Genus: Only 1 emergent flagellum; locomotory flagellum directed anteriorly, straight, during swimming; colourless, phagotrophic; no eyespot; rigid, solitary, ovoid, usually flat, with several keels; freshwater (Illustrated Guide, 1985). Oval or pyriform; not plastic; pellicle often with straight or spiral furrow; a single flagellum; many species (Kudo, 1966).
P. bicarinata
2 clips
cell 24 μm
flag. 30-35 μm
or P. dorsalis ?
Japan, 1998