SCAMIT Newsletter Vol. 19 No. 12 2001 April
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April, 2001 SCAMIT Newsletter Vol. 19, No. 12 SUBJECT: No meeting in July; see below GUEST SPEAKER: DATE: TIME: LOCATION: Next Meeting: No meeting will be held in July. The August meeting is not yet finalized. Details will be announed in the May NL. Those whom this leaves with time on their hands can do a final sweep of their data for changes, or comments, additions to and eliminations from the SCAMIT species list. Send any modifications to Don Cadien at [email protected], call them in at 310-830- 2400x5502, or mail them to Don Cadien, Marine Biology Lab - JWPCP, 24501 S. Figueroa St., Carson, CA., 90745. ED. 4 Where is it? What in Hades is taking so long?!!! When will I have a copy to work with? All very good questions. Edition 4 of the SCAMIT listing of benthic invertebrates is still homing in on completion. It has been Lumbrineris nr limicola Hartman 1944 delayed by a number of factors, not the least of (posterior of animal with pygidium) which was the desire to incorporate all changes resulting from the Taxonomic Atlas series published by the Santa Barbara Museum of FUNDS FOR THIS PUBLICATION PROVIDED, IN PART BY THE ARCO FOUNDATION, CHEVRON, USA, AND TEXACO INC. SCAMIT Newsletter is not deemed to be valid publication for formal taxonomic purposes. April, 2001 SCAMIT Newsletter Vol. 19, No. 12 Natural History. The discussions resulting Living in Southern California we can from the last polychaete, and last series volume anticipate, if not predict, the onset of another (Volume 7), are being held on 11 June as the ENSO event in the near future. Having topic of that month’s SCAMIT meeting. This witnessed the influx of southern forms is the last input hurdle to be crossed. Once the associated with the last strong ENSO event, we conclusions (reached at the June meeting) can also anticipate and prepare for a similar regarding SCAMIT usage are available, Ed. 4 effect next time. The most obvious method of can be finalized. A number of members have doing so is to become more familiar with the contributed information concerning changes to southern fauna. The isopod fauna of the Ed. 3, and all deserve our thanks. Any other adjacent tropical eastern Pacific region is comments are still welcome and actively summarized by Espinosa-Pérez & Hendrickx solicited. Dale Calder, for instance, recently (2001). They document the southern range visited the Santa Barbara Museum and while limits of species whose distribution is there provided updates to the nomenclature predominantly temperate, as well as providing used in the Atlas Cnidaria volume. These were a comprehensive listing of the taxa found in forwarded by Eric Hochberg, and will be (usually) southern warm waters. Although incorporated into Ed. 4. Production will take some historic records are viewed as incorrect some weeks, but availability of the new edition (and corrections provided for these erroneous is expected in August. Thanks for the patience accounts) 124 isopod species were viewed as you have already exhibited, and (in advance) occurring within the coverage area. The for its continuation. Please avail yourself, comprehensive bibliography also alerts us to within the next few weeks, of the opportunity numerous sources in the Mexican literature of to finalize and submit all changes which should which we may not have been familiar. be included in this new edition . Aspects of the ecology of several local decapod NEW LITERATURE species are examined by Dugan et al (2000). Three burrowing hippid crabs are compared Earlier newsletters have introduced several with respect to their ability to burrow, and their papers dealing with the utility of nematocysts behavior in response to intertidal water motion. in cnidarian classification. Östman (2000) The authors found that while burrowing speed revisits this territory and provides an update to in the sand crab Emerita analoga was not the nomenclature of nematocysts. A collection significantly affected by sediment type, that of of images gleaned from both light microscopes the mole crab Lepidopa californica and the and scanning electron microscopes are used to spiny mole crab Blepharipoda occidentalis was illustrate the types of nematocysts and the (it was reduced in coarse sediments). Their terms which describe them. Although few consequent habitat restriction to fine sands SCAMIT members routinely investigate the seems to support the “swash exclusion cnidom of cnidarians they seek to identify, it hypothesis” and limits the latter two species remains a useful (sometimes necessary) almost entirely to subtidal occurrence. addition to other morphological characters. The relative value of “hard” (read shell and In a paper dealing with several mysid species radula) vs. “soft” (read anatomy of tissues and Fukuoka and Murano (2001) place organs) characters in both mollusk phenetic Acanthomysis brunnea in the synonymy of and phylogenetic analyses has long been a Columbiaemysis ignota. Since A. brunnea was source of debate. As with any group fairly recently described by Murano & Chess possessing