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Genus Campascus

Shell is broadly ovoid; in cross-section circular, ovoid or triangular. Neck is cylindrical, curved. Fundus is rounded or with up to three projections. Aperture is circular, surrounded by a characteristic hyaline collar. Composition of the shell is variable; some species have circular, other amorphous, siliceous scales sometimes mixed with mineral particles, usually not regularly arranged. Ecology: freshwater and marine. Type species: Campascus cornutus Leidy, 1879