Genus: Colonies of 4 (or 2, 8, 16) cells attached side by side, arranged linearly or zigzag; cell body elliptical or spindle or crescent in shape; terminal cells with spiny projections in many species; cell wall usually smooth, but in some species granulated or dented or ridged (Illustrations of The Japanese Fresh-water Algae, 1977).
Species:
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Similar species -->> S. ovalternus;
S. tibiscensis ?
cell 16 x 5 μm
Kurome River
Asaka
Saitama, 2000
S. tibiscensis ?
cell μm
O-ike park
Yabuki
Fukushima, 2003
S. tibiscensis ?
cell μm
Nashi-ike
Kagami-ishi
Fukushima, 2003
S. tibiscensis ?
cell μm
Senuki
Nasu
Tochigi, 2004