Genus: Emergent flagellum mobile throughout its length during swimming; colourless; no eyespot;
cell body rigid; cylindrical, not flattened; canal opening subapical; paramylon and lipid abundant;
fresh water (Illustrated Guide, 1985).
Body rigid, cylindrical, more or less arched; pellicle longitudinally ridged;
a flagellum at apex (Kudo, 1966).
Species: Banana-shaped; longitudinal ridges; flagellum as long as cell body;
15-25 μm long,
7-8 μm wide (Hall, 1923),
13-15 μm long,
5-7 μm wide (Hollande, 1952);
standing water (Kudo, 1966).
