Order & Family: Floating unicells or a colony embedded in a matrix; no differentiation of apical and base structures; only one family. Genus: A colony of elliptical cells; each cell without a sheath or with a thin sheath, both ends of the cells spherical, not curved (Illustrations of The Japanese Fresh-water Algae, 1977).

31 μm 63 μm 94 μm; x 640

Images of collecting locality: Tane-ike (pond), Togakushi highland, Shinano town, Nagano Pref., Japan, May 21, 2006 by Y. Tsukii