Genus: Similar to Ochromonas, but colourless;
cells ovoid, free-swimming, or attached by a protoplasmic thread, or mutually attached to form
spherical colonies; 1 contractile vacuole (Illustrated Guide, 1985).
cell body 11 μm long, 5 μm wide,
x 640, Watarase river, Ashikaga city, Tochigi Pref., Japan, February 1, 2004 by Y. Tsukii
150 μm; x 400