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Genus Plagiopyxis

Shell is circular of oval in frontal view, hemispheric in lateral view. Aperture is elongate slit, perpendicular to long axis of the shell; dorsal aperture lip somewhat incurved usually hiding the opening. Ecology: most of the species are edaphobionts (soil-inhabited), some freshwater. Type species: Plagiopyxis declivis Bonnet et Thomas, 1955