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Genus Corythionella

Shell is ovoid, dorso-ventrally compressed; fundus is rounded. Aperture is circular, located on the ventral side, surrounded by large circular collar. Shell is covered with elongate, siliceous idiosomes, irregularly arranged as in Corythion, the plates of the collar are smaller (Nicholls, 2009b). Ecology: marine and freshwater interstitial. Type species: Corythionella pontica Golemansky, 1970