Genus: Unicellular; variable in shape; a constriction at the center of the cell body;
mostly longer than wide; flattened; each semicell hemispherical, spherical, ellipsoidal,
rectangular, pyramidal or kidney-shaped; no apical indentation
(Illustrations of The Japanese Fresh-water Algae, 1977).
Images of collecting locality:
a pond near the entrance of climbing route to Omine mountain, Minakami town, Gunma Pref., Japan, October 21, 2007 by Y. Tsukii