Genus: Arrangement of 4 daughter cells flat and rectangular in shape, forming composite coenobium; without gelatinous sheaths, no hairly projections (Illustrations of the Japanese Freshwater Algae, 1977). Species: Colonies of 4 cells; cell body triangular in shape, 4-10 μm wide; a single chloroplast plate-like, with a pyrenoid (Illustrations of the Japanese Freshwater Algae, 1977).

50 μm 100 μm 150 μm; x 400