Genus: Colony within a gelatinous bag; cells uniformly arranged at the peripheral matrix;
cell body spherical or ellipsoidal with 2 pseudo-flagella; 2-4 cells form a small subset;
a single chloroplast cup-shaped, with a pyrenoid
(Guide book to the "Photomicrographs of the Freshwater Algae", 1998).
Small colonies planktonic or large ones attached to other substrates
(Illustrations of The Japanese Fresh-water Algae, 1977).
Images of collecting locality:
Kawaguchi Natural Park, Sashima, Kawaguchi city, Saitama Pref., Japan, February 5, 2006 by Y. Tsukii