Genus: Body more or less ovo-cylindrical; rigid with spirally striated pellicle;
often with a short posterior spinous projection; stigma sometimes present;
discoidal chromatophores (chloroplasts) numerous and marginal; paramylum bodies usually
large and ring-shaped, laterally disposed; without pyrenoids; fresh water (Kudo, 1966).
cell body 22 μm long, 17 μm wide, L/W=1.3,
x 640, Nanbata castle park, Fujimi city, Saitama Pref., Japan, September 18, 2005 by Y. Tsukii
31 μm 63 μm 94 μm; x 640