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Genus Zivkovicia

Shell is pyriform, mostly with a distinct constriction of the neck which sometimes can be obscured by larger mineral particles, circular or compressed in cross section, built of agglutinated mineral particles bound by a structured organic cement. The neck is separated from the main body of the shell by an internal mineral diagram with two circular openings. Aperture is terminal, circular. Ecology: freshwater. Type species: Zivkovicia compressa (Carter, 1864)