Subgenus: Entomum (Apical area deeply indented or notched)
Section: Incisa (Cell surface smooth; apical area without spiny projections)
Species: Cell body μm long, μm wide, L/W=,
isthmus μm wide;
(Illustrations of The Japanese Fresh-water Algae, 1977).
Euastrum ampullaceum Ralfs,
cell body μm long, μm wide, L/W=, isthmus μm wide,
x 640, Shibakusadaira (marsh), Zao mountain, Shichigashuku town, Miyagi Pref., Japan, August 17, 2007 by Y. Tsukii
31 μm
63 μm
94 μm; x 640
Cell body μm long, μm wide, L/W=, isthmus μm wide, x 640
Images of collecting locality:
Shibakusadaira (marsh), Zao mountain, Shichigashuku town, Miyagi Pref., Japan, August 17, 2007 by Y. Tsukii