Vol. 14(1) 2003 March

Total Page:16

File Type:pdf, Size:1020Kb

Vol. 14(1) 2003 March New York Flora Association - New York State Museum Institute Steve Young and Laura Lehtonen, Editors Correspondence and dues to NYFA, 3140 CEC, Albany, NY 12230 Join $15 - Dues $10/Yr Vol. 14 No. 1 March, 2003 e-mail: [email protected] website: www.nyflora.org NYFA Resumes Small Grants $$$ NYFA 2003 The New York Flora Association is again In the past, NYFA grants have funded a study Field Trips See Page 8 for more details! soliciting proposals for small grants to foster of the West Hills County Park in Suffolk field botany in New York State. It is estimated County (Greller and Clemants, NYFA • May 24 Bryophtye that we will have about $1,500-$2,000 newsletter, Aug, '94); a study of the flora of Workshop, Adirondack old available for grants. Below are some examples French Creek Drainage (Douglas Goldman, growth forests of the kinds of projects that NYFA would like NYFA Newsletter, June, '96); and software to to fund: develop herbarium labels for the the New York • June 14 Joralemon Woods, Natural Heritage Program. Albany Co. - Botanical studies of rare plant communities In addition, NYFA has funded portions of • June 28 Spring Pond Bog, or unusual community types such as the inland the on-line flora atlas and the NYFA website. Franklin Co. salt marshes near Syracuse. Applicants should be either NYFA - Botanical surveys of under-studied or under- members or students. Proposals should be less • August 9 Altona Flat Rock surveyed areas of the state that are likely to than five pages long and include: a needs and Gadway Sandstone Pave- produce many new county records statement, methods to be used, a schedule, a ment Barrens, Clinton Co. - Field research of under-studied groups such budget, statement of goals, expected products • September 6 Hudson High- as lichens or liverworts of research, and resume of the applicant(s). lands including Round Hill & - Studies of specific taxa Grants will be in the $200-$1,000 range, and Moodna Creek, Orange Co. - Field trips, workshops, or other educational can cover equipment, travel expenses, etc. but activities cannot be used to for salaries. Award winners - Invasive plant studies are expected to write a report for publication in - Development of botanical tools or software the NYFA Newsletter and deposit high quality - Herbarium research on New York State flora specimens in a public herbarium. Email proposals are preferred. Proposals or questions should be sent to [email protected]. Rediscovery of Spiny Naiad Inside this issue: (Najas marina L.) in New York A new botany magazine 3 Joseph M. McMullen - Terrestrial Environmental Specialists, Inc., Phoenix, NY Spiny naiad (Najas marina L.) is a state-listed dicated in the thorough account of the species Eleocharis aestuum in NY 4 endangered species previously only of histori- by Stuckey (1985), it has a rather odd distribu- cal record in New York. During the summer tion and is frequently local. He reports it as Theo plant label maker 7 of 2002 a large colony of Najas marina distributed locally across the Great Lakes re- (Najadaceae) was discovered by the authors at gion from New York to Wisconsin and further NY Plants - NY People 8 the Montezuma National Wildlife Refuge west in Minnesota and the Dakotas; and in the (MNWR) in the Town of Tyre, Seneca Gulf Coast areas in Texas and Florida; the Field trip schedule 8 County. Details of that find and a historical West Indies and southwest to Mexico and perspective of the species are provided in this Central America. New on the NYFA net 9 article. Najas marina is an annual, sub- The last verified record of Najas ma- Test your plant knowledge 9 merged, rooted aquatic vascular plant. As in- rina in New York (see more on page two) NYFA March 2003 Page 1 was a 1948 Cayuga County collection of Clausen (NYNHP species in the eastern United States, north of Florida. There are data). It was historically known from Onondaga, Cayuga, Se- some potentially valid reports of the species unsubstantiated by neca, Wayne, and Monroe counties in the central portion of the voucher specimens. These include the report from the MNWR, state (NYFA 1990). These historical populations represent the Seneca County by Cowardin (1965), and potential findings by northeastern extent of the species in North America. It occurs in Rawinski from the northern end of Cayuga Lake (Stuckey 1985). no other state in the northeast U.S. No other recent records or reports are known for the state. Najas marina was first discovered in New York in Although the NYNHP’s last reported record was that of 1864 growing in Onondaga Lake by Judge George W. Clinton Clausen, a September 15, 1981 collection was made by Tom (son of Governor DeWitt Clinton and one of the first State Bota- Rawinski in Cayuga Lake, across from Canoga Marshes, Seneca