Angustopila vandevenderi Pall-Gergely & Jochum, 2023

Pall-Gergely, Barna, Hunyadi, Andras, Vermeulen, Jaap J., Grego, Jozef, Sutcharit, Chirasak, Reischuetz, Alexander, Dumrongrojwattana, Pongrat, Botta-Dukat, Zoltan, Oerstan, Aydin, Fekete, Judit & Jochum, Adrienne, 2023, Five times over: 42 new Angustopila species highlight Southeast Asia's rich biodiversity (Gastropoda, Stylommatophora, Hypselostomatidae), ZooKeys 1147, pp. 1-177 : 1

Angustopila vandevenderi Pall-Gergely & Jochum sp. nov.

Fig. 58

Type material.

Holotype: Vietnam • 1 empty shell (H: 0.8 mm, D: 0.74 mm); Cuc Phuong National Park; 20°17.80'N, 105°39.66'E; 14-16 May 2008; W. van Devender leg.; VNMN-IZ 000.002.301.

Paratype: Vietnam • 1 shell; same data as for holotype; VNMN-IZ 000.002.302.

Additional material.

Vietnam • 1 j/b shell; same data as for holotype; VNMN-IZ 000.002.303.

Diagnosis.

A small Angustopila species with a conical-globular shell, few (ca. 3.75) whorls, normally developed spiral striation and a parietal tooth.

Description.

Shell small for the genus, slightly higher than wide; conical-globular; body whorl widest in standard apertural view; protoconch consists of 1.5 whorls with weak spiral striation preceding the first teleoconch whorl; teleoconch with very fine irregularly spaced, weak radial growth lines crossed by much stronger rather regularly and sparsely-spaced spiral striae (ca. 11 or 12 on body whorl from apertural view); on both ventral and dorsal surfaces of body whorl, spiral lines dominate or some radial lines are of comparable strength; whorls ca. 3.75, rounded; aperture very slightly oblique to shell axis from lateral view; umbilicus moderately wide; aperture ovate-oblong, parietal callus convex; sinulus very wide, weakly isolated due to the rather thick and deeply extending parietal tooth; peristome expanded, not reflected; parietal callus only very slightly detached from penultimate whorl; parietal tooth moderately elevated, of normal length, reaches parietal callus, perpendicular to parietal wall.

Measurements (in mm).

H = 0.79-0.8, D = 0.74, H/D*100 = 106.8-108.1, RUD = 26.7-29.5 (n = 2).

Differential diagnosis.

Angustopila vandevenderi sp. nov. is smaller than shells of the surrounding known populations of A. fabella , has a conical-globular (instead of a conical or concave-conical) shell, and a stronger parietal tooth. Angustopila margaritarion sp. nov. is also similar to this new species in terms of shell size and shape. However, A. vandevenderi sp. nov. has stronger spiral striation ( A. margaritarion sp. nov. is practically smooth, glossy), and has a lower, more slender parietal tooth (more elevated and club-shaped in A. margaritarion sp. nov.).

Etymology.

This new species is dedicated to and named after Robert Wayne Van Devender, who collected the shells.

Distribution.

This new species is known only from its type locality in the Cuc Phuong National Park, northern Vietnam (Fig. 27 ).

Remarks.

A juvenile shell of possible A. fabella was found together with the two shells of A. vandevenderi sp. nov. If the identification of that shell is correct, it would mean that the two species live syntopically, and are thus, distinct biological species.

Figures

Figure 27. Distribution of Angustopila species.

Figure 58. Angustopila vandevenderi Pall-Gergely & Jochum, sp. nov. (holotype, VNMN-IZ 000.002.301). Apertural (A), lateral (B), ventral (C) and apical (D) sides of the shell; aperture (E), microstructure of the protoconch (F), ventral (G) and frontal (H) surface of the body whorl.