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]]
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[[ja:ミジンコウキクサ]]