nists). Clinton’s original citation is as follows: “Naias major, Falls, Seneca County. This collection went unnoticed by the Allioni. In the Onondaga Lake, and in the mouth of a stream NYNHP because the specimens were not deposited in a New and pools on the beach of the lake at York herbarium, although they were Liverpool, Onondaga County, Septem- deposited at the Gray Herbarium (T. ber 1864. G.W.C” (Clinton 1865). Weldy, pers. com.). His records and other original distribu- tional history information for New From a habitat standpoint, Na- York are discussed in Fernald (1923). jas marina is a species traditionally known from brackish, saline, subsaline, The Rev. John Paine quickly or alkaline waters of ponds, lakes, and added additional records in Onondaga marshes (Stuckey 1985, Crow and Lake. In Paine (1865), he states Hellquist 2000, Haynes 2000). Faust “Naias major, Allioni. Borders of and Roberts (1983) report that it oc- Onondaga Lake. Discovered by G. W. curred in central New York in saline Clinton, in October 1864, growing in portions of Onondaga Lake and marshes a stream emptying into the lake near in association with several halophytic Liverpool. It abounds, however, in the species. lake in water ten to twenty-five feet deep; most luxuriantly along the edge Water depths reported for Najas of a sudden descent of the bottom, at a marina populations varies. Paine (1865) distance from shore.” He further ref- noted it abounding in Onondaga Lake in erences a few locations from Florida ten to twenty feet of water. However, and states “The above habitats, with our more recent records are from shal- our own are the only stations of this low, quiet water, usually 2 to 3 feet in plant known on the American conti- depth. Substrate types are reported to be nent.” muddy or sandy. From these initial New York The currently discovered popu- findings, there were a series of addi- lation from the MNWR, Seneca County tions to the distributional record in the may be from the same area originally late 1800s and early 1900s. These reported by Dudley (1886), and the more findings were mostly from the north- recent report of Cowardin (1965). This ern portion of the Finger Lakes region large population was found growing in and the area around Rochester. Loca- shallow, quiet water on a substrate of tions include: Irondequoit Bay, Monroe County (originally in muck. Summer water depth was 0.4 to 0.6 meters. The species 1865 by Booth (as reported by Fernald 1923), and later by occurred in a dense aquatic bed; which included associated spe- Beckwith and McCauley 1896, and Beckwith et al. 1917); Se- cies of coontail (Ceratophyllum demersum), sago pondweed neca River near Savannah, Wayne County (Peck 1874); Black (Coleogeton pectinatum), bladderwort (Utricularia vulgaris), Lake and foot of Cayuga Lake, Cayuga and Seneca? counties duckweed (Lemna minor and L. trisulca), and milfoil (Dudley 1886); Tully Lake, Onondaga County (an 1895 report in (Myriophyllum sp.). Goodrich 1912); Canoga marshes, Duck Lake, and Crusoe Lake, Cayuga County (Weigand and Eames 1926); Mendon Ponds, Najas marina is obviously a rare species of sporadic Monroe County (Clausen 1940); and eventually Clausen’s 1948 distribution in the northeastern United States. Its habitat require- record from Cayuga County. ments likely include a narrow range of conditions that may be negatively influenced by man’s manipulation. Saline, subsaline, As noted by Stuckey (1985), the recent records of the and alkaline habitats in areas of limited disturbance where his- species in New York are scarce. Between 1923 and 1936, torical populations occurred should be further searched for this Clausen (1936) reports that no new findings were made for the interesting aquatic species. NYFA March 2003 Page 2 References House, Homer D. 1924. Annotated list of the ferns and flower- ing plants of New York State. New York State Mu- Beckwith, Florence and Mary E. McCauley. 1894. Plants of seum Bulletin No. 254, Albany, NY. 759 pp. Monroe County, New York, and adjacent territory. Proc. Rochester Academy Science 3: 1-150. Muenscher, W. C. 1928. Vegetation of Cayuga and Seneca Lakes. pp. 243-248, list pp. 246-248. In A biological Beckwith, Florence and Mary E. McCauley and Milton S. Bax- survey of the Oswego River system supplemental to ter. 1917. Plants of Monroe County, New York, and seventeenth annual report 1927. Conservation Depart- adjacent territory. Second Supplementary List. Proc. ment, State of New York, Biological Survey No. 2 Rochester Academy Science 5: 59-121. (1927). Albany, NY. 248 pp. Clausen, Robert T. 1936. Studies in the genus Najas in the NYFA. 1990. Atlas of New York State Flora. New York Flora northern United States. Rhodora 38: 333-345. Association. New York State Museum Institute, Al- bany, NY. 496 pp. Clausen, Robert T. 1940. Aquatic vegetation of the Lake On- tario watershed.
