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Arcella dentata
Arcella dentata

Arcella dentata  Ehrenberg, 1830

Diagnosis: Test circular and dentate in front view, crown-like in profile; diameter more than twice the height; aperture circular, large; colorless to brown; fifteen to seventeen spines; with teeth or dentate border. The ventral side, turned to the substratum, resembles an inverted funnel, with a circular aperture in the centre. The opposite, dorsal side is dish-shaped with flattened vertex, and bears 7-20 spines or ridges; the spines are bent dorsally and more or less evenly spaced around the circumference in a single row.

Dimensions: In literature about 95 µm in diameter, aperture 30 µm in diameter. Diameter with the spines 123-184 µm. The shell of A. dentata is about 120 µm in diameter (107-133 µm, n=25) and about 50 µm in height (41-58 µm, n=25).

Ecology: Bogs and swamps, Sphagnum.

Arcella dentata
Arcella dentata
Arcella dentata
Arcella dentata
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