Genus: Cingulum (horizontal groove) located at the center of the body
(Illustrations of The Japanese Fresh-water Algae, 1977).
Cingulum more or less median; sulcus straight (Illrustrated Guide, 1985).
cell body 35 μm long, 35 μm wide, L/W=1.0,
x 640, Nanbata castle park, Fujimi city, Saitama Pref., Japan, September 18, 2005 by Y. Tsukii
94 μm; x 640