Genus:
Cell body flat, large, variable in shape, longer than wide; strong constriction at center;
each semicell with several notches; cell wall with many short spines
(Illustrations of The Japanese Fresh-water Algae, 1977).
Species:
cell body 123-195 μm long, 113-186 μm wide
(Illustrations of The Japanese Fresh-water Algae, 1977).