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: with arm-like projections (Illustrations of The Japanese Fresh-water Algae, 1977) Species [var. pelagicum ]: Semicells elongate cup-shaped (excluding arms); cell body 40-46 μm long (excluding arms), 50-65 wide (including arms), isthmus 12-13 μm wide (Illustrations of The Japanese Fresh-water Algae, 1977)

31 μm 63 μm 94 μm; x 640

Images of collecting locality: No.2, Saiko (Lake Sai) at Doman-green park, Toda city, Saitama Pref., Japan, December 2, 2007 by Y. Tsukii