Sigapatella calyptraeformis (Lamarck, 1822)
Description: Shell low, coiled, whorls rounded. Apex small and prominent, at posterior third; last whorl greatly expanded to form almost circular base. Sculpture restricted to oblique growth lines, becoming almost concentric on last whorl margin. Basal margin sharply angled; base concave, aperture occupying about half of base area. Exterior colour fawn, apex sometimes violet; interior glossy, white or fawn, sometimes tinged with violet; periostracum furry, brown.
Size: Up to 26 mm diameter, commonly 15-20 mm.
Distribution: Endemic to Australia. Port Stephens, NSW, around southern Australia to Fremantle, WA, including Tasmania.
Habitat: Lives attached to small stones or other shells, preferring the inner surface of dead bivalves, from the shallow subtidal down to 155 m. Moderately common as beach shells.
Remarks: Knudsen (1999) has reported on this species at Rottnest Island, WA.
Fig. 1: Twofold Bay, NSW (C.050057)
Fig. 2: Same specimen as Fig. 1
Fig. 3: Same specimen as Fig. 1
Copyright Des Beechey 2007