similar in ABSTRACTS 47 appearance to those of a multi-layered structure (mls), presented abundant paramilon grains. In cultures of E. has been observed within the flagellar apparatus. A gracilis- E. coli, the algae presented a normal shape but large ventral ridge is present and no nuclear connective abundant paramilon. The greatest algal growth was has been observed. Cytoskeletal details previously registered when growing with E. coli. On the other observed with fluorescence microscopy have been hand, we used antibiograms, where different strains detailed ultrastructurally and will also be presented. were exposed to an etilic ether extracts of E. gracilis. The strains used were Pseudomonas aeruginosa, 124 Salmonella sp., Klebsiella sp., Escherichia, APPLICATION OF SINGLE CELL GEL Mycobacterium fortuitum, Mycobacterium gordoneae ELECTROPHORESIS (COMET ASSAY) TO and Staphylococcus aureus. As a result of these DETECTION OF DNA DAMAGE IN PROTISTS experiencies, positive interaction was observed with Rothschild, L. J. & Pearson, N. Klebsiella sp. (inhibition), M. fortuitum and M. N.A.S.A., Ames Research Center, Moffett Field, CA gordoneae - with these two an indution ring appeared 94035 USA first and then and inhibition ones. No answers were detected with the other strains used with this technique. Single cell gel electrophoresis (SCGE) under denaturing We conclude that different interactions can be observed alkaline conditions has proven useful for detecting depending on the methodology employed. The next step single-strand DNA breakage in nuclear genomes of is to analyze the substances involved in these relations individual eukaryotic cells. This method, dubbed and the conditions that determine their liberation. "comet assay" for the cometary form of observed cellular DNA migration, allows visualization and may 126 allow quantification of DNA damage induced in DESIGN STRATEGIES FOR FORECASTING individual nuclei by diverse agents including oxidants, SYSTEMS FOR HARMFUL ALGAL BLOOMS ionizing and -- indirectly through nucleotide excision Schofield, O.1, Glenn, S.1; Kirkpatrick, G.2, Millie, D. repair-associated single-strand breakage - ultraviolet F.3, & Moline, M. A.4 radiation. Adapting published methods for mammalian 1Institute of Marine and Coastal Sciences, Rutgers cells, we have used SCGE to assay UV-induced DNA University, New Brunswick, NJ USA; 2Mote Marine damage in a eukaryotic freshwater alga, Laboratory, Sarasota, FL, USA; 3USDA, Agricultural Poteriochromonas malhemensis, extending the reported Research Service, New Orleans, LA USA; 4Biological application of this technique beyond animals and plants. Sciences Department, California Polytechnic State The potential utility of SCGE in studying DNA damage University, CA USA in diverse photosynthetic eukaryotes will be discussed. A long term objective of the ECOHAB program is to 125 develop the capacity to forecast harmful algal blooms. STUDIES OF THE INTERACTIONS BETWEEN Our research efforts have focused on the development of EUGLENA GRACILIS AND DIFFERENT STRAINS synoptic sampling approaches which can be assimilated OF PATHOGEN MICROORGANISMS into numerical forecasting models and/or be used to Ruiz, L. B., Squadrone, M. & Conforti, V. empirically predict the presence or absence of an algal Facultad de Ciencias Exactas y Naturales, Ciudad taxon. One approach we have been exploring is the use Universitaria, Pab II, Departamento de Ciencias of artificial neural networks which unlike traditional Biológicas, 1428, Buenos Aires, Argentina empirical approaches, are effective at describing complex nonlinear phenomena. This is particularly Studies made in polluted water streams showed that one important when environmental data is used to predict the of the species found was Euglena gracilis presence of a specific species in a heterogeneous algal (Euglenophyta) sharing the habitat with pathogen community. The strengths and weakness of neural bacteria. Our study was aimed to analyze if there was networks in predicting phytoplankton community any interaction between E. gracilis and strains of composition will be demonstrated using several large bacteria isolated from a stream and human pathologies. environmental databases. A second forecasting To evaluate this relation, different assays were carried approach is based on data assimilation into numerical out. Cultures of E. gracilis growing with Klebsiella sp. models. This requires input data and appropriate and other growing with Escherichia coli were made. physical/biological models. Optical data can provide After 48 h., in cultures of E. gracilis-Klebsiella sp., the synoptic data over ecologically relevant scales; however algae changed its shape, turned oval, lost movility and the data acquired provides only bulk signals for the 48 ABSTRACTS optically active constituents within the water. Recent use. In turn, this information has been used to refine optical deconvolution techniques show much promise probe application techniques and highlight needs for and species-specific algorithms have been developed to future research. predict the presence or absence of the toxic red-tide dinoflagellate, Gymnodinium breve. The species- 128 deconvolution technique utilizes fourth derivative IS THE "SPORE WALL" OF CORALLINE RED spectra and a similarity indexes based upon a reference ALGAE A "CALCIUM DEPOSITION MATRIX"? G. breve absorption spectra and the measured Scott, J. L.1, Broadwater, S. T.1 & Murray, S. N.2 phytoplankton community absorption spectra. Data 1Department of Biology, College of William and Mary, from natural populations in the Gulf of Mexico will be Williamsburg, VA 23187 USA; 2Department of used to demonstrate the merits of this approach. The Biological Sciences, California State University, resulting optical data is amenable for data assimilation Fullerton, CA 92834 USA into numerical forecasting strategies. The design and operation of one such data assimilation system Transmission electron microscopy has shown that prior developed for the coastal waters of New Jersey will be to release, mature spores of all investigated red algae are discussed. coated by a presumptive mucilage layer within the sporangial cell wall. Although terminological 127 differences exist concerning the various wall layers of APPLICATION OF DNA PROBES FOR reproductive cells, to our knowledge a true "spore wall" DETECTION OF HARMFUL ALGAL SPECIES IN to the inside of the mucilage coat has not been CULTURED AND NATURAL SAMPLES demonstrated except in tetrasporangia of the coralline Scholin, C. alga Haliptilon studied by Vesk and Borowitzka in Monterey Bay Aquarium Research Institute, Moss 1981. Investigations in our lab of later stages of Landing, CA 95039 USA sporogenesis in approximately 20 genera in six of eight corallinacean subfamilies indicate that a conspicuous A common problem associated with studies of harmful wall layer, whose morphology varies somewhat across algal blooms (HABs) is identifying a particular causative genera, is formed adjacent to the cell membrane in bi- organism as it occurs in nature, especially when rapid /tetrasporangia and carposporangia. Since it is known analysis of a large number of samples is required. that calcification in coralline algae is enhanced by Development and application of species-specific photosynthesis and requires an organic wall matrix molecular probes has long been heralded as the means wherein calcite crystals are deposited, it is our by which one might accomplish this goal with greater supposition that the unique "spore wall" of coralline ease and efficiency than might be possible using algae represents a "calcium deposition matrix" which traditional morphotaxonomic-based techniques. Over can provide the attached spore and young germlings an the past decade considerable effort has been spent early