Family: Cell wall with 2 or more partitions.
Subfamily: Cell division occurs at central constriction.
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).
arm tips separated into two nail-like projections,
x 400, x 640, Uruguay Nov. 1999, photo by Yuuji Tsukii
50 μm 100 μm 150 μm; x 400 : 31 μm 63 μm 94 μm; x 640