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Genus Cyphoderia

Shell is retort-shaped laterally; ovoid in ventral and dorsal views, usually circular in cross-section, sometimes slightly compressed. Fundus is round or tapered to mammillate tip. Aperture is circular without a collar. Shell is covered by small circular or triangular plates, either adjoining or overlapping on organic matrix depending on species. Endoplasm contains refractive grains. Ecology: marine interstitial, freshwater and moss. Type species: Cyphoderia ampulla (Ehrenberg, 1840) Leidy, 1879