Pareas menglaensis, Wang & Che & Liu & Li & Jin & Jiang & Shi & Guo, 2020

Wang, Ping, Che, Jing, Liu, Qin, Li, Ke, Jin, Jie Qiong, Jiang, Ke, Shi, Lei & Guo, Peng, 2020, A revised taxonomy of Asian snail-eating snakes Pareas (Squamata, Pareidae): evidence from morphological comparison and molecular phylogeny, ZooKeys 939, pp. 45-64 : 45

Pareas menglaensis sp. nov. Figure 4

Holotype.

YBU 14124, adult female, collected from Mengla County, Yunnan Province, China, at an elevation of 700 m above sea level in June 2014.

Paratypes.

YBU 14141 and YBU 14142, two adult males from the same locality as the holotype but collected in July 2012.

Diagnosis.

(1) prefrontal separating from orbit; (2) three chin-shield pairs, anterior pair smaller than other two; (3) 9-13 rows of mid dorsal scales keeled; (4) three rows of mid dorsal scales enlarged; (5) single loreal, not bordering orbit; (6) two preoculars, 2-3 suboculars, single postocular; (7) 9-11 temporals (3+3+3, 3+4+4, or 3+4+3); (8) seven supralabials, not bordering orbit; (9) 7-8 infralabials; (10) 3-5 maxillary teeth; (11) cloaca undivided; (12) dorsal scales in 15 rows throughout; (13) 176-177 ventral scales; (14) 65-79 subcaudals, paired.

Description of holotype.

Male, SVL 472 mm, TL 111 mm, TL/total length 0.24; body elongated; snout distinctly blunt; head distinct from neck. Rostral invisible from above, much deeper than broad; nasals undivided. Internasals subtriangular, wider than long; prefrontals pentagonal, length equal to width, not touching eyes; frontal hexagonal, longer than wide; parietals irregular, longer than wide; one supraocular, longer than diameter of orbit; single loreal, separating from eyes; two preoculars; one postocular; two suboculars; nine or ten temporals, 3+4+3 on left and 3+3+3 on right; seven supralabials, not bordering orbit; seven or eight infralabials, first four in contact with anterior chin-shields; three chin-shield pairs, posterior pair larger than other two; ventral scales 177; cloaca undivided; subcaudals 65, paired; dorsal scales in 15 rows throughout, three median rows enlarged, all keeled except for outer two; five maxillary teeth on both sides.

Dorsal surface nearly uniformly light brown with slightly visible black cross-bands. Head light brown with black dusted spots. Thin postorbital stripe extending from postocular to neck. Belly yellowish white, anterior portion without spots except for lateral edges mottled with almost striped dark brown spots, striped spots gradually becoming invisible backwards. Spots and specks on posterior portion of belly appear and become denser later.

Description of paratypes.

The paratypes agree in most respects with the description of the holotype. A comparison of the most important morphological characters is summarized in Suppl. material 3: Appendix S3.

Etymology.

The specific species is named after the type locality, Mengla County, Yunnan, China. We suggest the common name "Mengla Snail-eating Snake" in English and "Mengla Dun-tou-she" (勐腊钝头蛇) in Chinese.

Distribution.

This species is currently known only from the type locality Mengla County, Yunnan, China, with low mountain evergreen broad-leaved forest and a tropical monsoon climate type. It is expected to be found in the surrounding low mountainous areas and in neighboring Laos and Myanmar.

Comparison.

Pareas menglaensis sp. nov. can be distinguished from P. carinatus by 11 rows of dorsal scales strongly keeled at mid-body (vs. 3-5 rows feebly keeled), from P. nuchalis by prefrontal separated from orbit (vs. prefrontal bordering orbit), and from all other species of Pareas by two or three distinct narrow suboculars (vs. one thin elongated subocular).

Figures

Figure 4. Holotype of Pareas menglaensis sp. nov. (YBU 14124). General view (A); dorsal (B), ventral (C), lateral (D) and frontal (E) views of the head; dorsal (F) and ventral (G) views of the median body.