Trichocathaica amphidroma ( Moellendorff , 1899)

Pall-Gergely, Barna, unyadi, Andras & Asami, Takahiro, 2018, Enantiomorphs and taxonomy of three conchological species in flat-shelled snails Trichocathaica (Pulmonata, Camaenidae), ZooKeys 810, pp. 19-44 : 23

Trichocathaica amphidroma ( Moellendorff, 1899) Figure 2

Euhadra amphidroma Möllendorff, 1899: 83, plate 4, figs 2, 2a, 3.

Trichocathaica amphidroma - Yen 1939: 150, plate 15, fig. 44.

Trichocathaica amphidroma - Yen 1939: 292, figs 1-4.

Material examined.

W-Sytschuan, Liu-Ting am Tung, coll. Möllendorff ex coll. Potanin, SMF 8942/1 lectotype (sinistral shell, D = 20.8 mm, H = 11.6 mm, Fig. 2 A–C); same data, SMF 8938/1 paralectotype (sinistral shell); W-Sytschuan, Thal des Tung, coll. Möllendorff ex coll. Potanin, SMF 8937a/3 sinistral, juvenile paralectotype shells; China (Szytschuan): W-Ufer d. Lu Ho (Ta Tu Ho) zw. Tapien und Ja sz’kou, ex Krejci-Graf, 05.08.1930, SMF 24667/8 sinistral + 9 dextral shells (1 of the dextral shells is photographed: Fig. 2 D–F); 2015/67 Sichuan, Ganzi Zhou, Luding Xian, Luding, rocks above bus station, approximate GPS coordinates: 29°54.451'N, 102°13.923'E, leg. Hunyadi, A., 15.06.2015, HA/6 sinistral shells.

Diagnosis.

Shell sinistral or dextral, body whorl rounded, teleoconch roughly wrinkled with large, triangular periostracal folds, fold scars represented as long curved lines.

Description.

Shell sinistral or dextral, spire slightly elevated, body whorl rounded, protoconch consists of 1.25-1.5 whorls, finely, irregularly wrinkled; entire shell with 5.5-5.75 whorls; teleoconch roughly, irregularly wrinkled, with large, triangular periostracal folds having long, curved (C-shaped) base; in specimens/shell parts without periostracum the base of folds visible as prominent curved lines on the surface; aperture subcircular, peristome slightly expanded, thin, sharp; inner thickening parallel to peristome weak.

Measurements (in mm).

D = 20.5-25.9, H = 10.3-13.1 (n = 6).

Differential diagnosis.

The fine sculpture of the teleoconch surface, namely the rough wrinkles and large triangular periostracal folds with the long base, distinguish this species form the other congeners.

Distribution.

This species is known from the valley of the Dadu River near Luding. We were not able to locate Tapien on a map. Wu (2001) also reported this species from Luding County (29.9°N, 102.2°E).