Genus: Colony of 4, 8 or 16 cells, within a gelatinous sheath, which is spherical or ellipsoidal in shape;
cell body broad crescent in shape, both ends rounded;
a single chloroplast plate-like in shape, with a pyrenoid
(Guide book to the "Photomicrographs of the Freshwater Algae", 1998).
Species: Colonies of 4-8 cells within a gelatinous sheath; cell body slightly curved reniform, 10-15 μm long, 5-6 μm wide (Illustrations of The Japanese Fresh-water Algae, 1977).