1. Family: Araceae Juss.
    1. Wolffia Horkel ex Schleid

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

    [CATE]

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

    Distribution
    Cosmopolitan.
    General Description
    Fronds thick, globose, ovoid, cylindrical, conical, boat-shaped convex; air spaces lacking; flowers originating in a cavity on or near the median line of the upper surface. Pistil with 1 atropous ovule.
    Diagnostic
    Free floating aquatic plants , reduced to small, leaf-like, poorly differentiated fronds; roots and veins lacking, crystal cells lacking, seeds nearly smooth. Differs from Wolffiella in having fronds globose to ovoid, boat-shaped, without airspaces, daughter fronds produced in a terminal conical cavity of the mother frond, flower originating on the upper side in a cavity in or near the median line of the frond.
    [FTEA]

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

    Habit
    Minute free-floating aquatics
    Thallus
    Daughter thallus produced in a circular lateral pit, soon separating from parent Thallus almost ellipsoid, ± 1 mm. in diameter, flattened on the upper surface at water-level
    Roots
    Roots absent
    Flowers
    Flowers in a pit on the upper surface of the median line, 1 staminate, 1 pistillate; spathe absent.

    Images

    Distribution

    Native to:

    Alabama, Alberta, Algeria, Angola, Argentina Northeast, Argentina Northwest, Arkansas, Assam, Austria, Baltic States, Bangladesh, Belgium, Benin, Bolivia, Botswana, Brazil North, Brazil Northeast, Brazil South, Brazil Southeast, Brazil West-Central, British Columbia, Bulgaria, Burundi, California, Cambodia, Canary Is., Cape Provinces, Central European Rus, Chile Central, China South-Central, China Southeast, Colombia, Colorado, Connecticut, Corse, Cuba, Czechoslovakia, Delaware, District of Columbia, Dominican Republic, East European Russia, Ecuador, El Salvador, Florida, France, Free State, Georgia, Germany, Ghana, Great Britain, Greece, Guatemala, Guinea-Bissau, Hainan, Haiti, Honduras, Hungary, Idaho, Illinois, India, Indiana, Iowa, Iran, Italy, Ivory Coast, Jamaica, Japan, Jawa, Kansas, Kentucky, Kenya, Korea, KwaZulu-Natal, Laos, Lebanon-Syria, Leeward Is., Lesser Sunda Is., Louisiana, Madagascar, Maine, Malaya, Manitoba, Maryland, Masachusettes, Mexico Central, Mexico Northeast, Mexico Northwest, Mexico Southeast, Mexico Southwest, Michigan, Minnesota, Mississippi, Missouri, Morocco, Mozambique, Myanmar, Nansei-shoto, Nebraska, Nepal, Netherlands, Netherlands Antilles, New Guinea, New Hampshire, New Jersey, New South Wales, New York, New Zealand North, New Zealand South, Nigeria, North Carolina, North Caucasus, North Dakota, Northern Provinces, Northern Territory, Ohio, Oklahoma, Ontario, Oregon, Pakistan, Palestine, Paraguay, Pennsylvania, Philippines, Portugal, Puerto Rico, Queensland, Québec, Romania, Rwanda, Saskatchewan, Senegal, Sicilia, South Australia, South Carolina, South Dakota, South European Russi, Spain, Sri Lanka, Sumatera, Suriname, Taiwan, Tanzania, Tasmania, Tennessee, Texas, Thailand, Togo, Transcaucasus, Tunisia, Uganda, Ukraine, Uruguay, Utah, Venezuela, Vermont, Victoria, Vietnam, Virginia, West Himalaya, West Virginia, Western Australia, Windward Is., Wisconsin, Yugoslavia, Zaïre, Zimbabwe

    Introduced into:

    Hawaii

    Wolffia Horkel ex Schleid appears in other Kew resources:

    First published in Beitr. Bot. 1: 233 (1844)

    Accepted by

    • Wu, Z. & Raven, P.H. (eds.) (2010). Flora of China 23: 1-515. Missouri Botanical Garden Press, St. Louis.
    • Dobignard, D. & Chatelain, C. (2010). Index synonymique de la flore d'Afrique du nord 1: 1-455. Éditions des conservatoire et jardin botaniques, Genève.
    • 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: 203.
    • in Linnaea 13: 389 (1839)
    CATE Araceae
    • Royal Botanic Gardens, Kew 2008. World Checklist of Selected Plant Families.
    • Landolt, E. 1998. Lemnaceae The Families and Genera of Flowering Plants.. 4: 264-270
    Flora of Tropical East Africa
    • Daubs, Monogr. Lemnac.: 41 (1965)
    • N.E. Br. in F.T.A. 8: 203 (1901)
    • Hegelm., Lemnac. Monogr.: 121 (1868)
    • in Linnaea 13: 389 (1839)

    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

    Kew Backbone Distributions
    The International Plant Names Index and World Checklist of Selected Plant Families 2020. 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 2020. 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