Lemnaceae

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Lemnaceae (duckweeds) A monocotyledonous (see MONOCOTYLEDON) family of small, freshwater, aquatic, often floating herbs which are reduced relatives of Araceae and have a disc-like, oval or elliptical, flattened or swollen plant body, not differentiated into stem and leaves, few or no roots, and minute flowers often enclosed in a tiny sheath. The spathe subtends 1 female and 2 male, apetalous flowers. The sexes are separate on any one plant and not always produced. There are 6 genera, with about 30 species, of cosmopolitan distribution.