Recommended publications
  • 27April12acquatic Plants
    International Plant Protection Convention Protecting the world’s plant resources from pests 01 2012 ENG Aquatic plants their uses and risks Implementation Review and Support System Support and Review Implementation A review of the global status of aquatic plants Aquatic plants their uses and risks A review of the global status of aquatic plants Ryan M. Wersal, Ph.D. & John D. Madsen, Ph.D. i The designations employed and the presentation of material in this information product do not imply the expression of any opinion whatsoever on the part of the Food and Agriculture Organization of the United Nations (FAO) concerning the legal or development status of any country, territory, city or area or of its authorities, or concerning the delimitation of its frontiers or boundaries. The mention of speciic companies or products of manufacturers, whether or not these have been patented, does not imply that these have been endorsed or recommended by FAO in preference to others of a similar nature that are not mentioned.All rights reserved. FAO encourages reproduction and dissemination of material in this information product. Non-commercial uses will be authorized free of charge, upon request. Reproduction for resale or other commercial purposes, including educational purposes, may incur fees. Applications for permission to reproduce or disseminate FAO copyright materials, and all queries concerning rights and licences, should be addressed by e-mail to [email protected] or to the Chief, Publishing Policy and Support Branch, Ofice of Knowledge Exchange,
    [Show full text]
  • Najas Guadalupensis (Spreng.) Magnus; Najas Southern Naiad Marina Najas Marina L.; Hollyleaf Naiad Naiads
    A WEED REPORT from the book Weed Control in Natural Areas in the Western United States This WEED REPORT does not constitute a formal recommendation. When using herbicides always read the label, and when in doubt consult your farm advisor or county agent. This WEED REPORT is an excerpt from the book Weed Control in Natural Areas in the Western United States and is available wholesale through the UC Weed Research & Information Center (wric.ucdavis.edu) or retail through the Western Society of Weed Science (wsweedscience.org) or the California Invasive Species Council (cal-ipc.org). Najas guadalupensis (Spreng.) Magnus; Najas southern naiad marina Najas marina L.; hollyleaf naiad Naiads Family: Hydrocharitaceae or Najadaceae Range: Southern naiad is found throughout the United States. Hollyleaf naiad is found in California, Arizona, Nevada, Utah and New Mexico. Habitat: Southern naiad inhabits still or slow-moving water in a broad range of substrates, including ponds, Najas lakes, reservoirs, canals, rice fields, and irrigation ditches. Grows at water depths of 3 to 15 ft and tolerates polluted guadalupensis water or slightly brackish water. Hollyleaf naiad inhabits fresh to brackish water marshes, ponds, lakes, slow-moving streams, canals, and irrigation systems Origin: Southern naiad is a common widespread native of North and South America. Hollyleaf naiad is native to the southwestern United States. Impacts: Both naiads are usually not considered weedy in natural habitats. The foliage and seeds are an important food source for wildlife, especially shorebirds and waterfowl. However, they can become troublesome in ditches, human-made ponds, and disturbed or controlled aquatic systems where populations can become locally dominant, forming dense submersed mats of vegetation.
