Diancta controversa, 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 : 11-13

Taxon classification Animalia Mesogastropoda Diplommatinidae

Diancta controversa sp. n. Figs 21-23

Type material.

Holotype MNHN IM-2000-27418, paratypes MNHN/8 IM-2000-27419, NMBE 516874/2. Type locality: Viti Levu, Wailotua karst, 50-80 m, rainforest, -17.7582 178.4166, leg. Bouchet, 25-27.08.1998.

Material.

Viti Levu, Waivisa karst, 50-80 m, rainforest, -17.6879 178.4033, leg. Bouchet, 27.08.1998, MNHN/5; Viti Levu, Nakorosule limestone outcrop, 30 m, degraded forest, -17.7734 178.2517, leg. Bouchet & Dayrat, 16.02.1999, MNHN/1; Viti Levu, Saweni karst, 50-60 m, dry forest, -17.9032 177.7983, leg. Bouchet, 22.08.1998, MNHN/1.

Etymology.

Latin adjective controversus, -a, -um = coiling in the opposite direction.

Diagnosis.

Shell dextral, reddish to pinkish, regularly spaced ribs, last whorl slightly ascending, aperture connected to the last whorl, columellar plate with a strong inner plate, opposite a strong axial palatalis.

Description.

Shell dextral, oval, medium sized, reddish to pinkish coloured; last whorl constricted; protoconch broad, obtuse; umbilicus slit-like, concave periomphalum; teleoconch sculpture of regularly spaced fine ribs, ribs become somewhat coarser on the last whorl; last whorl slightly ascending; aperture subrectangular, peristome funnel-shaped, doubled; aperture connected to the last whorl with a slight labial callus; no visible pleats in the aperture; inside, columellar plate with a strong inner plate, outer plate less developed, and a basal knob opposite to the inner plate with a strong axial palatalis.

Operculum corneous, flat, internally with a short apophysis, DO = 0.54.

Measurements.

Holotype (Fig. 21): H = 3.2; D = 2.47; PH = 1.53; PD = 1.55; W = 5.5.

Distribution

(Fig. 170). Central to eastern Viti Levu.

Remarks.

For a differential diagnosis, refer to Diancta dextra sp. n., the only other dextral species of Diancta species so far known in Fiji. Apart from the coiling direction, Diancta controversa sp. n. resembles Diancta martensi in its aperture, which is attached to the last whorl. Both share a similar axial palatalis, but the columellar plate in Diancta martensi is not subdivided in two parts of differing size and shape.