Moussonia vitianoides, Neubert, Eike & Bouchet, Philippe, 2015

Neubert, Eike & Bouchet, Philippe, 2015, The Diplommatinidae of Fiji - a hotspot of Pacific land snail biodiversity (Caenogastropoda, Cyclophoroidea), ZooKeys 487, pp. 1-85 : 34

Taxon classification Animalia Mesogastropoda Diplommatinidae

Moussonia vitianoides sp. n. Figs 69-71

Type material.

Holotype MNHN IM-2000-27451, paratypes MNHN/127 IM-2000-27452, NMBE 516857/20. Type locality: Viti Levu, Nakorosule limestone outcrop, 30 m, degraded forest, -17.7734 178.2517, leg. Bouchet & Dayrat, 16.02.1999.

Material.

Fiji, Viti Levu, Waivisa karst, 50 m, in washings from karstic spring, -17.6879 178.4033, leg. Bouchet, 27.08.1998, MNHN/25, NMBE 516904/5; Viti Levu, Waivisa Karst, 50-80 m, rainforest, -17.6879 178.4033, leg. Bouchet, 27.08.1998, MNHN/58, NMBE 516892/7.

Etymology.

Vitiana and suffix -oides, meaning similar to Moussonia vitiana .

Diagnosis.

Shell dextral, yellow brownish, teleoconch with bluntly keeled whorls, densely spaced ribs, both parietal lamellae simple, two palatal lamellae, first palatalis above aperture, second palatalis above angular edge of peristome.

Description.

Shell dextral, small, last whorl almost not constricted, yellow brownish; protoconch of 2 whorls, smooth; teleoconch of> 5 bluntly keeled whorls, sculpture of strong, densely spaced ribs; suture deep; last whorl slightly ascending before aperture; umbilicus, slit-like open; aperture attached to last whorl, subrectangular, peristomial rim doubled, reinforced by a strong labial callus, columellar side with a strong columellaris; internal lamellar system with 1 columellaris, two parietal and two palatal lamellae; columellaris a thin lamella, with a strong undulation at its end above the aperture; inner parietalis a long lamella, which increases in height towards its end, shortly overlapping with the outer parietalis, which is a low lamella; first palatalis a fine elongate lamella above the aperture, the second palatalis deep inside the shell above the angular edge of the peristome forming a strong almost axially orientated lamella running from the palatum to the inner basal surface of the whorl, corresponding to a small sutural furrow on the outer side of the shell.

Operculum unknown.

Measurements.

Holotype (Fig. 69): H = 1.98; D = 1.14; PH = 0.67; PD = 0.68; W = 6.5.

Distribution

(Fig. 170). Two karstic outcrops in eastern central Viti Levu.

Remarks.

The first palatalis is not present in all specimens. Moussonia vitianoides sp. n. can superficially be confused with Moussonia vitiana . It differs from it by the presence of two palatal lamellae, with the second one in an almost axial position. This remarkable feature can also be observed in Moussonia uncinata sp. n., but the latter has a larger, deep brown shell, and lacks the first palatalis.