Babelomurex natalabies, Oliverio, 2008

Oliverio, Marco, 2008, Coralliophilinae (Neogastropoda: Muricidae) from the southwest Pacific, Mémoires du Muséum national d'Histoire naturelle 196, pp. 481-586 : 534

Babelomurex natalabies n. sp.

Figs 77, 219, 220

TYPE MATERIAL. — Holotype (dd) MNHN 20841 .

TYPE LOCALITY. — Norfolk Ridge , 23°20’S, 168°03’E, 311 m [CHALCAL 2: stn DW 81] .

MATERIAL EXAMINED. — Norfolk Ridge. CHALCAL 2: stn DW 81, 23°20’S, 168°03’E, 311 m, 1 dd (holotype, Fig. 77) .

DISTRIBUTION. — Known only from Norfolk Ridge , in 311 m.

DESCRIPTION. — Shell small for the genus, height 16.4 mm, width 21.9 mm, not thick, rhomboidal in shape.

Protoconch multispiral, partly eroded, of 2+ conical whorls, 640+ Μm high, 770 Μm wide at base.

Teleoconch of 5 whorls, last whorl about 70% of total height. Spire high, conical, with flat or slightly convex sides well angled at the periphery. Suture incised. Last whorl 2/3 of total shell height, constricted at the base. Aperture moderately large (8.3 mm high and 5.5 mm wide), semicircular. Outer lip with finely crenulated edge, internally lirate, angled at the shoulder, usually continuous at peripheral spines; inner lip almost straight, extending into a sharply detached callus. Siphonal canal moderately long, sharply curved dorsally and usually gently curved to the right; umbilicus deep and narrowly perforated. Teleoconch axial sculpture of prosocline axial ribs; 8 ribs on last whorl, 7-9 ribs on the first whorls. A single row of scabrous spines at about half the height of the spire (suprasutural on first whorls), each corresponding to one axial rib on the body whorl and consisting of long and narrow folded laminae, with the open side toward the aperture. Spiral sculpture below the spine row on the last whorl, of 7-10 densely packed spiral cords, with finely imbricate scaly spines; sutural ramp without an obvious spiral sculpture; fasciole bearing sharp scaly projections. Microsculpture of irregular growth lines and of minute spiral threads. Ground colour whitish to yellowish, with pinkish blurring in the interspaces.

REMARKS. — Babelomurex natalabies n. sp. is similar to B. virginiae in the general outline, the single row of peripheral spines and the base sculptured by scaly spiral cords. It differs in the lighter shell and the absence of obvious spiral sculpture on the sutural ramp. With B. fruticosus ( Kosuge, 1979) , it shares a smooth sutural ramp but differs in the presence of imbricate scaly spines on the base and the lack of a second abapical major cord. An additional specimen from a dealer (Norfolk Ridge, 250 m depth) has been examined. From the very variable B. spinosus (Hirase, 1908) it differs in having a single row of spines and more scabrous spiral cords covering the base. The species in the group of B. diadema (A. Adams, 1854) differ from B. natalabies n. sp. in having additional rows of spines and in their broader peripheral spines.

ETYMOLOGY. —The specific epithet natalabies refers to the shape of the shell, which resembles a Christmas tree (natal, Latin, adjective = of birth, natal, i.e. Christmas; abies, Latin, noun = fir tree; noun in apposition).