Species [ var. diplosporum ]: Cell body medium in size, cylindrical, slightly constricted at center,
52-66 μm long, 23-33 μm wide, L/W=2.0;
semicells slightly-ellipsoidal cylindroid, apex broadly rounded; cell wall finely dotted,
chloroplasts consisting of longitudinal axis and radially-arranged laminae.
[ var. major ]: Larger than var. diplosporum, (98)-102-115 μm long,
43-47 μm wide
(Illustrations of The Japanese Fresh-water Algae, 1977).
Cosmarium diplosporum (Lundell) Lütkemüller large var. ?? (Actinotaenium),
with Mesotaenium endlicherianum,
cell body 47 μm long, 26 μm wide, isthmus 23 μm wide,
x 640, Japan, 2004 by Y. Tsukii
31 μm
63 μm
94 μm; x 640