Genus: Similar to Cryptomonas in general body form and
structure, but colorless; without pyrenoid; "cytopharynx" (gullet) deep, lower half surrounded by granules
(ejectisome/trichocyst); one contractile vacuole anterior (Kudo, 1966).
Species: 20-40 μm long (How to know the protozoa, 1979). Posteriorly narrowed; slightly bent 'dorsally'; 30-40 μm long, 10-15 μm wide; widely distributed in stagnant water (Kudo, 1966). 8-15 μm long, 4-6 μm wide (Illustrations of The Japanese Fresh-water Algae, 1977).