Species [ var. connatum ]:
Cell body 22-24 μm long,
19.6-25 μm wide (excluding spines), isthmus 7-9 μm wide;
spines short; semicells inverted semicircle in shape, apex flat or slightly convex.
[ var. pseudamericanum Grönblad ]: Cell body larger than v. connatum 39-45 μm long, 25-36.45 μm wide (excluding spines), isthmus 5.6-11 μm wide; corners of semicells protruded upward making its apex concave. [ var. rectangulum Roy et Bisset ]: Cell body 14-20 μm long, 14.7-20 μm wide (without spines), isthmus 3.5-5.6 μm wide; side margins of semicells not convex; spines longer and thicker than v. connatum (Illustrations of The Japanese Fresh-water Algae, 1977) |
31 μm
63 μm
94 μm; x 640
Staurastrum,
cell body 24 μm long, 24 μm wide, L/W=1.0, isthmus 8 μm wide,
x 640, Onnenai, Kushiro marsh, Kushiro city, Hokkaido, Japan, October 16, 2005 by Y. Tsukii
31 μm
63 μm
94 μm; x 640
