world of amoeboid organisms

Arcella grospietschi
Arcella grospietschi, after Stepanek, 1963

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.

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