Amphidromus (Amphidromus) pervariabilis Bavay & Dautzenberg 1909
Creators: name: Inkhavilay, Khamla
name: Sutcharit, Chirasak
name: Panha, Somsak
Publisher: name: Zenodo
Year: 2017
Subjects: Biodiversity
Taxonomy
Animalia
Mollusca
Gastropoda
Stylommatophora
Camaenidae
Amphidromus
Amphidromus pervariabilis

description: Amphidromus (Amphidromus) pervariabilis Bavay & Dautzenberg, 1909 Figs 1, 5 A−L; Table 1
Amphidromus pervariabilis Bavay & Dautzenberg, 1909b: 246-247. Type locality: Ban-Lao, Muong- Kong, Pha-Long, Pac Kha.
Amphidronus pervariabilis – Bavay & Dautzenberg 1909a: 279-281, pl. 9, figs 1–10, pl. 10, figs 1–8. — Laidlaw & Solem 1961: 527, 528. — Richardson 1985: 15.
Material examined
Type material
VIETNAM: 2 shells (Fig. 5 A–B), syntypes of A. pervariabilis s.str. MNHM-IM- 2000-2049, from Ban- Lao [19° 39′ N, 103° 19′ E], Muong-Kong [19° 33′ N, 104° 44′ E], Pha-Long [22° 48′ N, 104° 14′ E], Pac Kha [21° 00′ N, 104° 35′ E].
VIETNAM: 2 shells (Fig. 5C), syntypes of A. pervariabilis var. “ bifasciata ”, from Ban-Lao, Muong- Kong, Pha-Long, Pac Kha (MNHM-IM- 2000-2059).
VIETNAM: 1 shell (Fig. 5D), syntype of A. pervariabilis var. “ goniostoma ”, from Phong-Tho, 22°34′ N, 103°22′ E (MNHM-IM- 2000-2058).
VIETNAM: 2 shells (Fig. 5E), syntypes of A. pervariabilis var. “ lilacina ”, from Ban-Lao (MNHM- IM- 2000-2052).
VIETNAM: 1 shell (Fig. 5F), syntype of A. pervariabilis var. “ minor ”, from unknown locality (MNHM- IM-2000-2050).
VIETNAM: 2 shells (Fig. 5G), syntypes of A. pervariabilis var. “ monozonalis ”, from Ban-Lao (MNHM- IM- 2000-2057).
VIETNAM: 1 shell (Fig. 5H), syntype of A. pervariabilis var. “ obesa ”, from Muong-Bo, 22°24′ N, 102°49′ E (MNHM-IM- 2000-2053).
VIETNAM: 1 shell (Fig. 5I), syntype of A. pervariabilis var. “ protracta ”, from Ban-Lao, Muong-Kong, Pha-Long, Pac Kha (MNHM-IM- 2000-2051).
VIETNAM: 2 shells (Fig. 5J), syntypes of A. pervariabilis var. “ tricolor ”, from Ban-Lao (MNHM- IM- 2000-2054).
Other material
LAOS: 3 shells (Fig. 5 K–L), Km 34, road to Ban Namly, Khua District, Phongsaly, 21°11′55.5″ N, 102°6′40.2″ E, 834 m amsl (CUMZ 7014).
Description
Shell chirally dimorphic, elongate conical, rather thick and glossy. Spire elongate conical; apex acute, with or without black spot on tip. Whorls 6 to 7 convex to smooth; suture wide and shallow; last whorl rounded to well rounded. Periostracum thin corneous; varix usually absent. Shell color varies from uniform white, yellowish to reddish brown or with narrow to wide brownish peripheral and umbilical bands. Parietal callus thin and transparent. Aperture ovate to oblique elongated; peristome expanded and not reflected; lip white, brownish or purplish. Columella straight, thick or thin and white or brownish. Umbilicus imperforated.
Remarks
This species tend to have a high diversity of shell colors, with eight infra-specific names being provisionally proposed to distinguish the distinct shell shape and color patterns. We examined all the type specimens and recognized them as subspecific entities of one species.
Laidlaw & Solem (1961) recognized this species as a synonym of A. dautzenbergi Fulton, 1899. The latter species exhibits a thin shell, yellowish with a thin faded greenish streak near the umbilicus, a white subsutural band and an elongated ovate aperture, while A. pervariabilis has a thick shell, monochrome or with dark brown spiral band and ovate aperture. However, the type locality of A. dautzenbergi was “ Tonkin ”, the historical political division during the French colonial period, and it still is an uncertain boundary. The species is known from the holotype only (Sutcharit et al. 2015: fig. 6g), no specimen was found in the present study, and, therefore, the taxonomic status of A. dautzenbergi and A. pervariabilis remains to be confirmed.
description: Published as part of Inkhavilay, Khamla, Sutcharit, Chirasak & Panha, Somsak, 2017, Taxonomic review of the tree snail genus Amphidromus Albers, 1850 (Pulmonata: Camaenidae) in Laos, with the description of two new species, pp. 1-40 in European Journal of Taxonomy 330 on pages 10-14, DOI: 10.5852/ejt.2017.330, http://zenodo.org/record/3829744