Amphidromus (Amphidromus) pervariabilis Bavay & Dautzenberg, 1909

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, European Journal of Taxonomy 330, pp. 1-40 : 10-14

publication ID	https://doi.org/ 10.5852/ejt.2017.330
DOI	https://doi.org/10.5281/zenodo.3848191
persistent identifier	https://treatment.plazi.org/id/03DAD35F-692F-EF05-FEEE-A9E5FE292223
treatment provided by	Carolina
scientific name	Amphidromus (Amphidromus) pervariabilis Bavay & Dautzenberg, 1909
status

Treatment

Amphidromus (Amphidromus) pervariabilis Bavay & Dautzenberg, 1909 View in CoL Figs 1 View Fig , 5 View Fig A−L; Table 1 View Table 1

Amphidromus pervariabilis Bavay & Dautzenberg, 1909b: 246-247 View in CoL . Type locality: Ban-Lao, Muong- Kong, Pha-Long, Pac Kha.

Amphidronus pervariabilis View in CoL – 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 View Fig 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 View Fig ), syntypes of A. pervariabilis var. “ bifasciata ”, from Ban-Lao, Muong- Kong, Pha-Long, Pac Kha (MNHM-IM- 2000-2059).

VIETNAM: 1 shell ( Fig. 5D View Fig ), syntype of A. pervariabilis var. “ goniostoma ”, from Phong-Tho, 22°34′ N, 103°22′ E (MNHM-IM- 2000-2058).

VIETNAM: 2 shells ( Fig. 5E View Fig ), syntypes of A. pervariabilis var. “ lilacina ”, from Ban-Lao (MNHM- IM- 2000-2052).

VIETNAM: 1 shell ( Fig. 5F View Fig ), syntype of A. pervariabilis var. “ minor ”, from unknown locality (MNHM- IM-2000-2050).

VIETNAM: 2 shells ( Fig. 5G View Fig ), syntypes of A. pervariabilis var. “ monozonalis ”, from Ban-Lao (MNHM- IM- 2000-2057).

VIETNAM: 1 shell ( Fig. 5H View Fig ), syntype of A. pervariabilis var. “ obesa ”, from Muong-Bo, 22°24′ N, 102°49′ E (MNHM-IM- 2000-2053).

VIETNAM: 1 shell ( Fig. 5I View Fig ), syntype of A. pervariabilis var. “ protracta ”, from Ban-Lao, Muong-Kong, Pha-Long, Pac Kha (MNHM-IM- 2000-2051).

VIETNAM: 2 shells ( Fig. 5J View Fig ), syntypes of A. pervariabilis var. “ tricolor ”, from Ban-Lao (MNHM- IM- 2000-2054).

Other material

LAOS: 3 shells ( Fig. 5 View Fig 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.