hard parts and, in consequence, a we can be sure this synonymy was not lengthy fossil record, there are always suggested lightly. proponents of the idea that only hard structures 2 April, 2001 SCAMIT Newsletter Vol. 19, No. 12 can be used if data from extinct taxa is to be morphological and physiological variations included. Such direct evidence of the path of observed over the species’ range. They found evolution within the group is highly valued. homogenous gene structure within each variant Others contend that local forces act primarily color pattern within each population, and on the shell, and that shell features of taxa from variations between the same variant in distant different lineages tend to converge within populations. Resolution of this taxon into a habitat. This faction would minimize or complex of closely related species remains a eliminate hard part evidence, despite the possibility under investigation. sacrifice of most of the fossil record, to avoid homoplasy noise introduced by convergent Multivariate analyses typically exclude that shell structure. A number of authors have portion of the fauna which occurs only straddled this ideological fence and used data infrequently and/or at very low density. While from all available sources. Schander and the basis of this is generally that such small Sundberg (2001) weigh in with a new analysis signals cannot be distinguished statistically examining a series of such studies using both from background noise, the unfortunate result hard and soft characters. Within each study the is exclusion of virtually all rare species from consistency and retention indices were analysis. This is repugnant not only on the calculated and compared for the two types of philosophical basis of viewing the most characters. They found no statistical evidence inclusive analysis as best representing the that homoplasy was greater in the shell than in community, but also because rare species have the tissue characters used. They did point out unique characteristics. While rarity is not a that obviously homoplastic shell characters simple issue, it is often assumed that most rare may have been rejected by the authors before species either require specialized habitats of analysis was undertaken. If we assume the 28 limited availability (are stenotopic) or are less studies examined are fairly typical, there does able to survive in suboptimal environments, not appear to be a sufficient rationale, on the such as those impacted by man (are sensitive). basis of homoplasy, to ignore shell characters Their elimination skews perceptions of the in the phyletic analysis of mollusks. community by only considering eurytopic species tolerant of perturbed and suboptimal Rouse (2000) revisits evidence from larval habitats. This renders determinations of feeding and its effect on phyletic analyses of similarity between sites adjacent to and distant metazoan relationships. His reconsideration from anthropogenic inputs suspect, or at least points not to plesiomorphy of down-stream less persuasive. There is evidence that when larval feeding, but rather repeated origination rarity results not from any character of the and loss. He concludes that it is more taxon concerned, but from competitive defensible to hypothesize lecithotrophy as the exclusion by other species, most rare species plesiomorphic larval nutritive mode in the populations increase in response to disturbance Spiralia. Read the paper and see if you concur. of the competitive balance (Hawkins et al 2000). Research on the small and widely distributed ophiuroid Amphipholis squamata has been Cao et al (2001) review the rare species intensive in recent years. Deheyn has situation in multivariate analyses conducted published many reports discussing with newer analytic tools and procedures. They bioluminescence and variations in color and suggest that the theoretical justification for color pattern within and between distant ignoring rare species is weak, and that populations of the species (see meeting adjustments to sample size and analytical minutes concerning his presentation). Dupont procedure can facilitate their inclusion in et al (2000) test the link between genetic and 3 April, 2001 SCAMIT Newsletter Vol. 19, No. 12 analysis. Although viewed from a freshwater and consistency of the data. Our previous perspective, the authors’ comments should be experience with the 1994 Bight Pilot Project considered by those using multivariate lumbrinerid identifications showed that in methods on marine benthic community data. many cases we had to regress from species level to generic level due to identification MINUTES OF APRIL 9 MEETING inconsistencies between labs. The meeting was held at the Scripps Larry presented a chart showing the species Insititution of Oceanography. President Ron names, sum of abundances, and number of Velarde opened the business portion of the occurrences for each of the species. No meeting. The Coastal Zone 2001 conference specimens of Lumbrineris index were recorded will be held in Cleveland, Ohio on July 15 for the Bight’98 project. He commented on a through 19, 2001.