Habitat
Duckweed is a fairly cosmopolitan plant found worldwide. Its habitat is normally listed as mesotrophic to eutrophic, quiet waters in suboceanic, cool, temperate regions with relatively mild winters.

Each dot indicates an area of duckweed occurrence.
Legend for numbers: The
occurrence of Lemnaceae lacking due to:
1 = too dry, 2 = too wet, 3 = too
cold, 5 = not sufficiently explored