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 small, (22.4-25)-30 μm long, (28)-34 μm wide, L/W=1, isthmus 5-(7.8-9) μm wide; semicells elliptical or triangular in side view, apex slightly convex, laterally strongly convex; dichotomous projections at each corner; apical view triangular (Illustrations of The Japanese Fresh-water Algae, 1977)

31 μm 63 μm 94 μm; x 640

Images of collecting locality: Marsh pond along climbing route near Mida-ga-hara (bog/marsh), Gassan (mountain), Tsuruoka city (formerly Haguro town) & Shonai town (formerly Tachikawa town), Yamagata Pref., Japan, August 3, 2006 by Y. Tsukii