Wolffiella

About

Wolffiella is a genus of aquatic plants commonly called duckweeds in the family Araceae. Common names for plants in this genus include bogmat and mud-midget. They are rootless and have a keel that allows them to maintain their orientation in the water. They are small, measuring 2 mm (0.08 in) to 10 mm (0.4 in) in width.

Summary from Wikipedia