Arcella grospietschi Stepanek, 1963
Diagnosis: Shell disc-shaped, yellow-brown, in ventral view with a undulated border, with seven large and seven smaller lobes. Near the aperture, the wall changes into a thinner, skin-like enclosure that is bent back into the interior of the shell. This collar or enclosure is also flap-like, but not as clear as the border of the shell. The edge of the collar is yellowish, not very transparent.
Dimensions: Diameter 132-146 µm, height 28 µm, aperture 35-42 µm.
Ecology: Freshwater. Central Africa.
Remarks: Stepanek (1963): “Two shells were found with the plasma, unfortunately after fixation these lost their original shape. Nevertheless, two nuclei and some larger vacuoles were found. A total of 5 shells were found in two locations that were rather far apart from one another, but with the same geographical latitude.”