(Müller, 1786)
Kahl, 1933
Body elongate cylindrical, anterior half narrowed; highly flexible. Cross section circular. Pellicle slightly grooved by kineties. Produces hyaline mucilaginous lorica when undisturbed. Oral cavity narrow and shallow, extends along anterior body half. Contractile vacuole in posterior end. Extrusomes elliptical, in humps between cilia and kineties. Somatic kineties 8-10 in number, kinety left of oral cavity extending very close to adoral membranelle 1, which thus appears to consist of 2 ciliary rows; 1 elongate caudal cilium. Adoral membranelle 1 very long, i.e. extends from anterior end almost to cytostome, composed of single row of cilia; adoral membranelle 2 short, composed of few dikinetids; adoral membranelle 3 small, trapezoidal. Undulating membrane short, C-shaped, on posterior right of oral cavity. Scutica comprises about 3-6 basal bodies. Movement jerky. Size in vivo 60-130 x 10-18 µm. Usually a benthic species.
Ref.: Kahl (1931), Evans and Thompson (1964), Thompson (1968), Didier and Detcheva (1974).