Genus: Euglenas in a close fitting lorica; a single long flagellum extends through small opening; lorica with or without short collar; yellow to brown (How to know the protozoa, 1979). Lorica often possesses numerous spines, composed of ferric hydroxide impregnated with brown manganic compound (Kudo, 1966). Species:

T. pulcherrima (elongated ellipsoidal, smooth); T. lacustris (elongated cylindrical, dotted); T. abrupta (cylindrical/ellipsoidal, dotted);

31 μm 63 μm 94 μm; x 640

* Trachelomonas cylindrica Ehrenberg var. cylindrica: Lorica long cylindroid, smooth, rounded at both end; collar very short or absent; 15-20 μm long, 8-10 μm diam. (Illustrations of The Japanese Fresh-water Algae, 1977).

Trachelomonas volzii Lemmermann var. cylindracea Playfair: Lorica pear-shaped, slightly long; collar long, thick at base; 23-24 μm long, 14-15 μm diam. (Illustrations of The Japanese Fresh-water Algae, 1977).

Trachelomonas teres: 35 μm; lorica ovoid, with distinct collar (How to know the protozoa, 1979).