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Genus Protoplagiopyxis

Shell is ovoid in frontal view, hemispheric with anterior flattening in lateral view; covered by extraneous mineral particles. Ventral surface is flattened very clearly and slightly or not inclined. Aperture is a straight or crescent-shaped slit of “plagiostome” type with tendency to “cryptostome” (aperture located inside the shell), no vestibule, but apertural region is well separated by fairly abrupt dorso-ventral depression in the anterior part. Ecology: soils. Type species: Protoplagiopyxis delamarei Bonnet, 1962