    [Show full text]
  • Taxonomy Monocots
    Taxonomy Monocots- 1. Typhaceae - commonly called the Cattail Family (aceae ending means family). These are emergent, rhizomatons, found in fresh or brackish waters. • Typha (genus) domingensis (species): This is the species found in AZ. • Typha latifolia 2. Potamogetonaceae - the Pondweed Family. This family is rooted and submerged. • Potamogeton: commonly known as Pondweeds; many species are found. • Ruppia: commonly known as Widgeon grass; found in fresh or brackish waters. • Zannichelia: commonly known as Horned Pondweed; found in fresh or brackish waters. • Zoestra: marine seagrass. • Halodule: marine seagrass. • Cymodocea: marine seagrass. • Phyllospadix: marine seagrass. 3. Najadaceae - the Niad Family. This family is also rooted and submerged; there is only one genus. • Najas marina: commonly known as the spiny niad; found in brackish waters. Typically known as a problem plant because it grows course and very quickly. 4. Hydrocharitaceae - the Frogbit Family. This family is rooted and submerged, and is found in fresh and marine waters. • Anacharis densa: commonly known as Waterweed, also called Elodea. A very common aquarium plant, considered a problem plant in freshwater lakes. • Halophila: found in marine habitats. • Thalassia: commonly known as Turtlegrass (another type of seagrass); found in marine habitats. • Vallisneria: commonly known as Wild Celery, a common food for ducks and other water fowl; found in freshwater. 5. Graminaceae (Poaceae)- the Grass Family. Grasses can be identified by the swollen base of each leaf where it meets the stem. This is called a ligule. There are 22 genera, important ones are listed. Most of these are emergent and rooted. • Phragmites australis: commonly known as the Giant Reed, similar to Arundo; found in freshwater.
    [Show full text]
  • Changes in the Marsh and Aquatic Vascular Flora of East Harbor State Park, Ottawa County, Ohio, Since 18951
    CHANGES IN THE MARSH AND AQUATIC VASCULAR FLORA OF EAST HARBOR STATE PARK, OTTAWA COUNTY, OHIO, SINCE 18951 DAVID L. MOORE, Department of Botany, The Ohio State University, Columbus, Ohio 43210 Abstract. Numerous changes in the marsh and aquatic flora of East Harbor State Park have occurred since 1895. Of the 89 species collected and identified before 1900, 22 are no longer present. This represents a loss of approximately 25% of the species originally reported by Moseley (1899) and Pieters (1901). The species lost would rise to 42%, if those species formerly abundant, but now rare, or occurring as one or two small, isolated populations disappear. Probable causes for these changes are wind and water erosion, fluctuating water levels, dredging, establishment and spread of species new to the park, and increase or decrease in abundance of species already present. OHIO J. SCI. 76(2): 78, 1976. Since it was purchased in 1946 as a These sites were visited at two week intervals from June to August 1972, with additional col- site for an outdoor recreational facility, lections in April, May, September, and October. East Harbor State Park has undergone Plant specimens representing all the vascular both natural and artificial changes. The taxa present were collected by traversing the park is located on the south shore of Lake study sites on foot in paths parallel to the shore- line of both Middle and East Harbor, until the Erie, 81 miles west of Cleveland and 45 entire study site had been covered. The water miles east of Toledo, near Sandusky, at surfaces of study sites III, IV, V, and VI were the junction of State Routes 163 and 269 surveyed by canoe.
    [Show full text]
  • Re-Establishment Plan for the Natura 2000 Species Najas Flexilis in Poland
    Re-Establishment Plan for the Natura 2000 Species Najas flexilis in Poland Final Version, 02-17-2005 Coordination: Emmanuel Thiry Ministry of Environment – DOP, Wawelska Street 52-54, 00-922 Warsaw, Poland Dr. Klaus van de Weyer Ulrich W. Abts (sediment) lanaplan, Lobbericher Str. 5, D-41334 Nettetal, Germany tel +49-2153-97 19 20 fax +49-2153-97 19 21 e-mail: [email protected] www.lanaplan.de 1 Introduction .......................................................................................................1 2 Methods ..............................................................................................................2 3 Distribution of Najas flexilis in Poland............................................................3 4 Biology and Ecology of Najas flexilis...............................................................4 5 The Study Sites ..................................................................................................5 5.1 Binowskie Lake..........................................................................................................................5 5.1.1 Aquatic Macrophytes ......................................................................................................5 5.1.2 Sediment Samples ...........................................................................................................7 5.2 Glinna Lake................................................................................................................................7 5.2.1 Aquatic Macrophytes ......................................................................................................7
    [Show full text]
  • Using Paleoecology to Investigate the Decline of Najas Flexilis (A Rare Aquatic Plant)
    Accepted: 15 May 2019 DOI: 10.1002/geo2.81 RESEARCH ARTICLE Filling the “data gap”: Using paleoecology to investigate the decline of Najas flexilis (a rare aquatic plant) Isabel J. Bishop | Helen Bennion | Carl D. Sayer | Ian R. Patmore | Handong Yang Environmental Change Research Centre, In the absence of long‐term monitoring records, paleoecology can be used to University College London, London, UK extend knowledge of species and community ecology into the past. The rare and Correspondence declining aquatic plant Najas flexilis is a priority species for conservation across Helen Bennion Email: [email protected] Europe, and is an ideal candidate for paleoecological study; not only are historical records of the plant sparse, but its seeds are commonly found and well preserved Funding information in lake sediment cores. In this study, we investigate the timing and causes of Scottish Natural Heritage/Scottish Environmental Protection Agency, Grant/ decline at two UK sites at which N. flexilis has recently become extinct: Esth- Award Number: 41040‐PP491 waite Water (England) and Loch of Craiglush (Scotland). For both sites, multiple paleoecological indicators and available historical biological records and monitor- ing data are compared to numbers of N. flexilis seeds enumerated in dated sedi- ment cores representing the last 150 years. At Esthwaite Water, N. flexilis seeds were found in abundance in association with indicators of a clear, oligo‐me- sotrophic, mildly alkaline lake. Eutrophication led to the disappearance of N. flex- ilis in the 1980s. By contrast, far fewer N. flexilis seeds were found in a core from Loch of Craiglush, and the current period of N.
