Genus: Test variable, chitinoid; binucleate (Illustrated Guide, 1985).
Species: Diam. 180-360 μm, height 36-55 μm; pseudostome, round, 70-190 μm; with ring of pores (Illustrated Guide, 1985). |
Arcella discoides Ehrenberg, 1871: Diam. 90-150 μm, height 25-30 μm; pseudostome, round, 30-40 μm; with or without ring of pores (Illustrated Guide, 1985).