Genus: Oval, flattened; more or less rigid; flagella arise from a cytostome, one trailing; protrusible
cytopharynx a long conical tubule (siphon) almost reaching posterior end; fresh water (Kudo, 1966).
Species: About 20 μm long (Kudo, 1966; How to know the protozoa, 1979); trailing flagellum more than twice the length of anterior one (How to know the protozoa, 1979); 20-25 μm long, 10-15 μm wide (Illustrated Guide, 1985); Cell body ovoidal with 6-7 longitudinal grooves, 20-30 μm long, 12-18 μm wide; anterior flagellum nearly the same as the cell body in length, trailing flagellum about twice of the cell body in length (An Illustrated Guide to Freshwater Zooplankton in Japan, 2000).
Images of collecting locality:
Hazama marsh, Tomita, Ashikaga city, Tochigi Pref., Japan, April 22, 2006 by Y. Tsukii