Bouchetcamaena subdelibrata 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 subdelibrata Pall-Gergely sp. nov.

Figure 17

Type material.

Holotype: S. Silhet, leg. Chennell, coll. Godwin-Austen, NHMUK 20191132/1 (D: 17.7 mm, 8.6 mm).

Paratypes: Same data as holotype, NHMUK 20191132/2 (1 paratype); Habiang, Garo Hills, coll. Godwin-Austen 183, ex coll. W. Blanford, NHMUK 1906.1.1.714 (3 paratypes); South Sylhet Hills, coll. W Chennell, NHMUK 1903.7.1.61/2 (1 paratype, mixed lot with B. delibrata : NHMUK 1903.7.1.61/1).

Additional material examined.

Same data as holotype, NHMUK 20191132/3 (7 juvenile shells) .

Diagnosis.

Shell medium-sized, nearly flat, greenish, glossy, entire shell with densely arranged hair scars (mostly hardly visible), aperture oval, peristome not particularly expanded.

Description.

Shell medium-sized, rather thin walled; depressed, dorsal side entirely flat (type series), or slightly elevated (Habiang); colour greenish to dark yellowish with an obscure, reddish band just above the blunt keel; protoconch consisting of 1.5 whorls, with densely arranged, clearly visible, knob-like hair scars; entire shell with 3.50-3.75 whorls; separated by a rather deep suture; teleoconch overall glossy, with irregular, fine growth lines, ventral side and edge of body whorl (except for last quarter whorl) covered with densely-arranged hair scars, some hair scars also recognizable on the last quarter whorl, but not regular as on the preceding areas; last whorl of dorsal side dominated by wrinkles, and regular hair scars only visible in areas before the last half whorl; aperture almost rounded, slightly oval; peristome strongly expanded and slightly reflected in direction of umbilicus; palatal part with a very thin, whitish, semi-transparent layer, which allows hair scars on penultimate whorl to be seen; umbilicus open, normally wide, funnel-shaped, peri-umbilical keel blunt, only very slightly indicated.

Measurements.

D = 17.7-19.3 mm, H = 8.6-9.9 mm (n = 4).

Differential diagnosis.

Bouchetcamaena delibrata is most similar to the new species, but it is larger, has a more strongly depressed shell, elongated aperture and expanded peristome, and lacks hair scars on the last half whorl. The hair scars of B. delibrata are more widely-spaced than those of B. subdelibrata sp. nov.

Etymology.

The specific epithet refers to the most similar species.

Distribution.

The new species is known from the Garo Hills (Meghalaya, India), and the neighbouring Silhet Hills to the south.

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 17. Bouchetcamaena subdelibrata Pall-Gergely sp. nov., holotype (NHMUK 20191132). For positions of close-up images see Fig. 6 (F = DM, G = CA, H: LV, I: PC).