Japan Flora: Fronds flat, broadly obovate, 5-8 mm. long, 4-6 mm. wide, rounded to a very obtuse apex, purplish below, with 6-11 descending roots 3-5 cm. long, palmately 5- to 11-nerved, the lateral gemmae (daughter fronds) pro­duced from the edges near the attachment of the root; autum­nal fronds or winter buds orbicular, thickish; flowers globose, surrounded by a small spathe; inflorescence composed of 3 flowers, 2 staminate and 1 pistillate.  Common in ditches, ponds, and paddy fields.

Hokkaido, Honshu, Shikoku, Kyu­shu. Cosmopolitan.