Family: Colonies of a fixed number of cells (4, 8, 16, 32, or more) arranged 2- or 3-dimensionally; cells spherical, ellipsoidal, polygonal, etc. in shape; chloroplasts 1 or several, plate-like in shape, with 1 pyrenoid; asexual reproduction by autocoenobium (Illustrations of The Japanese Fresh-water Algae, 1977).
Genus:
Unidentified sp.
S. asymmetricus ?
S. heimii ?
cell 18 x 5 μm
Omine-numa
Tsukiyono
Gunma, 2003
Unidentified sp.
S. asymmetricus ?
S. heimii ?
cell 15 x 5-6 μm
near Imori pond
Myoko highland
Niigata, 2004
Unidentified sp.
S. asymmetricus ?
S. heimii ?
cell 14 x 3 μm
Hasu-ike
Shiga highland
Nagano, 2005
