Wolffia 3716647 208262078 2008-04-26T04:30:49Z 67.101.7.171 {{Taxobox | name = ''Wolffia'' | image = WolffiaArrhiza2.jpg | image_width = 270px | image_caption = Many individual ''[[Wolffia arrhiza]]'' | regnum = [[Plant]]ae | divisio = [[Flowering plant|Magnoliophyta]] | classis = [[Liliopsida]] | ordo = [[Alismatales]] | familia = [[Araceae]] | genus = '''''Wolffia''''' | genus_authority = [[Johann Horkel|Horkel]] ex [[Matthias Jakob Schleiden|Schleid.]] | subdivision_ranks = Species | subdivision = 9-11, see text }} '''''Wolffia''''' is a genus of 9 to 11 species which include the smallest [[flowering plant]]s on Earth. Commonly called '''watermeal''', these [[aquatic plant]]s resemble specks of [[cornmeal]] floating on the water. ''Wolffia'' species are free-floating [[Thallus|thalii]], green or yellow-green, and without roots. The flower is produced in a depression on the top surface of the plant body. It has one [[stamen]] and one [[Carpel|pistil]]. Individuals often float together in pairs or form floating mats with related plants, such as ''[[Lemna]]'' and ''[[Spirodela]]'' species. Most species have a very wide distribution across several continents. ''Wolffia'' species are composed of about 40% protein, about the same as the [[soybean]], making them a potential high-protein human food source. They have historically been collected from the water and eaten as a vegetable in much of Asia. Species include: *''[[Wolffia arrhiza]]'' - spotless watermeal *''[[Wolffia borealis]]'' - northern watermeal *''[[Wolffia brasiliensis]]'' - Brazilian watermeal *''[[Wolffia columbiana]]'' - Columbian watermeal *''[[Wolffia globosa]]'' - Asian watermeal [[Image:Duckweeds.jpg|right|thumb|Close up of two different duckweeds: ''Spirodela polyrrhiza'' and ''Wolffia globosa''. The very tiny ''Wolffia'' plants are under 2 mm long]] ==References and external links== *[http://ucjeps.berkeley.edu/cgi-bin/get_JM_treatment.pl?8328,8340 Jepson Manual Treatment] *[http://plants.usda.gov/java/profile?symbol=WOLFF USDA Plants Profile] *Armstrong, W. (2005) Wayne Armstrong's treatment of the Lemnaceae. [http://waynesword.palomar.edu/1wayindx.htm ]. *Cross, J.W. (2006). The Charms of Duckweed. [http://www.mobot.org/jwcross/duckweed/duckweed.htm] *Landolt, E. (1986) Biosystematic investigations in the family of duckweeds (Lemnaceae). Vol. 2. The family of Lemnaceae - A monographic study. Part 1 of the monograph: Morphology; karyology; ecology; geographic distribution; systematic position; nomenclature; descriptions. Veröff. Geobot. Inst., Stiftung Rübel, ETH, Zurich. * [http://lemna.rutgers.edu The Duckweed Genome Project] [[Category:Alismatales]] [[Category:Aquatic plants]] [[Category:Vegetables]] [[cs:Drobnička]] [[es:Wolffia]] [[fr:Wolffia]] [[nl:Wolffia]] [[ja:ミジンコウキクサ]]