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Genus Mrabella

Shell is elongated-pyriform, laterally compressed, with the lateral sides gradually tapering toward the aperture. Lateral margins distinctly compressed giving the impression of a thick and wide hollow keel. Because of this, the shell is elongated elliptical with the pointed end in the profile. Shell colourless, composed of quadrangular shell plates similar to those in Quadrulella species. Type species: Mrabella subcarinata (Gauthier-Lièvre, 1957)