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). Species:

50 μm 100 μm 150 μm; x 400

cf.
C. moewusii Gerloff: 9-16 μm long, 5-8 μm wide; ellipsoidal to subcylindrical; chloroplast urn-shaped; pyrenoid laterial; stigma present (Illustrated Guide, 1985).