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Genus Playfairina

Shell is circular in cross section, tapering towards the aperture; fundus rounded or pointed. Shell is covered large and small idiosomes, arrangement in most cases as in Trinema. Aperture is circular, not invaginated, surrounded by one row of denticulated marginal plates. Pseudopoida are unknown, but doe to the homologies in shell morphology Playfairina is placed here. Two species. Ecology: mosses, soils. Type species: Playfairina caudata (Playfair, 1917) Thomas, 1961