Tonkinospira pauperrima (Bavay & Dautzenberg, 1909)

Páll-Gergely, Barna, Grego, Jozef, Vermeulen, Jaap J., Reischütz, Alexander, Hunyadi, András & Jochum, Adrienne, 2019, New Tonkinospira Jochum, Slapnik & Páll-Gergely, 2014 species from Laos and Vietnam (Gastropoda: Pulmonata: Hypselostomatidae), Raffles Bulletin of Zoology 67, pp. 517-535 : 527

Tonkinospira pauperrima (Bavay & Dautzenberg, 1909)

( Fig. 8 )

Helix (Systenostoma) pauperrima Bavay & Dautzenberg, 1909a: 243–244 . (type locality: Phu-Quoc-Oai [see remarks])

Helix (Systenostoma) pauperrima — Bavay & Dautzenberg, 1909b: 195–196, pl. 8, figs 4–6.

Systenostoma pauperrima — Pilsbry, 1917: 225–226, pl. 38, figs 3–5.

Systenostoma pauperrima — Schileyko, 1998b: 165, fig. 202.

Tonkinospira pauperrima — Jochum et al., 2014: 32–36 , fig. 2.

Types examined. 1 shell, syntype (H: 1.6 mm, D: 1.44 mm, Fig. 8 .) (MNHN-IM-2000-32864), Phu-Quoc-Oaï, coll. Demange.

Additional material examined. Vietnam, Quang Ninh Prov., Ha Long Bay, Cap La Cave , deposit of soil fallen in through roof in pristine cave, vegetation outside cave high and woody, 20°51.793′N, 107°13.541′E, leg. J.J. Vermeulen & K. Anker, 07 March 2018, JJV 17630/197 shells + 4 separated shells (identified as Tonkinospira cf. pauperrima ) .

Diagnosis. A medium sized Tonkinospira species with a high conic shell, rounded/parabolic body whorl, dense spiral striation, and a peristome that is not adnate to penultimate whorl.

Description. Shell medium sized for the genus; high conical with rounded (rather parabolic) body whorl; 5 whorls, regularly increasing; suture deep; penultimate whorl widest from standard apertural view; protoconch consists of almost 1.5 whorls, finely rugose, and densely, strongly spirally striated; teleoconch with irregular, rough radial growth lines, and dense, rather regular spiral striation creating a reticulate surface texture, ca. 24 in number in the middle shell line from apertural view; aperture strongly oblique to shell axis, turning downward in alignment with the penultimate whorl in lateral view; aperture ovate-subquadrate; peristome slightly expanded, not reflected; aperture not adnate to penultimate whorl; umbilicus narrow, partly covered by peristome and is almost ½ the diameter of the base of the shell.

Differential diagnosis. See under Tonkinospira danangensis and T. raxajacki new species.

Remarks. The type locality, “Phu-Quoc-Oaï” (Quốc Oai; Phu is an old way to call a ward) is a district approximately 20 km west from the city centre of Hanoi. This must not be mistaken with Phú Quốc Island in southern Vietnam.

The newly-collected sample ( JJV 17630) contains shells of variable shell characters such as shell height and shell width. Although the shells are generally smaller than the syntype of T. pauperrima , and the whorls are more accurately rounded, these differences are better explained as intraspecific variability .

Figures

Fig. 8. Tonkinospira pauperrima (Bavay & Dautzenberg, 1909), MNHN-IM-2000-32864 (syntype).