(Gray in G. B. Sowerby II, 1832)
Shell globular, ends slightly extended, spire concealed, aperture almost semicircular. Covered with strong ribs, about 27 on the outer lip, interrupted by a deep dorsal groove, which extends almost the whole length of the shell. Fossula deep, crossed by ribs, extending as a broad groove within the aperture for whole length of shell. Colour white.
Size: Length up to 7 mm