New York Natural Heritage Program
Minute Duckweed
Lemna perpusilla Torr.
Family: (Lemnaceae)

State Protection: Endangered
listed species are those with: 1) 5 or fewer extant sites, or 2) fewer than 1,000 individuals, or 3) restricted to fewer than 4 U.S.G.S. 7 ˝ minute topographical maps, or 4) species listed as endangered by U.S. Department of Interior.

Federal Protection: Not Listed

State Rarity Rank: S1
A State Rarity Rank of S1 means: This plant is endangered/critically imperiled in New York because of extreme rarity (typically 5 or fewer populations or very few remaining individuals) or is extremely vulnerable to extirpation from New York due to biological factors.

Global Rarity Rank: G5
A Global Rarity Rank of G5 means: This species is demonstrably secure globally, though it may be quite rare in parts of its range, especially at the periphery.

Did you know?
Lemna is the ancient Greek name for this water plant given by Theophrastus, the “Father of Botany.” The species name means very small (Fernald 1950) and is a good name for a plant no bigger than the point of a pencil.

State Ranking Justification [-]
There are three existing populations but there is no detailed information on their size and quality. The plant was recorded in 18 different locations between the late 1800s and the mid-1940s and most of them still need to be rechecked. Five populations no longer exist because their habitat has been destroyed.

Short-term Trends [-]

Long-term Trends [-]