Genus: Body colorless; plastic; flask-shaped; striated; a funnel-like neck;
posterior region stout; a single flagellum protruded from
funnel and reaches inward the posterior third of body (Kudo, 1966).
cell body 35 μm long, 17 μm wide, L/W=2.1,
anterior flagellum 50 μm long,
x 640, Onnenai, Kushiro marsh, Kushiro city, Hokkaido, Japan, October 16, 2005 by Y. Tsukii
94 μm; x 640