start in thallus calcification. Further studies are developing novel probes for a variety of HAB underway to precisely determine when calcification first organisms and testing their sensitivity and specificity, occurs in the transition from mature spore to young largely in the context of cultured samples. In contrast, germling. comparatively little work has been done to identify the needs of the likely end-user of these probes, to gauge 129 the specificity of the probes in the context of natural THE RATIO BETWEEN ECOLOGICALLY- samples, and to reveal the costs and benefits of different SIMILAR GAMETOPHYTES AND probe application techniques as well as their inherent TETRASPOROPHYTES IN POPULATIONS OF limitations when one considers realistic scenarios of how THE GIGARTINACEAE: DEMOGRAPHIC they might be applied routinely. To address these issues MODELS using Pseudo-nitzschia and Alexandrium as model HAB Scrosati, R.1 & DeWreede, R. E.2 species, existing ribosomal RNA (rRNA) targeted 1CIBNOR - Marine Biology, AP 128, La Paz, 23000 probes were distributed to a number of researchers Baja California Sur, Mexico; 2Department of Botany, studying those organisms in several different labs within The University of British Columbia, Vancouver, BC the US and abroad. This multi-year effort, known as V6T 1Z4 Canada. TACO (Toxic Algae Cook Outs), has revealed numerous insights as to the utility of the probes and In populations of the Gigartinaceae, gametophytes often helped identify certain problems associated with their predominate numerically over tetrasporophytes on an ABSTRACTS 49 annual and/or a whole-habitat basis. A number of important in determining whether a species can maintain hypotheses have been proposed to explain this pattern, space and reach reproductive maturity. Water motion based on the usually-implicit assumption that the and interspecific competition limit the distribution of equilibrium gametophyte:tetrasporophyte (G:T) ratio uprights for some species in this family; endophytes, should be 1 when both reproductive phases are nutrient availability, and desiccation may also be ecologically similar. We present demographic models significant. Species distributions may be set by how that show that the equilibrium G:T ratio differs from 1 some of these extrinsic factors act on dispersal or on when both phases are ecologically similar. Model recently settled spores. Biomechanical studies showed assumptions are that there are no differences in vital that fragmented blades from a low wave impact species parameters (except spore output) between phases. The could survive at a high wave impact site which implied relative spore output represents the simplest possible that it does not disperse to or cannot attach at high case: 1 carpospore is produced every two (female-male) impact sites. Using a comparative ecological approach gametophytes (considering dioecious species), which allows conclusions to be made about how algal species originates 1 tetrasporophyte, and 4 tetraspores are survive in their respective habitats. If this strategy was produced by every tetrasporophyte, which originate 2 combined with studies of gene flow in the female and 2 male gametophytes. Under different Gigartinaceae, our understanding of how genetic combinations of mortality rates (the same for both variation is maintained in algal populations would also phases for each model) and initial G:T ratios, the G:T be enhanced. ratio generally stabilizes around 2.83 after a variable number of iterations of the models. We conclude that 131 the idea of an "expected" G:T ratio equal to 1 for A PROPOSAL FOR A NEW RED ALGAL ORDER, ecologically-similar phases should be abandoned. The THE BALBIANIALES G:T ratios observed in nature would derive from our Sheath, R. G. & Mòller , K. M. simplest possible scenario by differential variations Department of Botany and Dean's Office, College of between phases of spore output, spore viability, Biological Science, University of Guelph, Guelph, ON, sporeling recruitment, reproductive maturation rates, N1G 2W1 Canada reproductive periodicity, reproductive life-span, competitive abilities, resistance to herbivores and The freshwater rhodophyte Balbiania investiens was pathogens, and adult mortality rates, and by possible collected as an epiphyte of Batrachospermum apogamy and apomeiosis. helminthosum in a small stream in Ambelside, England. Unialgal cultures and field collections of Balbiania were 130 analysed in terms of their morphology, ultrastructure THE COMPARATIVE ECOLOGY OF ALGAL and DNA sequences of the rbcL and 18S rRNA genes. SPECIES: A CASE STUDY OF THE The major distinguishing feature of this genus is the GIGARTINACEAE (RHODOPHYTA) production of spermatangia on the tips of specialized, Shaughnessy, F. J. elongate cells. The spermatangia are cut off in a cluster Department of Biological Sciences, Humboldt State together with non-spermatangial cells that are packed University, Arcata, CA 95521 USA with starch granules. The only other rhodophyte genus with this feature is Rhododraparnaldia; the two genera Understanding population differentiation requires are differentiated from each other by the pattern of combining studies from ecology, phylogeny, taxonomy branching. In the parsimony and distance trees of the and gene flow. The objectives of this paper are to two genes analyzed, Balbiania and Rhododraparnaldia summarize the ecology of species in the Gigartinaceae are grouped together on a branch separate from other and, secondly, to point out what kinds of ecological taxa of the Acrochaetiales, Batrachospermales, studies are still needed and how they might be Nemaliales and Palmariales. This branch is well completed. Field studies in this family can be hampered supported by bootstrap resampling. Based on these by an inability to distinguish between morphologically findings, we propose the establishment of a new order, similar species. An examination of Mazzaella splendens the Balbianiales, which includes Balbiania and and M. linearis showed that early developmental stages Rhododraparnaldia. of the annual uprights provide useful vegetative characters, and a common garden experiment indicated 132 that character differences were not due to plasticity. Factors affecting the distribution of uprights are 50 ABSTRACTS

A COMPARISON OF FRESHWATER AND complexes with a broad range of morphological MARINE HILDENBRANDIA (RHODOPHYTA) IN variability. The unifying ontogenetic event is the NORTH AMERICA production of a palisade of photosynthetic structures Sherwood, A. R. & Sheath, R. G. (utricles) by enlargement of branches of a sympodial Department of Botany and Dean's Office, University of filament. Variations on this theme have arisen Guelph, Guelph, ON N1G 2W1 Canada phylogenetically by progressive shortening of the filament between utricles to the point that new utricles The phylogenetic relationships between marine and bud off directly from existing utricles. Several freshwater Hildenbrandia (Rhodophyta) are not well fundamental questions are suggested by the interplay understood. Freshwater Hildenbrandia collections may between this filamentous structure and the spectrum of represent invasions by marine populations into stream species-specific macroscopic forms. For example, what habitats. To test this hypothesis we have employed is the scientific bases that cause the independent primary several comparative techniques to examine 15 filaments of a juvenile Codium to cooperate and start collections of marine and freshwater Hildenbrandia producing a discrete thallus? What causes a group of from Newfoundland to Costa Rica. Morphometric apical sympodial filaments to form two groups, one to analysis of 10 vegetative and reproductive characters the left and one to the right, thus effecting dichotomous was performed using cluster analysis (UPGMA branching? Codium offers challenges for sophisticated algorithm), principle components analysis and one-way research in many fields, including systematics, but the analysis of variance. DNA sequence comparisons of the great difficulty in culturing it in the laboratory and in rbcL and 18S rRNA genes were accomplished using analyzing the taxonomic complexes is frustrating. parsimony and distance analyses. Pit plug morphology was studied using transmission electron microsopy. 