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Genus Deharvengia

Shell is transparent, oval or ovoid in the broad view, circular to narrow elliptical in the cross-section. Aperture elliptic or narrow elliptic, the ventral side is cut at about 6/7 of the length of the entire shell and is surrounded by a thin organic lip. On the dorsal side the shell forms a small cap over the aperture, sometimes with a narrow organic lip along the edge. Shell is covered by elongate-elliptic idiosomes. Transparent clavate spines may be present on each side of the shell (Bobrov et al., 2012). Ecology: freshwater, soils. Type species: Deharvengia papuensis Bonnet, 1979