Genus (Diesing): Cells obovate or almost spherical, flattened dorsoventrally;
rod-shaped trichocysts around cell periphery or concentrated at the 2 ends of the cell;
flagella usually same length as cell; but trailing flagellum may reach twice that length;
many chloroplasts in a single layer in the cell periphery (Illustrated Guide, 1985).
(Illustrations of The Japanese Fresh-water Algae, 1977).
Species: Cell body inverted ovoidal, posterior end pointed, compressed dorso-ventrally, 45-70 μm long, 20-30 μm wide, 10-20 μm in thickness; a nucleus ellipsoidal, located at the center of the cell body; a resorvoir and contractile vacuole at the anterior end; many chloroplasts light-green, disc-shaped at periphery of the cell; trichocysts anteriorly many and scattered posteriorly (Illustrations of Japanese fresh-water algae, 1977).