134 Morphometrically, the groups of populations are MOLECULAR PHYLOGENETIC POSITION OF separable based on thallus and filament height, as well CHAETOSPHAERIDIUM GLOBOSUM (CHARO- as number of cells per filament. A wide range of DNA PHYCEAE, CHLOROPHYTA) sequence divergence values was found for the rbcL Sluiman, H. J. & Guihal, C. gene, ranging from 0.2% to 26.9%. Both the molecular Royal Botanic Garden Edinburgh, Edinburgh, Scotland phylogenies and the morphometric phenograms show EH3 5LR UK distinct groupings of marine and freshwater populations. However, the pit plugs of marine and freshwater We sequenced the 18S rDNA of Chaetosphaeridium Hildenbrandia populations both have one cap layer, globosum (Nordst.) Klebahn, a microscopic green indicating that the two groups most likely share at least freshwater epiphyte, in order to assess its phylogenetic common ancestry. affinities in the Chlorophyta. Cultures were harvested after overnight air drying at –18 oC and DNA was 133 extracted and purified using either chloroform and CODIUM, A GENUS OF CHALLENGE AND Nucleon Phytopure silica, or the Qiagen gel purification FRUSTRATION method. Many different PCR primer combinations were Silva, P. C. tested but only two combinations yielded a product that Herbarium, University of California, Berkeley, CA could be sequenced using dye termination with the ABI 94720 USA 377 sequencer. A phylogenetic analysis of a broad sampling of green algal taxa and Chaetosphaeridium (a Although the coenocytic green algal genus Codium is total of 1681 nucleotide positions were included in our represented in almost every local flora, its alignment) confirmed that this alga is a member of the morphological and taxonomic complexity is not widely Charophyceae (Streptophyta) as earlier microscopical appreciated. Ironically, the best known entity is C. studies had suggested. However, according to our 18S fragile subsp. tomentosoides (van Goor) Silva, a rDNA gene trees and contrary to expectations (based on widespread weed that probably represents a single the ultrastructure of the zoospores and the presence of a genotype. The diversity of Codium continues to be unique type of setae) Chaetosphaeridium is not closely revealed by ongoing studies of new collections. For related to Coleochaete. Instead, it represents an early example, the number of species recognized in the branch in the streptophyte lineage that originates Hawaiian Islands has increased from 6 in 1952 to 15 immediately after the emergence of the basal-most today. About 50 (nearly half) of all species of Codium charophycean clade, viz. the Charales. are clearcut, while the remainder are members of Chaetosphaeridium is the sister-group of a clade formed ABSTRACTS 51 by Klebsormidium, Coleochaete, Chlorokybus, SAMPLES OF THE BROWN TIDE Zygnematales and bryophytes. The node that joins all MICROORGANISM, AUREOCOCCUS these taxa has a bootstrap support value ranging between ANOPHAGEFFERENS 75 and 100%, depending on the algorithm used and on Stabile, J.1,2, Rosko, J.1 & Wirgin, I.1 the taxa included in the analysis. The same tree topology 1New York University Medical Center, Nelson Institute is found irrespective of the tree building algorithm used. of Environmental Biology, Tuxedo NY 10987 USA; No Group I introns are present in the 18S rDNA of 2Iona College, Department of Biology, New Rochelle NY Chaetosphaeridium. 10987 USA

During the past decade blooms of the brown tide 135 microalga, Aureococcus anophagefferens, have occurred ION FLUXES DURING POTENTIATION AND sporadically in Peconic and Gardiners Bay in eastern GAMETE RELEASE IN THE FUCOID ALGA Long Island, NY and in Great South Bay along the PELVETIA COMPRESSA (J. AGARDH) DE TONI. south shore of Long Island. Blooms of brown tide vary Speransky, V. V.1, Brawley, S. H.1, McCully, M. E.2 annually in the timing of their onset, duration and 1School of Marine Sciences, University of Maine, intensity. Additionally, spatial heterogeneity in the Orono, ME 04469 USA; 2Carleton University, Ottawa, onset of blooms is seen among these sites. We ON K1S 5B6 Canada. hypothesize that temporal and spatial variability in bloom characteristics is due to underlying genetic Fucoid algae achieve high fertilization success by variation among populations of A. anophagefferens. synchronous gamete release after potentiation in light This hypothesis was tested by sequence analysis of the and low water motion. In Pelvetia compressa, massive internal transcribed spacer region (ITS) of rDNA. A. release is triggered by darkness. We used X-ray anophagefferens- specific PCR primers were developed microanalysis of hydrated, rapidly-frozen receptacles to and used to amplify brown tide ITS sequences directly investigate whether osmomechanical forces are involved from water samples and laboratory cultures. PCR in gamete release. Receptacles were frozen with LN2- products from individual water samples were cloned in cooled copper pliers and held in liquid nitrogen until pCR2.1 and sequenced. Sequence results from up to 20 planed to a smooth face in a cryo-microtome, then clones/water sample showed that there are high levels of examined at -170 oC. When potentiated, all cells except DNA sequence variation among prebloom and bloom those of the epidermis and mature oogonia had water samples collected in 1995 and 1997. Genetic accumulated high K+ levels (up to 1.2 M in hair cells). variation in the ITS region was also observed within Cl- was distributed evenly between cells and the single laboratory cultures of A. anophagefferens. These extracellular matrix in both medulla and cortex. An results indicate that genetic variation is high both in efflux of K+ from hair cell filaments occured within the environmental samples and in individual laboratory first 2 to 5 min of darkness. This appeared to occur as a cultures and suggest that this variability may be wave, beginning in distal portions of filaments near the important in controlling the onset and duration of brown pore and ending in proximal portions at the base of the tide blooms. Additionally, this genetic variation should conceptacle. Simultaneously, K+ efflux was observed be considered when conducting physiological from the cortical and medullary cells into the experiments on these laboratory cultures. extracellular matrix. The pattern of Cl- flux was similar to that of K+. The pre-dark distribution of K+ and Cl- 137 was restored by the beginning of actual gamete release CONCHOCELIS PHYSIOLOGICAL ECOLOGY OF (6-9 min darkness). We propose the following model: SIBLING PORPHYRA SPECIES FROM NORTH 1) Membrane depolarization develops as a downstream AMERICA effect of the onset of darkness in potentiated receptacles; Stekoll, M. S. 1, Wilkes, R.2 & Yarish, C.2 2) K+ efflux into the extracellular matrix causes water 1Juneau Center, School of Fisheries and Ocean uptake and rapid swelling of the gel; 3) gametangia are Sciences, University of Alaska, Juneau, AK 99801 detached and released by mechanical force during gel USA; 2 University of Connecticut at Stamford, Stamford, transformation. CT USA

136 The conchocelis stages of two pairs of putative sibling INTRASPECIFIC VARIATION AMONG species of the red seaweed Porphyra were compared in CULTURES, PREBLOOM, AND BLOOM laboratory growth experiments. The pairs were 52 ABSTRACTS

