Pincerna mouhoti (L. Pfeiffer, 1862)

Sang, Do Duc & Son, Nguyen Thanh, 2022, The land snail genus Pincerna Preston, 1907 (Gastropoda: Alycaeidae) from Vietnam and Laos, with description of a new species, Raffles Bulletin of Zoology 70, pp. 364-375 : 369

Pincerna mouhoti (L. Pfeiffer, 1862)

( Figs. 1 , 2B, C , 6B ; Tables 1, 2)

Alycaeus mouhoti L. Pfeiffer, 1863a (1862) : 275, pl. 36, figs. 1, 2. (type locality: Lao Mountains , Laos).

Alycaeus mouhoti – L. Pfeiffer, 1863b: 228, 229, pl. 59, figs. 9–11; von Martens, 1867: 67; Reeve, 1878: pl. 3, species 19; Fischer, 1891: 108; Fischer & Dautzenberg, 1904: 432; Páll-Gergely et al., 2017: 10; Inkhavilay et al., 2019: 12 , figs. 4A, B.

Alycaeus (Orthalycaeus) mouhoti – Kobelt & Möllendorff, 1897: 147; Ancey, 1898: 138.

Alycaeus (Alycaeus) mouhoti – Kobelt, 1902: 347; Saurin, 1953: 113.

Pincerna mouhoti – Páll-Gergely et al., 2020: 180.

Types examined. Lao Mountains , leg. Mouhot, NHMUK 20170120 (syntypes) ( Figs. 2C , 6B ) .

Additional material examined. ZMHU/ 7 , Vietnam, Hòa Bình Province, Mai Châu District, Hang Kia - Pà Cò Nature Reserve, near the road No. 6, between Hòa Bình and SƠn La, under rocks in primary forest, 20°45′47″N, 104°52′26″E, 829 m a.s.l., col. D.S. Do, 03 September 2017 ; ZMHU/ 8 , Vietnam, SƠn La Province, Vân Hồ District, Vân Hồ Commune , Pa Cốp Village , densely vegetated limestone hill, 21°45′56″N, 104°44′30″E, 1013 m a.s.l., col. D.S. Do & V. T. Sin , 26 October 2013 ; ZMHU/ 7 ( Fig. 2B ), Vietnam, SƠn La Province , MƯ ờng La District , MƯ ờng Bú Commune, entrance of the Thẳm Bó Cave , limestone slope with woody regrowth, 21°24′05″N, 104°06′13″E, 715 m a.s.l., col. D.S. Do & T.L. Nguyen , 27 October 2012 ; ZMHU/ 2 , Vietnam, SƠn La Province, Phù Yên District , MƯ ờng Do Commune, Lằn Village , steep limestone cliff, woody regrowth at foot, 21°11′46″N, 104°47′06″E, 674 m a.s.l., col. D.S. Do, 12 July 2014 ; ZMHU/ 3 , Vietnam, SƠn La Province, Thu ận Châu District, Co Mạ Commune , Copia Nature Reserve , steep limestone slope with dense disturbed vegetation, 21°21′26″N, 103°31′18″E, 1246 m a.s.l., col. D.S. Do & T.H. Nguyen , 08 June 2013 ; ZMHU/ 2 , Vietnam, SƠn La Province, Yên Châu District, Yên SƠn Commune , Chi Đảy Cave , primary forest on limestone, 21°08′30″N, 104°10′29″E, 815 m a.s.l., col. D.S. Do & X.H. Nguyen, 02 September 2017 .

Diagnosis. Pincerna mouhoti is characterised by a mediumsized, translucent shell with rather regular ribs on R1, R2 long, smooth, slender and equal-spaced ribs and open umbilicus.

Distribution. Pincerna mouhoti is known from Laos (Luang Phrabang Province) and Vietnam (SƠn La and Hòa Bình Provinces) ( Fischer, 1891; Saurin, 1953; Inkhavilay et al., 2019; this study).

Remarks. Figure 4E in Inkhavilay et al. (2019) shows that the shell surface is smooth, R2 long and smooth, and therefore it may belong to P. mouhoti .

Figures

Fig. 1. Distribution of Pincerna species in Vietnam and Laos. Triangle: Pincerna anceyi; Grey circle: Pincerna costulosus; Black circles: Pincerna mouhoti; Squares: Pincerna vanbuensis; Star: Pincerna clausa, new species. The localities are detailed in Table 1.

Fig. 2. Shells (apertural view, dorsal view, ventral view, and side view) of Pincerna species. A, Pincerna anceyi (Mabille, 1887), syntype MNHN-IM-2000-31797; B, C, Pincerna mouhoti (L. Pfeiffer, 1862): B, specimen from MƯờng La, SƠn La, Vietnam, ZMHU; C, syntype NHMUK 20170120; D, E, Pincerna costulosus Bavay & Dautzenberg, 1912: D, syntype MNHN-IM-2000-31786; E, specimen from Phong Thổ, Lai Châu, Vietnam, ZMHU.

Fig. 6. Synoptic view of Vietnamese and Laos Pincerna species. A, MNHN-IM-2000-31797; B, NHMUK 20170120; C, MNHN- IM-2000-31786; D, VNMN-IZ 002.304; E, MNHN-IM-2000-31798.

Fig. 4. Shell (apertural view, dorsal view, ventral view, and side view) of Pincerna clausa, new species. A, holotype VNMN-IZ 002.304; B, C, paratypes ZMHU. MOL 044.