Rhizochilus cf. antipathum Steenstrup, 1850

Oliverio, Marco, 2008, Coralliophilinae (Neogastropoda: Muricidae) from the southwest Pacific, Mémoires du Muséum national d'Histoire naturelle 196, pp. 481-586 : 519

Rhizochilus cf. antipathum Steenstrup, 1850

Figs 50, 51, 167, 168

Rhizochilus antipathum Steenstrup, 1850: 75 .

Synonym:

Rhizochilus teramachii Kuroda, 1953: 118 , 125-126, text figs 1, 2.

TYPE MATERIAL. — Rhizochilus antipathum : 7 syntypes ZMUC, one figured by Kosuge & Suzuki (1985: pl. 50, fig. 6) . — Rhizochilus teramachii : holotype TA 1921 , figured by Kosuge & Suzuki (1985: pl. 45, fig. 12) and Higo et al. (2001: 66, G2412s) .

TYPE LOCALITY. — R. antipathum : no locality is given either with the type material (Ole Tendal, pers. comm.)

or in the original description. — R. teramachii : east of Ashizuri-Misaki, Japan, 80-90 fms [146-165 m].

MATERIAL EXAMINED. — New Caledonia proper. 167°07’E, 35-45 m, 1 dd (Fig. 168); stn 1466, 20°46.5’S, EXPÉDITION MONTROUZIER: stn 1321, Secteur de Koumac , 167°06.2’E, 25-45 m, 2 dd (Fig. 51); stn DW1650, 20°54.15’S, 20°44.7’S, 164°14.9’E, 90-115 m, 1 dd; stn 1323, 20°40.9’S, 167°01.7’E, 120-250 m, 1 dd (Fig. 50) .

164°14.8’E, 82-120 m, 1 dd. Futuna. MUSORSTOM 7: stn CP 505, 14°19’S, 178°04’W, 245- Norfolk Ridge. NORFOLK 1: DW 1712, Banc Antigonia, 400 m, 1 dd.

23°23’S, 168°02’E, 180-250 m, 1 dd (Fig. 167). Tonga. BORDAU 2: stn DW 1626, 23°20’S, 176°16’W, 220- Loyalty Islands. Lifou. LIFOU 2000: stn 1462, Baie du Santal, 249 m, 1 dd.

20°47.1’S, 167°03.2’E, 70-120 m, 1 dd; stn 1465, 20°47.7’S,

DISTRIBUTION. — Pacific Ocean : from Kii Peninsula, Japan, “sessile on branches of Antipatharians, in 100-200 m ” (Tsuchiya 2000), “ on Antipathes japonica Brook ” (Higo et al. 1999: 217, G2412), throughout the west Pacific, including Hawaii (on Antipathes grandis: Gage 1962 ; Kay 1979). Present material, shells only in 45-245 m.

REMARKS. — Multispiral protoconch of 3.2-3.3 conical whorls, 760 µm high and 720 µm wide at the base. Protoconch-I of about 1 whorl covered by pustules; protoconch-II of about 2.2 whorls, with 2 spiral keels, sculptured by a series of subsutural prosocline threads and a series of tubercules over each keel; threads tending to fuse at the end of the protoconch giving rise to collabral riblets. Two forms are present in the material examined: one has scaly sculpture over the spiral cords, the other has reduced spiral cords with no scaly sculpture. Colour is variable in both forms, and the larval shells are the same. Further investigation is needed to ascertain the status of the two forms. The publication of Steenstrup (1850) is a summary of a talk given for the members of a scientific society. It states " Rhizochilus antipathum Stp. gen. et sp. nov. ” and the species is described, yet it is clearly indicated that no collection locality was known, not even an ocean. Steenstrup (1853) provided more details. Thus the indication of “Indian Ocean” as type locality, as reported by Higo et al. (1999: 217, G2412), is not justified.