Genus: Only 1 flagellum emergent from canal, colourless; eyespot absent; cell body fusiform or elongated, plastic, with pronounced euglenoid movement; many species, mostly freshwater (Illustrated Guide, 1985).
Species: Cell body cylindroid with posterior end rounded, 45 μm long, 10 μm wide; a flagellum more or less longer than the body length; ovoidal paramylum granules (WPRNO).