Porphyra amplissima-Porphyra cuneiformis and significantly greater inside these beds in contrast to Porphyra linearis-Porphyra pseudolinearis. The first adjacent sandy flats. Lab and field experiments named species of each pair is considered to be North investigated the mechanism of increased invertebrate Atlantic species and the latter are North Pacific species. species richness by examining larval settlement Each pair of sibling species was monitored for growth preferences. Greater settlement of bivalve larvae on under varying conditions of light intensity and living rather than dead coralline surfaces suggest that temperature using a gradient table. Light values tested living coralline substrates may enhance subtidal mollusk were 10, 20 and 40 mmoles photons-1 m-2 s-1. Four populations. Associated organisms may also depend on temperatures of 5, 10, 15 and 20 oC were tested. For the presence coralline structure and substrate. both pairs the North Pacific species grew much faster initially. The temperature for maximum growth was 10 139 oC for P. pseudolinearis at all light intensities, and 15 WHY RED ALGAE LACK TRUE TISSUE oC for P. linearis. Porphyra amplissima and P. DEVELOPMENT: A FUNCTIONAL AND o cuneiformis both showed optimal growth at 10 C. EVOLUTIONARY HYPOTHESIS There were differences in response to light intensity Stiller, J. W. & Hall, B. D. between the North Atlantic and North Pacific species. Department of Botany, University of Washington, Growth of the North Atlantic species appeared to be Seattle, WA 98195 USA independent of light intensity. The morphology of P. pseudolinearis was dependent on environmental Despite their great antiquity based on fossil and o parameters. At 15 C the habit of the conchocelis of molecular evidence, and their broad diversity in this species became compact and elongate. None of the morphological forms and life histories, the red algae species became conchosporangial under the test never evolved true tissue differentiation. The functional conditions. and evolutionary bases for this feature of the Rhodophyta remain largely unexplored. In seeking 138 molecular correlates with developmental complexity, we CORALLINE ALGAL REEFS: COMMUNITY performed sequence analyses on a gene required for the DYNAMICS STRUCTURED BY SUBSTRATE OR expression of all nuclear encoded proteins. Here we STRUCTURE? report comparisons of the 3' distal sequences of the gene Steller, D. L. encoding the largest subunit of RNA polymerase II University of California at Santa Cruz, Santa Cruz,CA (RPB1) from two divergent rhodophytes, Porphyra 95064 USA yezoensis Ueda and Bonnemaisonia hamifera Heriot. In multicellular green plants and animals this region of the This study investigated the influence of coastal coralline RPB1 gene encodes the C-terminal domain (CTD) that populations to the structuring of nearshore subtidal acts as an organizing center for much of the complex ecosystems through the addition of coralline structure. control over mRNA transcription that is needed for the Unattached species of coralline algae, Lithophyllum differentiation and development of complex tissues. A margaritae and Neogoniolithon sp. are widely CTD is not present in either red algal sequence. The distributed in the nearshore coastal environments in the phylogenetic and functional implications for this Gulf of California, Mexico. Better known as difference in red algal polymerase II will be discussed. rhodoliths, these algae form extensive beds of a living coralline matrix over soft sandy bottoms that cover up to 100% of the seafloor. These beds are dynamic and can be relocated by currents and storms. Population size 140 increases by 'reproduction' via fragmentation and spore OKADAIC ACID AND ITS ECOLOGICAL ROLE settlement and decreases from mortality primarily due to IN THE BENTHIC DINOFLAGELLATE physical disturbance. Preliminary field growth rates COMMUNITY measured from spore settlement experiments result in Sugg, L. M. & Van Dolah, F. M. average growth rates in Neogoniolithon sp. of 5.11 mm Graduate Program in Marine Biology, University of -1 year . Development of conceptacles from newly settled Charleston & Marine Biotoxins Program, NOAA, spores were observed within a 9 month settlement National Ocean Service, Charleston, SC 29412 USA experiment. These algal beds enhance nearshore ecosystems by adding available structure of a settlement Serine/threonine protein phosphatases are regulatory enhancing coralline surface. Species richness is enzymes critical to growth and replication in eukaryotes. ABSTRACTS 53

Okadaic acid (OA), a potent ser/thr protein phosphatase species of Ulva and Enteromorpha. Sequence analysis inhibitor has been well studied in vertebrates. of complete ITS 1 & 2 sequence data revealed 5 well However, little is known about the role it plays in the supported species complexes in the Ythan estuary, ecology of its producer, the benthic dinoflagellate morphologically identified as E. intestinalis, E. Prorocentrum lima. The frequency and diversity of compressa/E. usneoides, E. prolifera, E. linza and E. toxins produced by benthic dinoflagellates suggests that pseudolinza. Furthermore, the inferred phylogenies toxin production may play a role in competition between suggested that neither Ulva nor Enteromorpha is algal species. To assess the role of OA in growth monophyletic; thus, suggesting that thallus morphology competition, individual cultures of dinoflagellate species is not a valid character to distinguish the two genera. which co-occur with P. lima were grown in medium preconditioned by P. lima. We found that exudates 142 from P. lima inhibited the growth of three of these CHATTONELLA SUBSALSA (RAPHIDO- species. In vitro protein phosphatase assays PHYCEAE), A POTENTIALLY HARMFUL ALGA demonstrated that all four dinoflagellate species possess IN THE SALTON SEA, CALIFORNIA protein phosphatases which are inhibited by exogenous Tiffany, M. A., Hurlbert, S. H. & Barlow, S. B. OA at concentrations similar to mammalian systems Department of Biology, San Diego State University, San (IC50 ~5nM). When treated in culture for 24 hours Diego CA 92128 USA with either purified OA or medium preconditioned by P. lima, dinoflagellate protein phosphatase activity was The Salton Sea, the largest lake in California, with a substantially inhibited. However, P. lima salinity of approximately 46 g L-1, has been subject to preconditioned medium (~5nM OA) had greater large die-offs of both birds and fish. In 1997, the growth inhibitory action than even 1uM OA. To raphidophyte Chattonella subsalsa was detected in determine whether its growth inhibitory action was plankton samples from the Salton Sea and its identity independent of its phosphatase inhibitory activity, the confirmed by transmission electron microscopy. medium was fractionated by HPLC and the fractions Chattonella was present at least from April 15, to were tested for the ability to inhibit growth and protein November 25, 1997 with maximal densities of 434 phosphatase activity. We found that the two actions do cells/ml occurring on June 3. The appearance of not co-elute. These results suggest that although OA Chattonella seems to be related to the water temperature has growth inhibitory potential against other microalgae, reaching approximately 20 °C. Midlake surface it does not appear to serve an allelopathic function temperatures reached a maximum of 34.3 °C on Sept. against co-occurring dinoflagellates. 