    [Show full text]
  • Environmental Drivers for the Distribution of Najas Marina L
    Egyptian Journal of Aquatic Biology & Fisheries Zoology Department, Faculty of Science, Ain Shams University, Cairo, Egypt. ISSN 1110 – 6131 Vol. 24(7): 741 – 755 (2020) www.ejabf.journals.ekb.eg Environmental drivers for the distribution of Najas marina L. subsp. armata in Lake Burullus, Egypt Khalid M. Yousif, Maha M. Elshamy, Ghada A. El-Sherbeny* Botany Department, Faculty of Science, Mansoura University, Mansoura 35516, Egypt *Corresponding author: [email protected] ______________________________________________________________________________ ARTICLE INFO ABSTRACT Article History: Najas marina L. subsp. armata (Lindb.f.) Horn, family Najadaceae, Received: Oct. 30, 2020 which called Horreish in Egypt, is a submerged aquatic plant, inhabits fresh or Accepted: Nov. 29, 2020 brackish water. The plant collected from Nasser Lake (Egypt), dried, and kept to Online: Dec. 7, 2020 be used later as a vital source of fodder for sheep and goats in dry periods as it is _______________ offered in local markets as food in Hawaii. This work is the first study on N. marina in the Nile Delta of Egypt as the global studies were rare and outdated. Keywords: The ultimate goal of this work is to specify the environmental agents (water and Najas marina; sediment) controlling the N. marina distribution in Lake Burullus, identify the Salinity; plant communities associated with N. marina, and assess the plants- Nutrients; environmental agents' relationship. Results obtained by Canonical CCA; Correspondence Analysis (CCA) indicated that the major efficacious Environment environmental agents (water and sediment) that affect the distribution of N. - - marina in Lake Burullus, were salinity factors as, EC, TDS, Cl , HCO3 and some elements as Na+ and Mg++ as well as nutrients (TN and TP).
    [Show full text]
  • HYDROCHARITACEAE 1. NAJAS Linnaeus, Sp. Pl. 2: 1015. 1753
    HYDROCHARITACEAE 水鳖科 shui bie ke Wang Qingfeng (王青锋)1, Guo Youhao (郭友好)2; Robert R. Haynes3, C. Barre Hellquist4 Herbs, annual or perennial, submerged or floating, aquatic, in fresh or brackish water or marine. Stems short or elongated, sometimes stoloniferous. Leaves radical or cauline, alternate, opposite, subopposite, whorled, or pseudowhorled, sessile or petiolate, usually sheathing at base. Flowers unisexual or bisexual, actinomorphic, enclosed in a bifid spathe or within 2 opposite spathal bracts, or rarely not spatulate; spathes sessile or pedunculate. Stamens 1 to many, occasionally some staminodal; anthers 1–4- thecous. Ovary inferior, 1-loculed; carpels 2–15, fused; ovules few to many, on parietal, sometimes intruding placentae; styles 2–5; stigmas usually bifid. Fruit a fleshy and berrylike capsule dehiscent or opening by decay of pericarp, or an achene (Najas). Seeds numerous, usually small, without endosperm; embryo straight. Eighteen genera and ca. 120 species: widely distributed in tropical and subtropical regions of the world; 11 genera (one introduced) and 34 species (four endemic, one introduced) in China. Wang Huiqin & Sun Xiangzhong. 1992. Hydrocharitaceae. In: Sun Xiangzhong, ed., Fl. Reipubl. Popularis Sin. 8: 151–190; Zhou Lingyun, You Jun & Zhong Xiongwen. 1992. Najas. In: Sun Xiangzhong, ed., Fl. Reipubl. Popularis Sin. 8: 108–125. 1a. Fruit an elliptic-oblong achene; perianth 2-lipped; plant annual, submerged in fresh or brackish water; leaves sessile ...... 1. Najas 1b. Fruit a fleshy and berrylike capsule; perianth segments free, 1- or 2-seriate, 3 per series, outer often sepaloid, inner petaloid; plant perennial or annual, floating or submerged; leaves petiolate or sessile. 2a.
