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Emarginula superba (Hedley & Petterd, 1906) Description: Shell light in weight, base oval or nearly so, widest at centre or slightly posteriorly. Apex at or behind posterior third, backward pointing and recurved. Anterior slope convex, posterior slope concave. Slit in anterior margin about a fifth of anterior slope length. Selenizone flat, not elevated above surrounding shell surface, with fine, thin bordering flanges and crossed by fine, close lunulae. Shell sculptured with about 60 sharp radial ribs with fine secondary ribs between, both densely scaled. Margin irregular, crenulate internally. Colour fawn with some white ribs, and concentric lighter or darker rings; dead shells usually bleached uniformly white. Size: Up to 29 mm in length. Distribution: Endemic to Australia: Crowdy Head, NSW to Great Australian Bight, including Tasmania. Habitat: Taken in 90-500 m. Uncommon. Remarks: Fig. 2 shows a range of specimens with a wide variation in shell height and position of apex. Either the species is very plastic or there is more than one species involved. Fig. 2c matches Emarginula gabensis (Gabriel, 1962) which was described as being taller than E. superba, with a narrower selenizone and longer slit. Fig. 1 Off Cape Conran, Victoria, in 146-183 m (C.353903) Fig. 2 a. Off Port Kembla, NSW, in 466 m (C.310153) b. Off Wollongong, NSW, in 439 m (C.120414) c. Stanwell Park, NSW, 91 m (C.066030)
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