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Arcellajurassica
Arcella jurassica, after Olivier, 1944

Arcella jurassica  Olivier, 1944
Synonym: Arcella catinus Penard, 1890

Diagnosis: Test pyramid-shaped but strongly truncated, in lateral view trapezium-shaped, with 5-8 planes; pseudostome surrounded by about 15 pores, each 1-2 µm in diameter. In dorsal view, there are 5-7 ribs, resembling a star. Dorsal plane polygonal, ventral plane circular.

Dimensions: Diameter 77-90 µm; height 28-34 µm; aperture 15-20 µm.

Ecology: Freshwater. In peat bogs between Hypnaceae, Doubs, France.

Remarks: This is certainly a synonym for A. catinus, which Oliver does not mention at all.

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