    [Show full text]
  • Aquatic Plant Brittle/Lesser/Bushy/Slender/Spiny/Minor Naiad; Waternymph I
    Aquatic Plant Brittle/Lesser/Bushy/Slender/Spiny/Minor Naiad; Waternymph I. Current Status and Distribution Najas minor a. Range Global/Continental Wisconsin Native Range Europe, Asia, Turkey, Japan, India, Northern Africa1 Figure 1: U.S and Canada Distribution Map2 Figure 2: WI Distribution Map Abundance/Range Widespread: Eastern United States3,4 Not widespread Locally Abundant: Southeastern United States5 Rock Co., Adams Co. Sparse: Not often reported as a problem in the Unknown United States5 Range Expansion Date Introduced: Hudson River, 19346,7 First discovered in Rock Co., August 2007 Rate of Spread: Slow in Massachusetts6; rapid in Unknown southeastern and mid-Atlantic states5 Density Risk of Monoculture: Medium to high2,7 Unknown Facilitated By: Eutrophic conditions3 Unknown b. Habitat Lakes, ponds, reservoirs, slow-moving streams, canals7 Tolerance Chart of tolerances: Increasingly dark color indicates increasingly optimal range1,2,8,9 Preferences More tolerant of turbidity and eutrophic conditions6,7; alkaline waters streams, ponds, and lakes8; reports of growth up to 5 meters deep10; sand or gravel substrate10 Page 1 of 4 Wisconsin Department of Natural Resources – Aquatic Invasive Species Literature Review c. Regulation Noxious/Regulated2: AL, CT, MA, ME, SC, WA Minnesota Regulations: Prohibited; One may not possess, import, purchase, propagate, or transport Michigan Regulations: Not regulated Washington Regulations: Not regulated II. Establishment Potential and Life History Traits a. Life History Submersed, aquatic, monoecious annual herb6 Fecundity High4 Reproduction Sexual; Asexual7 Importance of Seeds: Primary means of reproduction; seed set is prolific4,7 Vegetative: Yes; species fragments very easily; fragments may also carry seeds5,7 Hybridization Undocumented Overwintering Winter Tolerance: Reported low winter tolerance; 8°C (47°F) minimum temperature2 Phenology: Seed germination occurs in early spring5 b.
    [Show full text]
  • 1. NAJAS Linnaeus, Sp. Pl. 2: 1015. 1753. 茨藻属 Ci Zao Shu Herbs, Annual, Small, Submerged in Fresh Or Brackish Water
    Fl. China 23: 91–95. 2010. 1. NAJAS Linnaeus, Sp. Pl. 2: 1015. 1753. 茨藻属 ci zao shu Herbs, annual, small, submerged in fresh or brackish water. Stem slender, fragile, much branched, rooting at base and lower- most nodes. Leaves subopposite or pseudowhorled, sessile, linear, small, 1-veined, sheathing at base, margin spinulose-toothed; sheaths variously shaped, often auriculate. Plants monoecious or dioecious; flowers minute, unisexual, solitary or few in leaf axil. Male flowers spatulate or rarely not spatulate; perianth (often named “involucre” or “envelope”) 2-lipped, membranous, closely applied to anther; stamen 1, anther subsessile, 1–4-thecous, dehiscing at apex. Female flowers sessile; spathe absent or rarely present; perianth persistent. Fruit an elliptic-oblong achene; pericarp thin, membranous, indehiscent, persistent. Seeds without endosperm; testa hard, brittle, pitted; embryo straight. About 40 species: cosmopolitan; eleven species (one endemic) in China. One of the Fl. China editorial committee, Wu Zhengyi, prefers to keep the Najadaceae separate because of its distinct morphology in having superior ovaries and nuclear endosperms. 1a. Plants dioecious; stems and abaxial surface of leaves usually spiny; areoles on seeds irregularly arranged ................. 1. N. marina 1b. Plants monoecious; stems and abaxial surface of leaves usually not spiny; areoles on seeds longitudinally arranged. 2a. Anthers 1-thecous. 3a. Seeds with many transversely elongated ladderlike pits; areoles fusiform; fruit narrowed and slightly curved at apex ........................................................................................................................................................ 2. N. minor 3b. Seeds with many longitudinally elongated pits; areoles rectangular or polygonal; fruit usually straight. 4a. Auricles broadly triangular; leaves in pseudowhorls of 3 ..................................................................... 5. N. browniana 4b. Auricles orbicular or obcordate; leaves in pseudowhorls of 5.
