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. tortum]: Cell body with 2 arm-like projections, 11 μm long (excluding arms), 28 μm long (including arms), 28 μm wide (including arms), isthmus 4 μm wide. [var. longatum]: 38.7 μm long, 43 υm wide (Illustrations of The Japanese Fresh-water Algae, 1977)

31 μm 63 μm 94 μm; x 640

Images of collecting locality: a pond near Dedono-yu (hot spring), prefectural road route 215, Nishiwaga-machi (town), Iwate Pref., Japan, May 4, 2007 by Y. Tsukii