Coptocheilus yangi, Chen, 2021

Chen, Zhe-Yu, 2021, A review of Coptocheilus Gould, 1862 from China, with description of a new species (Gastropoda: Caenogastropoda: Pupinidae), Journal of Natural History 54 (41 - 42), pp. 2703-2712 : 2705-2706

Coptocheilus yangi Z.-Y. Chen, n. sp. 杨氏裂唇螺

( Figure 1 )

Type material. Holotype HBUMM 10024 , paratype HBUMM 10025 , Yunnan Province, Hani- Yi Autonomous Prefecture of Honghe (红河哈尼族彝族自治州), the mountainous area in the southwest of Mengzi City (蒙自市, 23°23′N, 103°21′E), collected by local people. 2018. ex. coll. Hao Yang (Mr. Hao Yang); paratypes CZY/2 , QL/2 , Yunnan Province, Hani and Yi Autonomous Prefecture of Honghe , Mengzi City , Zhicun Town (芷村镇, 23°23’N, 103°21’E), 2021-ii, leg. Yi-Feng Liu.

Measurements. H: 21.75–24.62 mm, D: 9.43–11.04 mm (n = 4).

Diagnosis. A large Coptocheilus species with fusiform and reddish-purple shell, teleoconch with dense and weak ribs and a strong periumbilical keel present.

Description. Shell large, spindle-shaped, reddish-purple, about 7.5 whorls. Body whorl equal with or slightly contracted than the penultimate whorl. Protoconch consists of 1.75 matt whorls. Teleoconch with dense and weak ribs. Most ribs regular, some are incomplete, be covered or two or more ribs are fused. Some continuous neighbouring ribs of the body whorl have nodules, formed some inconspicuous spiral striae. Suture shallow. Aperture circular, offset to the outside, distinctly reverse oblique to the shell axis. Peristome pale brownish and continuous, two layers present. Outer peristome expanded and slightly reversed. Inner peristome thickened, smaller and brighter than the former. Umbilicus narrow and shallow. A strong but blunt periumbilical keel present, its colour is slightly lighter than of the rest of the shell. Operculum corneous, with segregated multilayers. The outer surface flat, consist of many thinner multilayers. The inner surface slightly convex outwards, the middle part generally depressed with an elevated, pointed, but blunt nipple. A weak concentric depression presents or absents near the margin.

Etymology. The name is in memory of my friend, Mr. Hao Yang, who made this species available for study.

Distribution. Yunnan.This species is known only from a limited area around the type locality.

Remarks. The strong periumbilical keel present in the new species is not found in the most potentially sympatric species (e.g. Coptocheilus inermis ). Only two species, namely Coptocheilus cochinchinensis ( Rochebrune, 1882) and Coptocheilus messageri ( Bavay & Dautzenberg, 1909) share this characteristic. Coptocheilus yangi Z.-Y. Chen, n. sp. can be distinguished from these two species by its dark shell, sloping aperture and dense, weak ribs.

Figures

Figure 1. A, Coptocheilus yangi n. sp., holotype HBUMM 10024. B, outer side of operculum. C, inner side of operculum. Scale bar ‘a’ = 10 mm and refers to A, scale bar ‘b’ = 5 mm and refers to B and C. Photos: Zhe-Yu Chen.