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Genus Lesquereusia

Shell with asymmetrical neck, more or less attached to the body; composed of endogenous siliceous rods or in some species with collected mineral particles in structured mesh-like cement. Fundus is rounded. Aperture is located at the end of the neck, circular in cross section. Ecology: freshwater. Type species: Lesquereusia spiralis (Ehrenberg, 1840) Bütschli, 1888