    [Show full text]
  • Taxonomic Notes on the Genus Najas (Hydrocharitaceae) in Thailand: Addition of N
    THAI FOREST BULL., BOT. 44(2): 104–107. 2016. DOI: 10.20531/TFB.2016.44.2.03 Taxonomic notes on the genus Najas (Hydrocharitaceae) in Thailand: addition of N. major and exclusion of N. minor YU ITO1 ABSTRACT The genus Najas (Hydrocharitaceae) was treated for the Flora of Thailand in 2001 with four species recorded. Through field and herbarium observations, it is proposed to exclude one of these four species, N. minor. A further species, N. marina, is reported for the first time. An updated key to the species is provided. KEYWORDS: aquatic monocots, Hydrocharitaceae, Najas L., taxonomy, Thailand. Published online: 2 December 2016 INTRODUCTION “Najas minor All.” by Haynes in 1985 was found in BKF herbarium (SN076057; Fig. 1A). This specimen, The floristic treatment for the genusNajas L. however, exhibits neither of the diagnostic characters (Hydrocharitaceae) was published as one of the eight of N. minor and instead has non-recurved leaves and genera of Hydrocharitaceae in Thailand (Haynes, hexagonal areolae (Fig. 1A, B). With its sloping leaf 2001). The following four species were included: sheath (Fig. 1C), the specimen is within the circum- Najas graminea Delile var. graminea, N. kingii scription of N. kingii in the key to the species in Rendle, N. malesiana W.J. de Wilde, and N. minor Haynes (2001), as it was annotated by L. Triest in 1991 All. Among them N. minor is of particular interest (Fig. 1A). Ito & Barfod (2014), in their preliminary because this species is mainly distributed in cool- checklist of aquatic plants of Myanmar and Thailand, temperate regions in the Northern hemisphere, and treated this specimen under the wider concept of N.
    [Show full text]
  • Assessing the Invasive Potential of Najas Minor in Maine
    Colby College Digital Commons @ Colby Honors Theses Student Research 2019 Assessing the Invasive Potential of Najas minor in Maine Kaitlin M. Volk Colby College Follow this and additional works at: https://digitalcommons.colby.edu/honorstheses Part of the Natural Resources Management and Policy Commons Colby College theses are protected by copyright. They may be viewed or downloaded from this site for the purposes of research and scholarship. Reproduction or distribution for commercial purposes is prohibited without written permission of the author. Recommended Citation Volk, Kaitlin M., "Assessing the Invasive Potential of Najas minor in Maine" (2019). Honors Theses. Paper 925. https://digitalcommons.colby.edu/honorstheses/925 This Honors Thesis (Open Access) is brought to you for free and open access by the Student Research at Digital Commons @ Colby. It has been accepted for inclusion in Honors Theses by an authorized administrator of Digital Commons @ Colby. Assessing the Invasive Potential of Najas minor in Maine An Honors Thesis Presented to The Faculty of The Department of Biology Colby College in partial fulfillment of the requirements for the Degree of Bachelor of Arts with Honors by Kaitlin Volk Waterville, ME May 18, 2019 Advisor: Catherine Bevier _______________________________________ Reader: Chris Moore ________________________________________ Reader: Judy Stone ________________________________________ Abstract Najas minor (European naiad), a relatively new invasive aquatic plant to the state of Maine, is thought be spreading more aggressively than previous invasive aquatic plants have. Once established, N. minor grows into dense monocultures that replace all native plant species, leading to a disruption in ecosystem functioning, a loss in food and habitat for invertebrates and fish, and a decrease in the recreational value of a waterbody.
    [Show full text]