Section [ Actinotaenium ]:
Cell body cylindrical, slightly constricted at the center, cell surface smooth or dotted or punctated
(Illustrations of The Japanese Fresh-water Algae, 1977).
Species:
Cell body small, 22-(32-43)-60 μm long, 10.5-(20-23)-32 μm wide,
isthmus 9.5-(18-21.5)-30 μm wide, L/W=2; semicells ovoidal;
(Illustrations of the Japanese Fresh-water Algae, 1977).
Cosmarium curtum (Brébisson) Ralfs ??,
cell body 42 μm long, 23 μm wide, L/W=1.8, isthmus 22 μm wide,
x 640, standing water under Akigase bridge, Akigase park, Saitama city, Saitama Pref., Japan, February 27, 2005 by Y. Tsukii
31 μm
63 μm
94 μm; x 640
Cosmarium curtum (Brébisson) Ralfs:
Cell body small, 22-(32-43)-60 μm long, 10.5-(20-23)-32 μm wide,
isthmus 9.5-(18-21.5)-30 μm wide, L/W=2; semicells ovoidal;
(Illustrations of the Japanese Fresh-water Algae, 1977).