Clostophis charybdis, Páll-Gergely & Hunyadi, 2022

Páll-Gergely, Barna & Hunyadi, András, 2022, New and little-known species of Clostophis Benson, 1860 from Southeast Asia (Gastropoda: Eupulmonata: Hypselostomatidae), Raffles Bulletin of Zoology 70, pp. 417-439 : 430-434

Clostophis charybdis , new species

( Figs. 13 , 14 )

Type material. Holotype (SH: 1.18 mm, SW: 1.12 mm) ( HNHM 105327 ), Vietnam, Lạng SƠn Province , Bình Gia , eastern edge of the village, Di Chí Kéo Lèng (Thẩm Khuyên Cave), rock wall; 21°56.30′N, 106°23.82′E, 375 m a.s.l. (locality code: 2020/48), coll. A. Hunyadi, 17 February 2020 . Paratype: 1 shell, coll. HA, same data as for holotype ; 30 paratypes, coll. HA, Vietnam, Lạng SƠn Province, B ắc SƠn District , Long Dong, 3.8 km north from junction of roads no. QL1B (main road) and 241, 390 m a.s.l., 21°56.728′N, 106°19.447′E (locality code: 2020/51), coll. A. Hunyadi, 18 February 2020 .

Diagnosis. A concave conical Clostophis species with a wide umbilicus, a well-developed, elevated parietal, and a shorter, pointed palatal tooth situated slightly upper (more apically) than where the parietal tooth points.

Description. Shell concave conical, widest at its base, slightly higher than wide to slightly wider than high, body whorl conspicuously wider than penultimate whorl. Whorls very slightly, bluntly shouldered. Protoconch consisting of 1.25–1.5 whorls, finely pitted/granular, and spirally striated preceding the first teleoconch whorl. Entire shell consisting of 4.5–4.75 whorls, with relatively strong, irregular radial growth lines and equally strong, dense, equidistant spiral striae. Body whorl with few, ca. 16–18 spiral striae from apertural view. Umbilicus regularly growing, wide, shell width is ca. 2.5 times wider than umbilicus. Aperture oblique to shell axis, oval to rectangular with blunt sinulus area. Sinulus large, only slightly smaller than other side of aperture, and well separated due to elevated parietal tooth and palatal tooth. Parietal callus rather blunt, not smeared onto penultimate whorl. Peristome expanded, not reflected. Parietal tooth elevated straight, nearly reaching parietal callus. Parietal wall with a low but pointed tooth that is positioned slightly upper (more apically) compared to where the parietal tooth points.

Measurements (in mm). SH = 1.02–1.21, SW = 1.03–1.19 (n = 6).

Differential diagnosis. Among the Clostophis species possessing two parietal teeth, Clostophis incurvus PállGergely & Vermeulen, 2020 has a conical shell with a narrower umbilicus, and Clostophis platytrochus Páll-Gergely & Hunyadi, 2020 also has a more conical shell and a more pronounced oblique aperture with a more basally-situated palatal tooth.

Etymology. Named after Charybdis, the large whirlpool (or sea monster) of the Greek mythology, referring to the whirlpool-like umbilicus.

Figures

Fig. 13. Clostophis charybdis, new species (holotype, HNHM 105327).

Fig. 14. Clostophis charybdis, new species (paratype, coll. HA).