Species: Cell body broad ellipsoidal, cylindrical, or inverted ovoid, both ends rounded, 20-32 μm long, 13-27 μm wide; cellwall thick; covered by two layers of gelatinous sheaths; papilla broad, short, rounded at corners; length of flagella nearly the same as that of cell body; chloroplast cup-shaped, filling whole cell; stigma rounded, at equator or slightly anterior; nucleus centrally located; two apical contractile vacuoles at the base of flagella. [var. subporosa (Skuja) Ettl 1993]: Cell body larger (26-28 x 25-32 μm); inner cellwall finely porous; sexual reproduction by heterogamy (Süßwasserflora von Mitteleuropa 9, Chlorophyta I, 1983).

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