Lemna trisulca

Lemna trisulca L. (syn. Staurogeton trisulcus (L.) Schur; star duckweed; ivy-leaved duckweed) is a species of aquatic plants in the genus Lemna (duckweed) with a subcosmopolitan distribution, occurring in quiet, freshwater habitats in cool, temperate regions. L. trisulca normally does not occur in warm, temperate regions. Unlike other duckweeds, it has submerged rather than floating fronds, except when flowering or fruiting. The leaves usually grow submerged and are oblong-lanceolate in shape and are up to 14 mm long. They are blunt at the end and taper to a tail-like stalk at the other. This species is widely distributed in cool-temperate regions, including Great Britain and Ireland, Asia (Bangladesh, China (Northern, Western, Southern ), India (Eastern, Northern), Indonesia (Sumatra, New Guinea), Brunei, Japan, Malaysia, Myanmar, Papua New Guinea, Pakistan, Philippines); Europe; Oceania; N. America; and S. America.