6, 1997 and declined to about 20 °C on Nov. 25, 1997, at which time Chattonella densities also declined. At 141 the height of the algal population increase in June 1997, MOLECULAR PHYLOGENETIC ANALYSIS OF Tilapia fish gills examined by scanning electron ULVA AND ENTEROMORPHA (ULVALES, microscopy showed extremely swollen tips of filaments CHLOROPHYTA). and fused second lamellae. Tilapia observed at the Sea Tan, I. H. & Sluiman, H. J. during this time period appeared to be "gulping" at the Royal Botanic Garden Edinburgh, Edinburgh, Scotland water surface prior to death. Algae in the genus EH3 5LR UK Chattonella have caused fish mortality in Japan, Tasmania, Algeria and the Malabar coast of India. In We inferred phylogeny from comparisons of DNA 1997, major fish kills occurred in January-February, sequence data among selected members of the Ulvales May and September at the Salton Sea. Chattonella was including Ulva and Enteromorpha. Both Ulva and present at high concentrations for the latter two fish kills Enteromorpha are important indicators of eutrophication and may be implicated as the causative agent. in marine and estuarine ecosystems; further, they are also significant fouling seaweeds. Their inter- and 143 intrageneric classifications are both controversial and OPTIMIZATION OF MICROALGAL questionable, primarily, due to the lack of reliable PRODUCTIVITY OUTDOORS: USE OF AN ON- taxonomic characters. The two objectives of this study LINE CHLOROPHYLL FLUORESCENCE were 1) to determine the range of Enteromorpha species TECHNIQUE responsible for causing substantial seasonal algal mats Torzillo, G. (green tides) in the Ythan estuary, Aberdeenshire, Centro di Studio dei Microrganismi Autotrofi Piazzale Scotland, and 2) to infer phylogeny among selected delle Cascine, 27, 50144 Firenze, Italy 54 ABSTRACTS

processes. The cellular mechanisms which mediate The increasing interest in algal biotechnology for the phased cell division are not understood, nor are production of high value products prompts the mechanisms known which might release cells from this application of on-line measurements to monitor and circadian control to result in ‘explosive’ rates of growth. control the growth parameters and to get rapid evidence In this study we sought to identify mechanisms of unfavorable conditions affecting the performance of regulating the cell cycle in the Florida red tide the culture. Since environmental stress affects the dinoflagellate, Gymnodinium breve. Growth rates of function of photosystem II (PSII), directly or indirectly, 0.2 to 0.5 division day-1 observed in both laboratory and the use of chlorophyll fluorescence can represent a field populations of G. breve are not sufficient to useful tool to investigate the stress response mechanism account for its dominance in the water column. In both and to quantify the effect of stress on the productivity of laboratory and field populations, we found that the cell the organism growing under rapidly changing cycle of G. breve is phased to the diel cycle, with S- environmental conditions such as those usually found phase beginning during the light phase and mitosis outdoors. An on-line chlorophyll fluorescence occurring during the dark. The dark/light transition technique, based on the saturating pulse method to appears to serve as the entraining signal. G. breve assess the performance of the outdoor culture of the possesses the eukaryotic cell cycle regulator, cyclin cyanobacterium Spirulina grown in closed tubular dependent kinase (CDK), as identified by photobioreactors, has been developed and tested. immunoblotting and reversible inhibition of cell cycle Diurnal changes in maximum photochemical yield progression by olomoucine, a specific inhibitor of (Fv/Fm) and effective quantum yield of PSII were CDKs. Current work on signaling events which regulate measured in outdoor cultures grown under different cell cycle progression will be discussed. stress conditions (e.g. low temperature, high oxygen concentration, high oxygen concentration plus low temperature), using a portable pulse-amplitude- fluorometer. The results indicate that changes in the 145 biomass yield of the cultures correlate well with changes PLASMA MEMBRANE FLUIDITY ANALYZED IN in the daily integrated value of the estimated electron CELLS EXPOSED TO VOLATILE AROMATIC transport rate (ETR) through the PSII (dF/F'm x Photon HYDROCARBONS USING THE FLUOROPROBE Flux Density). ETR has proved to be a simple and DIPHENYLHEXATRIENE reliable parameter to be used in estimating the VanPutte, R. D. & Patterson, C. O. photosynthetic performance of outdoor cultures of Department of Biology, Texas A&M University, College Spirulina and to reach rapid decisions concerning their Station, Texas 77843 USA management. Crude oil is toxic to phytoplankton. The most toxic 144 components are volatile aromatic hydrocarbons (VAH; CELL CYCLE REGULATION IN THE FLORIDA benzene, toluene, xylene, etc.). However, mechanisms RED TIDE DINOFLAGELLATE, GYMNO-DINIUM of toxicity at the molecular level are not clear. We have BREVE previously reported data supporting our hypothesis that Van Dolah, F. M. toxicity of VAH is due to disruption of optimal physical Marine Biotoxins Program, Center for Coastal state of cytoplasmic membranes. These data suggest Environmental Health & Biomolecular Research, that VAH act as lipid solvents, altering fluidity of National Ocean Service, Charleston, SC 29412 USA cytoplasmic membranes. We now present more direct evidence that changes in membrane fluidity occur during Many dinoflagellates display phased cell division, in VAH exposure. The fluorescent probe which mitosis is restricted to a narrow window of time diphenylhexatriene (DPH) was utilized. Optimal during either the light or dark phase of the diel cycle. conditions were determined for entry of DPH into This circadian regulation may impose a maximum plasma membranes of intact microalgal cells. division rate of 1 division day-1. Thus, an unresolved Subsequently, cells pre-incubated with DPH were question is whether dinoflagellate blooms result from exposed to increasing concentrations of various VAH. events which trigger explosive growth rates, or if cells Our data indicate that with increasing concentrations of replicate at a relatively constant rate, with blooms VAH, membrane fluidity increases in a dose-dependent resulting from advection and subsequent maintenance of manner. However, VAH concentrations required to dense cell populations by physical or biological elicit changes in membrane fluidity as detected by DPH ABSTRACTS 55 fluorescence were greater than those VAH examined on a monthly basis for one year. Physical and concentrations previously shown to produce changes in chemical properties of the streams were measured membrane lipid (fatty acid) composition. These including pH, conductance, metal concentration, experiments provide clear evidence showing one average current velocity, width and depth. Macroalgal mechanism of VAH toxicity is disruption of the taxa were collected and percent cover estimated. structural integrity of plasma membranes. A model will Diatoms were sampled from the riffle area and be introduced incorporating data from all these subsequently identified and enumerated. A dendrogram experiments serving to illustrate the toxic mechanism of the physical and chemical properties showed the three and the means by which algal cells adapt to sub-lethal AMD impacted streams grouped together and the five VAH exposure. slightly impacted streams grouped with the two pristine streams sampled. Principal components analysis (PCA) 146 revealed pH, conductance, aluminum and silica to be the A CRITICAL APPRAISAL ON SOME most influential parameters separating the severely TRADITIONAL CRITERIA AND CURRENT impacted AMD streams from the other sites. Among PROCEDURES IN THE TAXONOMIC the low impact and pristine sites, phosphorus and TREATMENT OF OEDOGONIALES maximum stream width played the greatest role in (CHLOROPHYCEAE) grouping of streams. AMD streams had either no Velez, C. G. macroalgae or were dominated by Klebsormidium sp., Departamento de Ciencias Biologicas, Facultad de which appears to be an indicator of poor water quality. Ciencias Exactas y