Serrata fusulina, 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 : 405

Serrata fusulina n. sp.

Fig. 23

TYPE MATERIAL. — Holotype (dd) MNHN 20602 .

TYPE LOCALITY. — Southern New Caledonia, 23°10’S, 167°10’E, 675-680 m [BIOCAL: stn DW 33] .

MATERIAL EXAMINED. — Southern New Caledonia. BIOCAL: stn DW 33, 23°10’S, 167°10’E, 675-680 m, 1 dd (holotype, Fig. 23) .

DISTRIBUTION. — Southern New Caledonia, one shell from 675-680 m.

DESCRIPTION. — Shell biconical fusiform, solid, opaque. Protoconch paucispiral, large, wide, dome-shaped, smooth. Spire tall, subconical, apex blunt, whorls flat. Aperture very narrow, very oblique, widening weakly towards base. Base moderately tapering. Outer lip moderately thickened, subvertical, slightly reflected, narrowing towards base. Shoulder sloping, weakly delineated, slightly rounded, outline making very faint angle below shoulder, straight and very oblique over its anterior half, outer margin rather wide, moderately thickened, bevelled, weakly stepped, inner lip vertical, straight, bearing 11 very small, subequal denticles, lowest ones larger than others. Four columellar plaits, 2 anterior ones moderately thickened, oblique, sinuous, 2 posterior ones finer, less oblique, decreasing in size posteriorly.

Ground colour whitish (faded).

Dimensions: 4.50 x 2.05 mm.

Radula unknown.

REMARKS. — Serrata fusulina differs from S. minima principally in its narrower and more fusiform shell outline, its taller and more produced spire, its more oblique columellar plaits, its shorter aperture and its less shouldered outer lip.

ETYMOLOGY. — Latin fusulus (n., with the shape of a spindle) and -ina (diminutive), referring to the resemblance of the shell outline to a small spindle, in the same way as the shell of the species belonging to the foraminiferan genus Fusulina does.