Bouchetcamaena fusca Pall-Gergely, 2022

Pall-Gergely, Barna, Ablett, Jonathan D., Szabo, Marton & Neubert, Eike, 2022, Revision of the " Chloritis delibrata (Benson, 1836) " group (Gastropoda, Stylommatophora, Camaenidae), ZooKeys 1086, pp. 1-31 : 1

Bouchetcamaena fusca Pall-Gergely sp. nov.

Figure 12

Type material.

Holotype: Munipur [India, Manipur], coll. Godwin-Austen, NHMUK 1903.7.1.391/2 (D: 16.8 mm, H: 8 mm, mixed lot with B. delibrata , NHMUK 1903.7.1.391/1).

Paratypes: same data as holotype, NHMUK 1903.7.1.391/3 (1 shell: paratype); Gaziphima, Naga Hills, Munipur frontier line, coll. Godwin-Austen, NHMUK 1903.7.1.385 (2 paratypes); Khasi Hills, coll. Godwin-Austen, no. 183, NHMUK 1903.7.1.381a/2 (1 shell, mixed lot with B. delibrata , NHMUK 1903.7.1.381a/1); Manipur, coll. Godwin-Austen, NHMUK 20191134 (1 shell).

Diagnosis.

Shell small to medium-sized, with flat dorsal side or very slightly elevated spire; thick, brown, matt periostracum makes hair scars practically invisible, aperture oval.

Description.

Shell small to medium-sized; depressed-globular, dorsal side flat or spire very slightly elevated; body whorl slightly or relatively strongly but bluntly shouldered; colour brownish due to thick, matt periostracum; protoconch consists of 1.5 whorls, finely wrinkled, with short hairs near suture; in some specimens wrinkles only visible in the middle of whorls, whereas in others hair scars (pits) are also discernible; entire shell consisting of 3.75-4 whorls, suture moderately deep; short hairs visible in the suture and inside umbilicus; hair scars practically invisible due to thick periostracum; in one paratype (NHMUK 1903.7.1.391) periostracum of lighter colour around each hair scar on the ventral side, making the density of scars visible; very few hair scars visible at the parietal callus, but to a much lesser degree than in other species; aperture oval/subrectangular; peristome expanded and slightly reflected in direction of umbilicus; palatal part with a very thin, whitish, semi-transparent layer; hair scars not visible beneath parietal callus; umbilicus open, relatively narrow, peri-umbilical keel only very slightly indicated.

Measurements.

D = 15.3-18.7 mm, H = 7.8-8.8 mm (n = 5).

Differential diagnosis.

Bouchetcamaena raripila sp. nov. is most similar to B. fusca sp. nov. in having a relatively small shell, narrow umbilicus and brown periostracum, but it differs in the strong, sparsely standing hair scars. All other Bouchetcamaena species have larger, lighter-coloured shells and a wider umbilicus.

Etymology.

The new species is named after its dark (fuscus in Latin) periostracum.

Distribution.

Seems to be restricted to Manipur, the Khasi and the Naga Hills (India).

Figures

Figure 6. Positions of close-up images. Abbreviations: CA: callus; DM: middle of dorsal side; LV: last whorl; PC: protoconch. Not to scale.

Figure 12. Bouchetcamaena fusca Pall-Gergely sp. nov., holotype (NHMUK 1903.7.1.391 / 2). For positions of close-up images see Fig. 6 (F = DM, G = CA, H: LV, I: PC).