Subgenus [ Prostaurastrum ]: lacks arm-like projections (Illustrations of The Japanese Fresh-water Algae, 1977) Species [ var. dickiei ]: Cell body (28-34)-44 μm long (excluding spines), (30-34)-44 μm wide, L/W=1.0, isthmus 7-9 μm wide; semicells nearly elliptical, upper margin more covex than lower margin; each corner with a spine projecting downward; apical view triangular in shape with each side concave. [ var. circulare ]: [ var. latum ]: (Illustrations of The Japanese Fresh-water Algae, 1977).

50 μm 100 μm 150 μm; x 400 : 31 μm 63 μm 94 μm; x 640

Staurastrum dickiei ? (similar to S. cuspidatum), cell body 21 μm long, 21 μm wide (excluding spines), x 400, x 640, Uruguay, November 1999, photo by Yuuji Tsukii