Species [ var. coarctatum ]: Cell body 24-33.3 μm long, 28-40 μm wide,
L/W=, isthmus 6.5-9 μm wide; corners rounded, slightly curved upward;
apex slightly concave.
[ var. subcurtum Nordstedt ]:
Cell body 20-28 μm long, 16-28.7 μm wide,
L/W=, isthmus 5.5-12 μm wide
(Illustrations of The Japanese Fresh-water Algae, 1977)
Similar species -->>S. lapponicum;
S. alternans;
Staurastrum coarctatum Brébisson var. coacrtatum ?
(or S. bieneanum var. orientale W. et G.S. West ?),
cell body μm long, μm wide, L/W=, isthmus μm wide,
x 640, No.10 (Suimei-no-hotori), Kannon-numa Forest Park (pond), Shimogo town, Fukushima Pref., Japan, November 15, 2008, by Y. Tsukii 31 μm
63 μm
94 μm; x 640
Images of collecting locality:
No.10 (Suimei-no-hotori), Kannon-numa Forest Park (pond), Shimogo town, Fukushima Pref., Japan, November 15, 2008, by Y. Tsukii