1. Family: Araceae Juss.
    1. Lemna L.

      1. This genus is accepted, and its native range is Cosmopolitan.

    [FTEA]

    Lemnaceae, F. N. Hepper. Flora of Tropical East Africa. 1973

    Habit
    Aquatics, submerged or more usually floating in great numbers; individual thalli cohering
    Thallus
    Daughter thallus budding from lateral pocket Thalli oblong to ovate, ± asymmetrical, thin or spongy
    Roots
    Root solitary, devoid of hairs,shortly sheathed near point of origin; sheath simple or laterally winged; apex of root sheathed by a conspicuous root-cap, tip acute or obtuse
    Flowers
    Flowering erratic; floral pocket lateral with spathe enclosing 2 staminate and 1 pistillate flowers
    Fruits
    Fruit (l–6)-seeded
    Seeds
    Seed usually ribbed.
    [CATE]

    CATE Araceae, 17 Dec 2011. araceae.e-monocot.org

    General Description
    Fronds with 1 - 5 (7) veins and 1 to several layers of air spaces and raphides; pigment cells lacking; fronds not surrounded by a prophyll; 1 root per frond; pistil with 1 amphitrophous or atropous or 2 - 7 anatropous ovules; seeds 0.4 - 0.9 mm long, with 8-60 longitudinal ribs.
    Distribution
    Cosmopolitan.
    Diagnostic
    Free floating aquatic plants reduced to small, leaf-like, poorly differentiated fronds; roots and veins present; lack calcium oxalate druses. Differs from Spirodela in having only 1 root per frond, 1-5 veins (rarely 7 in Lemna gibba ) and the base of the frond lacking a scale.

    Images

    Distribution

    Native to:

    Afghanistan, Alabama, Alaska, Albania, Alberta, Aldabra, Algeria, Altay, Amur, Angola, Argentina Northeast, Argentina Northwest, Argentina South, Arizona, Arkansas, Aruba, Austria, Azores, Bahamas, Baleares, Baltic States, Bangladesh, Belarus, Belgium, Belize, Benin, Bermuda, Bolivia, Borneo, Botswana, Brazil North, Brazil Northeast, Brazil South, Brazil Southeast, Brazil West-Central, British Columbia, Bulgaria, Burkina, Burundi, Buryatiya, Cabinda, California, Cambodia, Cameroon, Canary Is., Cape Provinces, Cape Verde, Caprivi Strip, Caroline Is., Cayman Is., Central African Repu, Central European Rus, Chad, Chagos Archipelago, Chile Central, Chile North, China North-Central, China South-Central, China Southeast, Chita, Christmas I., Cocos (Keeling) Is., Colombia, Colorado, Comoros, Congo, Connecticut, Corse, Costa Rica, Cuba, Cyprus, Czechoslovakia, Delaware, Denmark, District of Columbia, Dominican Republic, East Aegean Is., East European Russia, Ecuador, Egypt, El Salvador, Equatorial Guinea, Eritrea, Ethiopia, Fiji, Finland, Florida, France, Free State, French Guiana, Føroyar, Gabon, Galápagos, Gambia, Georgia, Germany, Ghana, Great Britain, Greece, Guatemala, Guinea, Guinea-Bissau, Gulf of Guinea Is., Guyana, Haiti, Hawaii, Honduras, Hungary, Iceland, Idaho, Idaho, Illinois, India, Indiana, Inner Mongolia, Iowa, Iran, Iraq, Ireland, Irkutsk, Italy, Ivory Coast, Jamaica, Japan, Jawa, Kamchatka, Kansas, Kazakhstan, Kentucky, Kenya, Khabarovsk, Kirgizstan, Korea, Krasnoyarsk, Kriti, Krym, Kuril Is., KwaZulu-Natal, Labrador, Lebanon-Syria, Leeward Is., Lesotho, Lesser Sunda Is., Liberia, Libya, Louisiana, Madagascar, Madeira, Magadan, Maine, Malawi, Malaya, Mali, Maluku, Manchuria, Manitoba, Maryland, Masachusettes, Mauritania, Mauritius, Mexico Central, Mexico Gulf, Mexico Northeast, Mexico Northwest, Mexico Southeast, Mexico Southwest, Michigan, Minnesota, Mississippi, Missouri, Mongolia, Montana, Morocco, Mozambique, Mozambique Channel I, Myanmar, Namibia, Nebraska, Nepal, Netherlands, Netherlands Antilles, Nevada, New Brunswick, New Caledonia, New Guinea, New Hampshire, New Jersey, New Mexico, New South Wales, New York, New Zealand North, New Zealand South, Newfoundland, Nicaragua, Niger, Nigeria, Norfolk Is., North Carolina, North Caucasus, North Dakota, North European Russi, Northern Provinces, Northern Territory, Northwest European R, Norway, Nova Scotia, Ohio, Oklahoma, Ontario, Oregon, Pakistan, Palestine, Panamá, Paraguay, Pennsylvania, Peru, Philippines, Poland, Portugal, Primorye, Prince Edward I., Puerto Rico, Qinghai, Queensland, Québec, Rhode I., Rodrigues, Romania, Rwanda, Réunion, Sakhalin, Samoa, Sardegna, Saskatchewan, Senegal, Seychelles, Sicilia, Sierra Leone, Sinai, South Australia, South Carolina, South Dakota, South European Russi, Southwest Caribbean, Spain, Sudan, Sulawesi, Sumatera, Suriname, Svalbard, Swaziland, Sweden, Switzerland, Tadzhikistan, Taiwan, Tanzania, Tasmania, Tennessee, Texas, Thailand, Togo, Tonga, Transcaucasus, Trinidad-Tobago, Tunisia, Turkey, Turkey-in-Europe, Turkmenistan, Turks-Caicos Is., Tuva, Uganda, Ukraine, Uruguay, Utah, Uzbekistan, Venezuela, Venezuelan Antilles, Vermont, Victoria, Vietnam, Virginia, Washington, West Himalaya, West Siberia, West Virginia, Western Australia, Western Sahara, Windward Is., Wisconsin, Wyoming, Xinjiang, Yakutskiya, Yugoslavia, Yukon, Zambia, Zaïre, Zimbabwe