Naturales, Universidad de Buenos The other streams varied in macroalgal species richness Aires, Buenos Aires, Argentina with season and water quality. Diatom taxa were fewest in AMD streams. Species richness was highest in Identification of taxa within the Oedogoniales is largely streams draining reclaimed coal mines. The pristine based on morphology of sexually-mature reproductive streams were intermediate. It appears that the diatom structures. Taxonomic criteria were established during species richness in streams along this gradient, AMD - the nineteenth century, and generalized in their use after reclaimed - pristine, support the intermediate Hirn's (1900) monograph, the nomenclatural point of disturbance hypothesis. departure of the order. However, the validity of these characters currently considered of taxonomic value has 148 not been a subject of reviewing up to date. In this work A MOLECULAR INVESTIGATION OF THE a critical appraisal based on culture and ultrastructure SYSTEMATIC RELATIONSHIP AMONG evidence derived from the study of twenty-four taxa is SIRODOTIA SPECIES (BATRACHOSPERMALES, presented. The following characters are considered: 1) RHODOPHYTA) IN NORTH AMERICA. number of oogonia in series, 2) type and position of Vis, M. L.1 & Sheath, R. G.2 oogonia opening, 3) apical cell morphology, 4) types of 1Environmental & Plant Biology and Molecular & Cell dwarf males, and 5) vegetative cell morphology. Biology Program, Ohio University, Athens, OH 45701 Additionally, the fact that many uncomplete descriptions USA; 2Department of Botany and Dean's Office, College of taxa could be the result of occurrence in nature of of Biological Science, University of Guelph, Guelph, female apomictic populations (species?) is vindicated. ON N1G 2W1 Canada Future and perspectives of systematics study of the Oedogoniales is discussed. Three morphologically delineated Sirodotia species, S. suecica, S.tenuissima and S. huillensis, are recognized 147 in North America. The rDNA internal transcribed A COMPARISON OF ALGAL DIVERSITY spacer (ITS), RUBISCO large subunit (rbcL) and rbcL- AMONG POLLUTED, RESTORED AND NON- S spacer DNA sequence were employed to investigate POLLUTED STREAMS IN SOUTHEASTERN the systematic relationships among these species. A OHIO total of six populations were sampled comprising the Verb, R. G. & Vis , M. L. following: S. suecica from Rhode Island and Labrador, Environmental and Plant Biology, Ohio University, S. tenuissima from Rhode Island and S. huillensis from Athens, OH 45701 USA Texas, Mexico and Costa Rica. The sequence data for the nuclear and plastid DNA revealed little variation (< Ten streams along a gradient from acid mine drainage 1% sequences divergence) among the S. suecica and S. (AMD) (3 to 3.1 pH) to pristine (6.7 to 7.1 pH) were tenuissima populations. This result suggests that S. 56 ABSTRACTS suecica and S. tenuissima are conspecific and by paddle wheels and lined by some kind of a plastic morphological characters used to distinguish these liner. In the case of Spirulina the ponds are raceway species are not phylogenetically informative. Sequence shaped and vary is size from 0.1 to 0.5 Ha. The variation among S. huillensis populations was < 1% in Chlorella ponds are round with distinct mixing devices the plastid DNA sequences. Between S. suecica and S. and deeper then the Spirulina ponds. The intensive huillensis there was 5% divergence in the combined production of Dunaliella is carried out using similar rbcL and spacer region. ITS sequence data for ponds to the one developed for the Spirulina production, populations within S. huillensis was variable. In while most of the Dunaliella production is carried out in addition, the ITS sequences between S. huillensis and S. large deep lagoons in an extensive mode of production. suecica diverged significantly. From this research we It is most likely that each solution represents a trade-off conclude that S. huillesis and S. suecica are valid between the special requirements of the production species. system, the know-how available to the producers at the time of construction and the local costs of the different 149 components. Yet it is clear that the open pond represent THE PH TOLERANCE OF CHLAMYDOMONAS a very limited solution for the need of this developing APPLANATA AND CHLAMYDOMONAS ACIDO- biotechnology so as to enable growing more species of PHILA (VOLVOCALES, CHLOROPHYTA) algae at a more diverse environment and at a better Visviki, I. controlled system. The future of algal biotechnology Biology Department, College of Mount Saint Vincent, rests, to a large extent, on two factors: a) The ability to Manhattan College, Bronx, N.Y 10471 USA reduce costs of production. b) The development of The effects of H+ ions on the growth and ultrastructure suitable closed photobioreactors. of two chlamydomonads were examined. Growth was determined by measurements of the optical density, 151 while cytological changes were quantified via GREEN TIDE ALGAE OF THE PADILLA BAY morphometric analysis of electron micrographs. Both ESTUARY, WASHINGTON species exhibited wide tolerance growing at pH values Waaland, J. R. & Hayden, H. S. ranging from 8.4 to 3.4. Optimum growth was Department of Botany, University of Washington, observed at 8.4 to 6.4. At pH 4.4, Chlamydomonas Seattle, WA 98195 USA applanata cell size decreased. At pH 3.4 the effects were quite dramatic and included cell death, formation Chlorophytic macroalgae were collected in August and of large palmelloid colonies, loss of motility, abnormal September 1996 and April through August 1997 at six cell division, increase in the volume of the vacuome and sites in the Padilla Bay Estuary of Washington State and appearance of akinetes. C. acidophila cells increased in identified to species using morphological and molecular volume at both pH 4.4 and 3.4. Exposure to the latter characters. Based on morphological identification, H+ ion concentration resulted in inhibition of autospore fourteen chlorophytic macroalgal species were found, release and a significant decrease in chloroplast volume including representatives of Acrosiphonia, Blidingia, accompanied by an increase in vacuolar volume. At this Enteromorpha, Rhizoclonium, Ulva, Ulvaria and pH value cellular contents appear darker and increased Urospora. A different assemblage of species was found autolysis is apparent. The implications of these results among and within sites during each collection while the are discussed. Furthermore, possible mechanisms of number of species at all sites peaked in May and June tolerance are investigated. 1997. Preliminary molecular analysis using restriction digests of the 5.8s coding region and flanking internal 150 transcribed spacers of nuclear rDNA was carried out on MASS CULTURING OF MICROALGAE; FROM individuals of Enteromorpha prolifera, Enteromorpha OPEN PONDS TO CLOSED SYSTEMS linza and Ulva fenestrata. Morphological and molecular Vonshak, A. data are consistent for E. prolifera individuals, but are Microalgal-Biotechnology, J. Blaustein Institute for inconsistent for E. linza and U. fenestrata individuals. Desert Research, Ben Gurion University, Sede Boqer Digestion patterns suggest that gene flow may be campus 84990 Israel occurring among these species and raises questions about the current taxonomy and systematics of In the attempt to design a cost effective culturing system Ulvaceae. These questions will be explored in a cladistic suitable for outdoor mass culturing of microalgal most analysis using DNA sequence data from introns in of the producers use shallow ponds intensively mixed chloroplast trnL and nuclear RNA Polymerase II genes. ABSTRACTS 57

