Genus: Unicellular; planktonic; cell body flat, ovoidal; two flagella emerging from anterior end, one extends anteriorly and
another posteriorly; a reservoir and a contractile vacuole present, trichocysts absent;
many chloroplasts ellipsoidal in shape, light green in color
(Guide book to the "Photomicrographs of the Freshwater Algae", 1998).
Species: Cell body ovoidal, slightly compressed, 40-65 μm long, 25-35 μm wide; a nucleus elongated ellipsoidal, located at the center of the cell body; resorvoir and contractile vacuole located anterior end; many disc-shaped chloroplasts light-green, elongated ellipsoidal; many refractile granules at periphery of the cell; pellicle soft; trailing flagellum slightly shorter than the cell body (Illustrations of Japanese fresh-water algae, 1977).