Endothyrella inexpectata Pall-Gergely

Pall-Gergely, Barna, Budha, Prem B., Naggs, Fred, Backeljau, Thierry & Asami, Takahiro, 2015, Review of the genus Endothyrella Zilch, 1960 with description of five new species (Gastropoda, Pulmonata, Plectopylidae), ZooKeys 529, pp. 1-70 : 11-12

Taxon classification Animalia Pulmonata Plectopylidae

Endothyrella inexpectata Pall-Gergely sp. n. Figures 4B, 6F, 8D, 9 A–B

Type material.

China, Sichuan Sheng (四川省), Panzhihua Shi (攀枝花市), Yanbian Xian (盐边县), Qinghe Xiang (箐河乡), Qinghepubu (箐河瀑布), Xianrendong (仙人洞), 1410 m, 27°03.834'N, 101°23.611'E, leg. Hosoda, T., Ohara, K., Okubo, K., Otani, J. U., 12.09.2013, NHMUK 20140023 (holotype, Figures 4B, 6F, 8D, 9 A–B), JUO/1 (paratype), TH/1 (paratype = juvenile shell); China, Sichuan Sheng (四川省), Liangshan Yizu Zizhizhou (凉山彝族自治州), Yanyuan Xian (盐源县), Bainiao Zhen (白鳥鎮), Kedengrongdong (柯登溶洞) (cave), 2620 m, 27°43.103'N, 101°31.021'E, leg. Hosoda, T., Ohara, K., Okubo, K., Otani, J. U., 13.09.2013, JUO/1 juvenile shell (not paratype); Sichuan Sheng (四川省), Liangshan Zhou (凉山州), Yanyuan Xian (盐源县), Baiwu Zhen (白乌镇), eastern edge of Kedeng Cun (柯登村), 2640 m, 27°43.897'N, 101°31.208'E, leg. Hunyadi, A., Szekeres, M., 11.06.2015., HA/1 paratype.

Diagnosis.

Shell very small, dextral, almost flat, relatively widely umbilicated with elevated callus; hairs standing in three lines on the body whorl; parietal wall with a single, curved lamella; palatal wall with six short plicae.

Description.

Shell dextral, with almost flat, very slightly domed dorsal side (protoconch slightly elevates from the dorsal surface); brownish or slightly reddish in colour; protoconch consists of 1.5-1.75 whorls, first whorls rather smooth, last 0.25-0.5 whorl regularly ribbed (Figure 6F); teleoconch with irregular, rough growth lines and spiral structure; sculpture stronger on the dorsal surface but still well-visible on the ventral surface; deciduous, slim and flat folds standing in three lines on the body whorl (Figure 8D); whorls 4.75, very much bulging, separated by deep suture; umbilicus moderately wide and deep; apertural lip whitish, thickened and slightly reflexed; callus strong, elevated, sharp and slightly S-shaped; with canals at both ends; no fold in the aperture.

One specimen (the holotype) was opened. The armature is situated very close to the aperture, palatal plicae visible from oblique view through the aperture. Parietal wall with a single curved lamella without additional denticles; arms of the lamella pointing posteriorly; palatal wall with six very short plicae becoming narrower posteriorly; the last one with an additional denticle posteriorly (Figures 9 A–B).

Measurements

(in mm): D: 6.6-6.7, H: 3.0-3.1 (n = 2, from different localities).

Differential diagnosis.

Endothyrella babbagei is much larger than Endothyrella inexpectata sp. n., and it has flatter whorls and has a weaker callus than the new species. Sinicola species of the same size have a keeled or shouldered body whorl and have two parallel parietal plicae anterior to or above the lamella (one near the upper, the other near the lower suture). Sicradiscus invius also occurs in Sichuan, but it is smooth (glossy) and has a strong apertural fold. See also under Endothyrella oglei and Endothyrella serica and Table 5.

Etymology.

The name inexpectata (meaning unexpected in Latin) refers to the surprizing new, especially dextral Endothyrella species in China.

Type locality.

Sichuan Sheng (四川省), Panzhihuashi (攀枝花市), Yanbian Xian (盐边县), Qinghe Xiang (箐河乡), Qinghepubu (箐河瀑布), Xianrendong (仙人洞), 1410 m, 27°03.834'N, 101°23.611'E.

Distribution.

Endothyrella inexpectata sp. n. is known from two localities in western Sichuan province, China (Figure 7).