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RISSOIDAE |
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Alvania (Linemera) suprasculpta May, 1916 Description: Shell moderately tall, spire convex. Protoconch of 1¼ whorls, junction with teleoconch distinct. Teleoconch up to 4 strongly convex whorls. Axial sculpture of thin ribs, sometimes lamellose, 20-40 on last whorl. Spiral sculpture of strong cords, 3 on spire whorls, forming peaks at intersections with axials; pits between axials and spirals very finely striate. Last whorl with further 5 strong spiral cords on base. Aperture ovate, with well-defined posterior canal; smooth internally, outer lip expanded and thickened with varix externally. Shell fawn, rarely with fawn periostracum. Size: Up to 2.5 mm in length. Distribution: Endemic to Australia: central Queensland, southwards to Tasmania and South Australia. Habitat: Known from a few beach specimens, but mainly subtidal 7-366 m. Common. Comparison: The fine striae in the pits between the axial and the radial ribs identify this species. Synonymy: A synonym is Merelina subreticulata Laseron, 1950 Remarks: This species is fairly variable in shape and sculpture. Some specimens are relatively short and wide, similar in shape to A. strangei, but others are more tall and slender. The axial ribs may be low and rounded or elevated, lamellose in parts of some shells. The number of axial ribs varies from about 20 to 40, making the striate interspaces square or narrowly rectangular. The wide geographic and depth range over which this species is recorded is suspicious, suggesting that more than one species is involved. Fig. 1: Middle Harbour, Sydney, NSW (C.032471 Fig. 2: Original figure from May (1916)
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