Parvidontia laevis n. sp.

(Figs 38; 39A)

TYPE MATERIAL. — Holotype: 1 LV, L 5.8 mm, H 5.5 mm, T 1.8 mm (MNHN).

Paratypes: New Caledonia, secteur de Canala, stn 729, coarse shell sand, 21°19’S, 165°54’E, 42-45 m, 2 LV,1 RV, L 6.5 mm, H 5.7 mm, T 1.9 mm; L 5.8 mm, H 1.5 mm; L 3.2 mm, H 3.0 mm (MNHN). — New Caledonia, Secteur de Belep, stn 1196, 19°33’S, 163°21’E, 30 m, 1 LV, L 10.7 mm, H 10.9 mm, T 3.4 mm (BMNH 20050578) .

TYPE LOCALITY. — New Caledonia, Touho, stn 1260, 20°44’S, 165°14’E, shell sand, 49-59 m.

ETYMOLOGY. — Latin laevis, smooth.

MATERIAL EXAMINED. — Touho. 1 stn, 49-59 m, 1 v.

DESCRIPTION

Small, H to 10.9 mm, L to 10.7 mm, thin-shelled, subcircular, umbones prominent, external surface smooth, except for fine commarginal threads. Protoconch large, 210 µm, smooth, with a few marginal growth increments. Ligament external, very short. Hinge narrow, teeth small,LV with two cardinal teeth of which anterior is larger and projecting; RV with 2 cardinals of which anterior is very small. Lateral teeth absent. Anterior adductor muscle scar narrow, detached for 1/2 length.Pallial line entire, broad, with dorsal extensions. Inner shell margin smooth.

REMARKS

Externally, the smooth shell, with low commarginal lamellae, of P. laevis n. sp. resembles Leucosphaera diaphana n. sp. (p. 118) but it can easily be distinguished by the presence of cardinal teeth.