    Introduced into:

    Ascension, Assam, Nicobar Is., St.Helena, Yemen

    Common Names

    English
    Duckweed

    Lemna L. appears in other Kew resources:

    Date Reference Identified As Barcode Type Status
    24323.000
    Seychelles 33952.000
    Melville, R. [212], Australia 35448.000
    Harley, R.M. [25515a], Brazil 58015.000
    Chandler, P. [1731], Uganda 22463.000
    Hepper, F.N. [5633], Yemen 34348.000
    Schodde, R. [2674], Papua New Guinea 25394.000
    Melville, R. [2216], Australia 36868.000
    Spruce, R. [s.n.], Peru K000201335

    First published in Sp. Pl.: 970 (1753)

    Accepted by

    • Govaerts, R. & Frodin, D.G. (2002). World Checklist and Bibliography of Araceae (and Acoraceae): 1-560. The Board of Trustees of the Royal Botanic Gardens, Kew.

    Literature

    Flora of West Tropical Africa
    • F.T.A. 8: 200.
    • Sp. Pl. 970 (1753)
    Flora of Tropical East Africa
    • Daubs, Monogr. Lemnac.: 16 (1965)
    • N.E. Br. in F.T.A. 8: 201 (1901)
    • Hegelm., Lemnac. Monogr.: 134 (1868)
    • L., Gen. Pl., ed. 5: 417 (1754)
    • Sp. Pl.: 970 (1753)

    Sources

    CATE Araceae
    Haigh, A., Clark, B., Reynolds, L., Mayo, S.J., Croat, T.B., Lay, L., Boyce, P.C., Mora, M., Bogner, J., Sellaro, M., Wong, S.Y., Kostelac, C., Grayum, M.H., Keating, R.C., Ruckert, G., Naylor, M.F. and Hay, A., CATE Araceae, 17 Dec 2011.
    http://creativecommons.org/licenses/by-nc-sa/3.0

    Flora of Tropical East Africa
    Flora of Tropical East Africa
    http://creativecommons.org/licenses/by-nc-sa/3.0

    Herbarium Catalogue Specimens
    'The Herbarium Catalogue, Royal Botanic Gardens, Kew. Published on the Internet http://www.kew.org/herbcat [accessed on Day Month Year]'. Please enter the date on which you consulted the system.
    Digital Image © Board of Trustees, RBG Kew http://creativecommons.org/licenses/by/3.0/

    Kew Backbone Distributions
    The International Plant Names Index and World Checklist of Selected Plant Families 2018. Published on the Internet at http://www.ipni.org and http://apps.kew.org/wcsp/
    © Copyright 2017 World Checklist of Selected Plant Families. http://creativecommons.org/licenses/by/3.0

    Kew Names and Taxonomic Backbone
    The International Plant Names Index and World Checklist of Selected Plant Families 2018. Published on the Internet at http://www.ipni.org and http://apps.kew.org/wcsp/
    © Copyright 2017 International Plant Names Index and World Checklist of Selected Plant Families. http://creativecommons.org/licenses/by/3.0

    Plants and People Africa
    Common Names from Plants and People Africa http://www.plantsandpeopleafrica.com/
    © Plants and People Africa http://www.plantsandpeopleafrica.com http://creativecommons.org/licenses/by/3.0/