Species: Cell body small, (20-22)-42 μm long, (10.5-11)-17 μm wide,
L/W=2-2.5; slightly depressed at the center; semicells gradually attenuated toward apex,
lateral margins nearly straight, apex flat with rounded corners; cell wall smooth
(Illustrations of The Japanese Fresh-water Algae, 1977).
Cosmarium parvulum Brébisson,
cell body 40 μm long, 17 μm wide, L/W=2.4, isthmus 15 μm wide,
x 640, No.1, a marsh pond at Sensho-ga-hara, near Akita-komagadake (mountain), Shizukuishi town, Iwate Pref., Japan, August 6, 2007 by Y. Tsukii
31 μm
63 μm
94 μm; x 640
Images of collecting locality:
No.1, a marsh pond at Sensho-ga-hara, near Akita-komagadake (mountain), Shizukuishi town, Iwate Pref., Japan, August 6, 2007 by Y. Tsukii