Molecular studies have shown that green algae and land 152 plants share a common ancestor, and charophycean THE EUGLENA PHOTORECEPTOR: A 3D green algae are the closest relatives of land plants. CRYSTAL OF AN OPTICALLY BISTABLE Some charophycean algae have a phragmoplast-mediated INTEGRAL MEMBRANE PROTEIN cytokinesis, the type basic to all land plants but not Walne, P. L. 1, Barsanti, L.3, Passarelli, V. 3, Verni, F. present in most other green algae. Inexplicably, the 2 & Gualtieri, P. 3 phragmoplast-type-cell division has been documented, 1University of Tennessee, Knoxville, TN 37996 USA; via transmission electron microscopy in Cephaleuros 2University of Pisa Ecology Department, Italy; 3CNR- parasiticus Karsten, a trentepohlean alga. Molecular Biophysics Institute, Pisa, Italy data indicate that the Trentepohliales (subaerial green algae) are not in the charophycean lineage, but rather The naturally occurring crystalline photoreceptor of are in or are very closely related to the Ulvophyceae Euglena represents perhaps one of the most intriguing (Chlorophyta). The present study was undertaken to structures in biology. This ancient eukaryote uses a determine if the appearance of a phragmoplast in simple, yet sophisticated system as a light detector—a Cephaleuros represents an anomaly in the trentepohlean single locomotory consisting of an axoneme, a group. Immunofluorescent cytological techniques were paraxial rod and a basal paraflagellar swelling (the used to document cell division in Trentepohlia odorata photoreceptor) which lies in a reservoir adjacent to an (Wiggers) Wittrock. This study clearly revealed a orange-red cytoplasmic stigma. Earlier, Gualtieri phragmoplast-type cell division in T. odorata, thus suggested that the Euglena photoreceptor is a crystal of offering further proof that this type of division is single membrane proteins and interpreted the structure characteristic of the Trentepohliales. The evolutionary as a 3D crystal, which we have since shown to have significance of phragmoplast-mediated cell division in dimensions of 1.0 x 1.5 x 0.7 mm and have confirmed higher plants has been appreciated for many decades. its structure by freeze-fracture electron microscopy. Further investigation of the little-studied The dimensions of the monoclinic unit cell of a single Trentepohliales, which represent the conundrum of crystalline sheet are ca. 50 Å x 40 Å, and the height of "chlorophyte" algae having "charophyte" cell division, the integral membrane protein is ca. 70 Å. Since no might provide a key to unraveling the evolutionary symmetry but the inversion is observed in the Fourier history and development of the diverse microtubular transform, the plane group of the crystal sheet should be systems in the fundamental process of cytokinesis, P11, and the 3D cell appears to be triclinic. The information which is crucial to a full understanding of transmembrane protein is suggested to be rhodopsin- green plant evolution. like, and recent data show that an antibody against recombinant opsin recognizes a 30 kd protein in the 154 Euglena photoreceptor. Our data further show that this CAN THE AQUACULTURED, NON-INDIGENOUS rhodopsin undergoes light conformational changes, i.e., RED ALGA, PORPHYRA YEZOENSIS, RECRUIT repeated and reversible fluorescence changes with a IN EASTPORT, MAINE? determinate kinetics, results suggesting that the protein Watson, K. L.1, Cheney, D. P.1 & Levine, I. A.2 possesses optical bistability. The very high quantum 1Marine Science Center, Northeastern University, East yields of the forward and reverse reactions are nearly Point, Nahant, MA 01908 USA; 2Coastal Plantations identical and close to unity. International, Portland, ME 04101 USA Coastal Plantations International is in its 8th year of 153 commercially farming Porphyra yezoensis, an PHRAGMOPLAST-MEDIATED CYTOKINESIS IN introduced species of nori, in Cobscook Bay, Maine. A TRENTEPOHLIA ODORATA (CHLORO-PHYTA): preliminary survey found some limited evidence of P. AN IMMUNOFLUORESCENT CYTO-LOGICAL yezoensis recruitment at a farm site during the growing STUDY season, but no evidence of over-wintering. The current Waters, D. A.1, Brown, R. C.2, LÙpez-Bautista, J. M.1, study examines the potential ecological impact of & Chapman, R. L.1 farming P. yezoensis at a second site. Surveys of the 1Department of Biological Sciences, Louisiana State intertidal area surrounding this site for P. yezoensis University, Baton Rouge, LA 70803 USA; 2University of recruitment and survival are being conducted using Southwestern Louisiana, Lafayette, LA USA artificial (synthetic netting used in the commercial growing of nori) and natural substrates (tagged macroalgae for epiphytic settlement and 10 meter 58 ABSTRACTS transects of the substrata). Porphyra species are being MARINE SEDIMENT STABILIZATION BY identified by microscopic examination and isoenzyme MICROORGANISMS : THERE’S MORE TO IT electrophoresis. P. yezoensis has not been positively THAN MEETS THE EYE! identified in any transect samples to date. Five putative Wigglesworth-Cooksey, B. & Cooksey, K.E. P. yezoensis were identified on the artificial substrates Department of Microbiology, Montana State University, collected in November. Four of these potential exotics Bozeman, MT 59717 USA were recruited at a single location, and this site effect is being further investigated by tracking water flow The role of microorganisms in the mechanical patterns. In November, strands of netting seeded with stabilization of marine littoral sediments is not clear. P. yezoensis were attached to artificial substrates and Previous investigations have highlighted either the role allowed to overwinter. In March, P. yezoensis was not of bacteria to the exclusion of the algal contribution, or found on the artificial substrates or the seeded strands. vice versa. Since both bacteria and algae [notably The inability of P. yezoensis to overwinter is being diatoms] are abundant in these sediments and both are investigated in laboratory freezing tolerance known to produce potentially sediment particle - binding experiments. The potential for competition between P. extracellular macromolecules, it is not likely that the yezoensis and local Porphyra species is being evaluated contribution of one or the other can be discounted. through measurements of photosynthetic capacity and However, what is more interesting to the phycologist is comparative growth studies. that the role of diatoms in the stabilization process also is not clearly understood. Most studies have involved a 155 group of undefined organisms in their natural setting or PHENOLOGICAL AND LIFE HISTORY STUDIES have utilized a single organism in a laboratory OF ANTITHAMNIONELLA FLOCCOSA simulation. Our work, using several axenic cultures (CERAMIACEAE, RHODOPHYTA) FROM isolated recently from False Bay, San Juan Is., WA, NEWFOUNDLAND shows that the concept that all diatoms from the same Whittick, A. environment make similar contributions to the Department of Biology, Memorial University, St. stabilization process is false. Motile species of diatoms John's, NF A1B 3X9 Canada. [epipelic] are assumed to contribute to sediment stabilization as a result of their secretion of a motility Antithamnionella flocossa is widely distributed in both polymer which binds the particles together to form the eastern and western North Atlantic. In aggregates and the non- motile species [episammic] by Newfoundland, it is commonly attached to stable rocky making bridging polymers. We find that no such substrates in the immediate subtidal. Detailed distinction exists. While motility is fundamentally a phenological studies show its presence throughout the stochastic process, we have shown that this phenomenon year, but with considerable die back in August and can be a directed response [e.g. cellular dispersal] that is September. In some localities, and some years, only probably the result of cell-cell signaling and is sterile and tetrasporophyte plants are found. Other dependent on the growth history of the cells populations show that fertile male gametophytes and [temperature, light level]. female gametophytes bearing carposporophytes occur predominantly between November and February. 