
Lemna trisulca

Lemna trisulca L. (syn. "Staurogeton trisulcus" (L.) Schur; star duckweed; ivy-leaved duckweed) is a species of aquatic plants in the arum family Araceae. It has a subcosmopolitan distribution. Unlike other duckweeds, it has submerged rather than floating fronds, except when flowering or fruiting.
Description.
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.
Distribution.
This species is widely distributed in cool-temperate regions, including Great Britain and Ireland, Asia (Bangladesh, China (Northern, Western, Southern [Taiwan, Yunnan]), India (Eastern, Northern), Indonesia (Sumatra, New Guinea), Brunei, Japan, Malaysia, Myanmar, Papua New Guinea, Pakistan, Philippines); Europe; Oceania; N. America; and S. America.