Angustopila antidomedon Pall-Gergely & Hunyadi sp. nov.

Fig. 61

Type material.

Holotype: Vietnam • 1 empty shell (H: 0.94 mm, D: 0.83 mm); Thanh Hóa Province, Như Thanh District, Hải Vân, Hang Lò Cao Kháng Chiến, vicinity of the cave (locality code: 2020/41); 19°37.08'N, 105°34.63'E; 20 m a.s.l.; 14 Feb. 2020; A. Hunyadi leg.; HNHM 105294.

Paratypes: Vietnam • 1 imaged + 8 other shells; same data as for holotype; coll. HA.

Diagnosis.

A medium-sized, conical Angustopila species with a narrow umbilicus, a parietal tooth and a blunt but strong palatal tooth situated at the lower part of the palatal side.

Description.

Shell of normal size for the genus, higher than wide; off-white, conical; body whorl widest from standard apertural view; protoconch consists of 1.25 whorls, with weak spiral striation preceding the first teleoconch whorl; teleoconch with rather strong, irregularly spaced radial growth lines and equally strong, equidistantly and sparsely-arranged spiral striae (ca. 12-19 on body whorl from standard apertural view); whorls 4.5 or slightly less, rounded or very slightly depressed-rounded in form; aperture oblique to shell axis from lateral view; umbilicus narrow; aperture subovoid or reniform with very wide, not distinctly separated sinulus; peristome expanded, not reflected; parietal callus slightly protruding, somewhat detached from penultimate whorl; parietal tooth straight, strong, normally high and long, situated inside shell at some distance from peristome edge; lower palatal tooth, blunt but strong; approximately half of the available shells has a tiny subcolumellar tooth.

Measurements (in mm).

H = 0.86-0.94; D = 0.82-0.88, H/D*100 = 103.6-113.3 (n = 4), RUD = 24.2-25.0 (n = 2).

Differential diagnosis.

Angustopila pustulata sp. nov. is generally larger (wider), although the size ranges slightly overlap (D of A. antidomedon sp. nov.: 0.82-0.88 mm, D of A. pustulata sp. nov.: 0.87-0.93 mm), it has a lower spire (Fig. 77A is a rare example, nearly all shells have a low spire, similar to the holotype), and its palatal tooth is much lower (weaker). Moreover, some shells of A. antidomedon sp. nov. possess a small columellar tooth. Angustopila occidentalis sp. nov. is larger, has a lower spire and a comparatively larger aperture with usually weaker palatal tooth. Angustopila uvula sp. nov. has a concave-conical shell and a stronger parietal lamella. See also under A. bathyodon sp. nov. and A. gracilis sp. nov.

Etymology.

From the Greek ἀντιδομή (= opposed) and ὀδούς (= tooth) referring to the position of the palatal tooth in relation to the parietal tooth.

Distribution.

This species is known from the type locality only (Fig. 27).