Genus: Colonies small, spherical or aggregates in shape; sheath inconspicuous or absent; cell body spherical in shape;
chloroplasts cup-shaped or plate-like (Illustrations of the Japanese fresh-water algae, 1977).
daughter cell body about 8 μm in diam.,
x 640, Okubo Ryoke (picnic-no-mori), Akigase park, Saitama city, Saitama Pref., Japan, February 27, 2005 by Y. Tsukii
94 μm; x 640