Family: Similar to Euglenidae in body form and general structure, but without chromatophores (chloroplasts); body highly plastic, although usually elongate spidle.
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).
body 25 x 11 μm
flag. 35 μm