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:

50 μm 100 μm 150 μm; x 400 : 31 μm 63 μm 94 μm; x 640