Serrata coriolis, Boyer, 2008

Boyer, Franck, 2008, The genus Serrata Jousseaume, 1875 (Caenogastropoda: Marginellidae) in New Caledonia, Mémoires du Muséum national d'Histoire naturelle 196, pp. 389-436 : 408-409

Serrata coriolis n. sp.

Fig. 26

TYPE MATERIAL. — Holotype (dd) MNHN 20607 .

TYPE LOCALITY. — Loyalty Ridge, 20°35’S, 166°55’E, 470-480 m [BIOGEOCAL: stn DW 307].

MATERIAL EXAMINED. — Loyalty Ridge. BIOGEOCAL: stn DW 307, 20°35’S, 166°55’E, 470-480 m, 1 dd (holotype, Fig. 26).

DISTRIBUTION. — Central Loyalty Ridge , one shell in 470-480 m.

DESCRIPTION. — Shell slender, biconical subcylindrical, solid, opaque. Protoconch damaged. Spire narrow, high, slender, conical, whorls weakly convex. Aperture moderately narrow, vertical, very faintly widening over anterior half. Base rather wide. Outer lip moderately thick, vertical, slightly reflected in central area, shoulder sloping, rounded, middle and lower parts of outer edge very oblique, nearly straight, outer margin rather wide, very thick, slightly carinate, stepped, inner edge slightly sinuous, bearing about 15 tiny, low denticles, smaller than the interspaces. Four very thin, short columellar plaits, rather closely packed over anterior part of columella, 2 lowest ones parallel to each other, very oblique, straight, third one slightly shorter, less oblique, upper one very short, horizontal, with horizontal pleat above.

Colour dirty beige (faded and stained).

Dimensions: 5.00 x 2.00 mm.

Radula unknown.

REMARKS. — Despite the shared biconical shell outline, Serrata coriolis differs from the syntopic smaller species S. lifouana in having a more elongate last whorl, and very thin, short and rather closely packed columellar plaits. Serrata coriolis has a very different shell morphology from those of Serrata species from bathyal depths off the New Caledonia mainland and on the northern Norfolk Ridge. The thickened and centrally reflected labrum distinguishes S. coriolis from Hydroginella species.

ETYMOLOGY. — From the oceanographic vessel Coriolis, which was used for the BIOGEOCAL expedition (1987), during which the type material of Serrata coriolis was collected.