Vargapupa humilis Páll-Gergely, 2016, n. sp.

Vargapupa humilis n. sp.

Figures 3 A–I.

Material examined. Holotype (one empty shell, MNHN IM- 2012-27159, Figs 3 A–E), paratype (one empty shell with broken apex, MNHN 2012-27160, Figs 3 F–I), and one non-type (one juvenile empty shell, MNHN IM- 2012-27161). Central Laos, Luang Prabang province, just NE of Phou Khoun, under rocks in old secondary forest above large cave, 1177 m a.s.l., 19°26.784'N, 102°26.290'E, leg. Ahmed Abdou & Igor V. Muratov, 15.11.2006. (locality code: 32L06).

Etymology. The species epithet humilis (Latin: low, small, slight) refers to the basal keel, which is weaker than in the other two Vargapupa species.

Diagnosis. A Vargapupa species with rather spindle-shaped shell, nearly rounded aperture and low basal keel.

Description. Shell rather spindle shaped, light brownish-greyish, with 9 regularly increasing, moderately bulging whorls; protoconch of slightly less than one whorl, very finely granulated, not glossy, without radial sculpture; teleoconch with regular, strong but blunt ribs without spiral striation; ribs lacking on neck region above keel (this area is irregularly, finely wrinkled), but 4 to 5 rather regular ribs present behind peristome; ribs stronger between keel and umbilicus than elsewhere; basal keel blunt, low, starts one half whorl before the aperture, above umbilicus, and ends just a bit before the peristome; groove corresponding to keel inside aperture absent; ribs present on keel, especially in the paratype (Fig. 3 H); the white line visible above keel of the holotype (Fig 3 E) is not a thickening of inner shell surface; aperture nearly rounded, palatal-parietal transition angled, columellar-parietal transition not angled; peristome slightly oblique from lateral view (Figs 3 C, I); parietal callus well developed; apertural rim lighter colour than rest of shell, thickened and slightly reflexed, especially in the direction of the umbilicus; umbilicus very slightly open, slit-like.

Measurements of the holotype. H: 8.55 mm, W: 3.0 mm. The other two examined shells are broken.

Remarks. Vargapupa oharai is much larger, possesses a very strong main basal keel and a weaker additional one, has a channel in the basal part of the aperture corresponding with the main keel, a nearly rectangular aperture, and a less oblique peristome (from lateral view). Vargapupa biheli Páll-Gergely, 2015 possesses a single basal keel that is much stronger than that of the new species, and has a slender triangular shell, which is rather spindle-shaped in V. humilis n. sp. Moreover, similarly to V. oharai, V. biheli also has a less oblique peristome, a slight apertural basal channel corresponding with the keel, and a somewhat rectangular aperture.

Distribution. Vargapupa humilis n. sp. is known from the type locality only.