Genus: Cell body short, radiate in shape; apical view of the cell, triangular, polygonal, ellipsoidal or spindle-shaped; zygospores formed outside of mother cells (Illustrations of The Japanese Fresh-water Algae, 1977)
Subgenus: lacks arm-like projections (Illustrations of The Japanese Fresh-water Algae, 1977)
Species: cell body without spines 32-42 μm long, 34-39 μm wide (without spines), constriction 11-167 μm wide, (Illustrations of The Japanese Fresh-water Algae, 1977)