Coralliophila costularis (Lamarck, 1816) (Figs 2 A-C; 12B)

Murex costularis Lamarck, 1816: pl. 419, figs 8a, b. Coralliophila retusa H. Adams & A. Adams, 1863: 432 .

TYPE MATERIAL. — Murex costularis: 2 specimens (the probable holotype MHNG 1099/60/1, 34.0 mm, and a specimen that is probably not a type, 1099/60/2, 26.4 mm: see Oliverio 2008b).

Coralliophila retusa: holotype, BMNH 1984094 (figured by Kosuge & Suzuki [1985: pl. 37, fig. 3] and Higo et al. [2001: 65, fig. G2386]).

TYPE LOCALITY. — Murex costularis: not designated. Locality indicated on its box reads “Oc. Indien ”. Coralliophila retusa: unknown.

MATERIAL EXAMINED. — The type material and: BENTHAUS, stn DW 2013, Rimatara Is., 22°38.6’S, 152°49.7’W, 80-93 m, 1 juv dd (Fig. 2C). — Stn DW 1948, Banc Lotus, 23°48.7’S, 147°43.5’W, 120-280 m, 1 dd (Fig. 2A, B).

DISTRIBUTION. — Indo-Pacific, intertidal and subtidal (Cernohorsky 1978). Indian Ocean, from the Red Sea southward to South Africa (Kosuge & Meyer 1999) and the tropical and subtropical zone, including Eastern Arabia “among corals” (Bosch et al. 1995). Western Pacific Ocean, intertidal to 20 m depth associated with scleractinians (Tsuchiya 2000). From the New Caledonia area and Fiji, alive in 12-40 m (Oliverio 2008b). Austral Islands, two empty shells in 93-120 m, probably drifted from shallower waters.

REMARKS

Coralliophila costularis is a common shallow water species throughout its Indo-West Pacific range. The present record is based on a single adult empty shell and a single juvenile, both dredged in deep waters. The protoconch of the juvenile was available for SEM (Fig. 12B), and showed 4.3 whorls, 590 µm high and 710 µm wide at the base. Protoconch I of one whorl, apparently smooth. Protoconch II of about 3 ¼ whorls, with two weak spiral keels (the abapical starting on the second protoconch whorl, the adapical starting on the third), sculptured by a series of subsutural threads and a series of opisthocline threads over each keel. A diffuse granulation is present in the interspaces. Coralliophila mira (Cotton & Godfrey, 1932) from southern Australia is very similar although relationships should be tested by genetic data.