157 Fertile tetrasporophytes show a seasonally bimodal THE ROLE OF SUSPENDED SEDIMENT ON distribution, being fertile predominantly between CELL MORPHOMETRY IN CLADOPHORA October and March, and in June and August. At other GLOMERATA IN THE COLORADO RIVER, USA times, sterile plants predominate. Cytological and Wilson, K. P., Shannon, J. P., Blinn, D. W. & culture studies suggest that although the species has a Benenati, P. L. basic Polysiphonia-type life cycle, vegetative Department of Biological Sciences, Northern Arizona reproduction and perennation are common. It also University, Flagstaff, AZ, 86011 USA seems that meiosis can frequently fail and tetrasporophytes may regenerate tetrasporophytes. We examined the role of suspended sediments on the Summer temperatures appear restrictive with little or no cell morphology of Cladophora glomerata in the growth occurring appearing above 15 oC. Colorado River through Grand Canyon National Park. Cladophora and its highly branched filaments provide 156 large surface areas for the colonization of epiphytes and a refugium for invertebrates. Suspended sediment loads ABSTRACTS 59 delivered into the Colorado River via tributaries produce 159 variable turbidities along the Colorado River. Turbidity EXPERIMENTAL COMMERCIAL CULTIVA- changed from 0.5 NTU at Lees Ferry (Rkm 0.0) to 7.9 TION OF INDIGENOUS PORPHYRA SPECIES IN NTU at Gorilla Island (Rkm 352). We found that NORTHEAST AMERICA elevated sediment loads influenced cell morphology of Yarish, C.1, Wilkes, R.1, Chopin, T.2, Mathieson, C. glomerata along turbidity gradients. Primary A.C.3, & Lu, S.4 branches showed a significant decrease in cell lengths 1Department of Ecology & Evolutionary Biology, from 993 um (SE# 21) to 814 um (# 23) between the University of Connecticut, Stamford, CT 06901-2315 clear water habitat at Lees Ferry and the downstream USA; 2Centre for Coastal Studies and Aquaculture, turbid water habitat of Gorilla Island, while cell widths University of New Brunswick, Saint John, NB E2L 4L5 increased from 88 um (# 1.5) to 95 um (# 2). We Canada; 3Jackson Estuarine Laboratory, Adams Point, tested the effects of suspended sediments and light on University of New Hampshire, Durham, NH 03824 the cell morphology of C. glomerata in the field. USA; 4Experimental Marine Biology Laboratory, Cobbles colonized with C. glomerata were translocated Institute of Oceanology, Chinese Academy of Sciences, from Lees Ferry to a turbid water zone in the Paria Qingdao, P.R. China. River. Cells showed a significant decrease (30%) in length after one month. In contrast, in situ experiments We have embarked upon a study of domesticating in reduced light at Lees Ferry without suspended indigenous species of Porphyra for commercial sediments showed no significant changes in C. cultivation with the assistance of the New England and glomerata cell morphology. We propose that National Sea Grant College programs. Detailed modifications in cell dimensions strengthen filament seasonal and spatial collections, from diverse coastal and structure and reduce sheer stress in high-suspended estuarine habitats, have been made to delineate the sediment environments, reducing surface area for seasonality and habitat preferences of six species of epiphytic diatoms. The loss of surface area for Porphyra in coastal New England and the Canadian epiphytic growth may have important trophic Maritimes (Porphyra amplissima (Kjellman) Setchell & implications in the Colorado River foodweb. Hus in Hus, P. miniata (C. Agardh) C. Agardh, P. 158 umbilicalis (Linnaeus) J. Agardh, P. linearis Greville, RHODOLITH GROWTH FORMS AND SPECIES P. purpurea (Roth) C. Agardh, and P. leucosticta DISTRIBUTION IN THE GULF OF CALIFORNIA, Thuret in Le Jolis). At least four different species, P. MEXICO leucosticta, P. purpurea, P. amplissima and P. linearis, Yabur-Pacheco, R. & Riosmena-Rodriguez, R. are being examined for experimental commercial Herbario Ficologico, Dept. Biol. Mar., U.A.B.C.S., La production. Several strains of each of the species have Paz B.C.S. 23080 Mexico successfully completed their life cycles in culture and F2 individuals have been obtained for P. amplissima, P. Rhodolith beds in the Gulf of California are composed leucosticta and P. purpurea. Whether or not nori of three species and several growth-forms. We evaluated aquaculture will ultimately succeed in New England and the species and growth-form composition of rhodoliths the Canadian Maritimes will depend in large part upon in the two most common environments where beds several key factors, including: (1) successful transfer occur, shallow water areas influenced by primarily by and modification of Asian cultivation technologies to waves and deeper areas influenced by bioturbation and local coastal environments; (2) development of currents. Neogoniolithon trichotomun was restricted to genetically improved indigenous American cultivars of shallow beds in the central Gulf, while the other two marketable nori that will extend the growing and harvest species were widely distributed with Lithophyllum seasons; (3) establishing a constant supply of a margaritae dominant in deeper, sandy areas and "seedstock" of juvenile organisms that will be readily Lithothamnion crassiusculum dominant in shallow, available; (4) the expansion of the area presently used rocky areas. Fruticose growth forms were common for cultivation (i.e. beyond northern Maine) and (5) throughout the Gulf, but the presence and relative integrating nori mariculture with commercially abundance of other forms varied among sites. These important finfish aquaculture. results suggest that environmental factors such as depth and substrate greatly influence the structure and 160 distribution of rhodoliths in beds in this geographic ‘TASTE/ODOR METYABOLITE’-PRODUCING region. CYANOBACTERIA WITHIN CATFISH AQUACULTURE SYSTEMS: ABUNDANCE 60 ABSTRACTS

PATTERNS DURING THE SUMMER-FALL TRANSITION Zimba, P.1, Grimm, C.1, Lloyd, S.1, Weiriche, C.2, Fournie, J.3 & Millie, D.1 1U.S.D.A., Agricultural Research Service, New Orleans, LA 70124 USA; 2Louisiana Agricultural Experiment Station, Louisiana State University, Baton Rouge, LA 70803 USA; 3U.S. E.P.A., Environmental Research Laboratory, Gulf Breeze, FL 32561 USA

The presence of cyanobacteria in pond aquaculture systems can result in economic losses as a result of secondary metabolite formation. These compounds may include toxins as well as compounds that impart a noxious taste to fin and shellfish growing within these ponds. Fifteen channel catfish ponds were monitored weekly to assess algal composition, photo-pigment content (HPLC), and presence of off-flavor compounds (2-methylisoborneol-MIB and geosmin) during October- November 1997. Four of these ponds were also monitored for concentration of off-flavor in the fish population and on one occasion for intra-pond fish concentrations of MIB and microcystin. All ponds had filamentous blue-green taxa as dominants at the onset of sampling; coccoid cyanobacteria and diatoms replaced these as cooler weather approached. Pigment data also indicated a replacement of zeaxanthin-containing cyanobacteria with myxoxanthophyll-containing forms, as well as increased fucoxanthin (a diagnostic pigment for diatoms). Off-flavor concentrations in fish better coincided better with water concentrations of geosmin (r = 0.87) than MIB (r = 0.60) during this period. MIB in fish from one pond was highly variable, with coefficient of variation exceeding 30% of mean (n = 21). No evidence of microcystin damage was evident from liver analyses of these fish.

Top View