Achalinus sheni, Ma & Xu & Qi & Wang & Tang & Huang & Jiang, 2023

Ma, Shun, Xu, Yu-Hao, Qi, Shuo, Wang, Ying-Yong, Tang, Shan-Shan, Huang, Song & Jiang, Jian-Ping, 2023, Discovery of a new cryptic Achalinus Peters, 1869 (Serpentes, Xenodermidae) species from Hunan Province, China, ZooKeys 1181, pp. 9-27 : 9

publication ID

https://dx.doi.org/10.3897/zookeys.1181.109462

publication LSID

lsid:zoobank.org:pub:E13F88C6-7797-44FD-828A-3D9E4FF38475

persistent identifier

https://treatment.plazi.org/id/7FBF50AF-C1D8-46C6-8B66-A5805598AFF8

taxon LSID

lsid:zoobank.org:act:7FBF50AF-C1D8-46C6-8B66-A5805598AFF8

treatment provided by

ZooKeys by Pensoft

scientific name

Achalinus sheni
status

sp. nov.

Achalinus sheni sp. nov.

Figs 3 View Figure 3 , 4 View Figure 4 , 5 View Figure 5 , 6 View Figure 6

Chresonymy.

Achalinus spinalis : Li et al. (2010).

Type material.

Holotype. ANU20230014 (field number HSR23019, Fig. 3 View Figure 3 ), an adult male, collected on 21 March 2023 (27°55′11″N, 111°55′3″E; 408 m a. s. l.), Qixingjie Town, Lianyuan City, Hunan Province, China by the team of Song Huang.

Paratypes. Three males, ANU20230012 (field number HSR23011, Fig. 4A View Figure 4 ), ANU20230013 (field number HSR23012, Figs 4B View Figure 4 , 5 View Figure 5 ), ANU20230015 (subadult male, field number HSR23020, Fig. 4C View Figure 4 ), with the same collecting information as the holotype; CIB 119043, a juvenile male, collected on 20 October 2015 by Bing Zhou and Shanshan Tang from Shumuyuan, Nanyue District, Hunan Province, China (27°15′59″N, 112°43′15″E; 358 m a.s.l., Fig. 4D View Figure 4 ).

Etymology.

The species name " Achalinus sheni " is named for the memories of the Chinese herpetologist, Prof. You-Hui Shen (沈猷慧), who worked in Hunan Normal University and made great contributions to the herpetological research of China, particularly in Hunan Province where the new species is found. We suggest “Shen’s Odd-scale Snake" or “Shen’s Burrowing Snake" as its English name and “沈氏脊蛇” ( Shěn Shì Jǐ Shé) as its Chinese name.

Diagnosis.

(1) dorsal scales strongly keeled, 23 rows throughout the body, the outmost row smooth and significantly enlarged; (2) tail relatively short, TaL/TL 0.183 ~ 0.224; (3) the suture between internasals subequal to the suture between prefrontals; (4) loreal one, subrectangular, LorH/LorL 0.53 ~ 0.57; (5) ventrals 161-170, anal entire, subcaudals 55-61, not paired; (6) the length of supraocular equal to or longer than the length of upper anterior temporal; (7) vertebral line inconspicuous and subcaudal streak absent.

Description of holotype.

An adult male with a total length of 371.3 mm (SVL 292.2 mm and TaL 79.1 mm); tail relatively short, Tal/TL 0.213; body slender, cylindrical; head length (HL) 10.74 mm, head width 5.13 mm, HL/HW 2.09, slightly distinct from neck; eye small, ED 1.25 mm, with an oval pupil; maxillary teeth 21. Rostral small, triangular, only the upper tip visible from above. Length of the suture between the internasals (LSBI 1.38 mm) subequal to the length of the suture between the prefrontals (LSBP 1.36 mm). Nostril in the anterior part of the nasal. Loreal one, subrectangular, loreal height (LorH) 0.85 mm, loreal length (LorL) 1.49 mm, LorH/LorL 0.57. Frontal one, pentagonal, pointed backwards, much shorter than the parietals. Parietals paired. No preoculars and postoculars. Supraocular one, length of supraocular (SPOL 1.59 mm) longer than the length of upper anterior temporal (ATUL 1.42 mm, SPOL/ATUL 1.12). Temporals 2+2+3, the anterior two contact the eye, the lower anterior temporal much larger, the upper medium temporal much larger, the upper posterior temporal much larger and separated from the other side one by one scale. Supralabials 6, 4th-5th contact the eye, the last one much elongated. One mental. Two chin shields, the anterior pairs longer than the posterior pairs. Infralabials 5, the first one contact with each other after the mental and before the 1st chin shields, 1st-3rd touch the 1st chin shields.

Dorsal scales strongly keeled, 23 rows throughout the body, the outmost row smooth and significantly enlarged. Ventrals 161; anal entire; subcaudals 60, not paired.

Colouration of holotype in life.

Scales tinged weakly iridescent and metallic lustre. Dorsum dark brown and the five innermost dorsal scale rows a little darker, forming an inconspicuous longitudinal vertebral line. Chin shields are tan. Ventrals generally light brown, darker on both sides, free margins of ventral scales greyish-white. Ventral side of tail brownness.

Colouration of holotype in preservation.

The dorsal surface of the body uniformly brownish-black, slightly tinged with iridescence and the longitudinal vertebral line a little darker. Chin shields light brown. Ventrals generally creamy-brown, darker on both sides, free margins of ventral scales greyish-white. Ventral side of tail light brown.

Variation.

Measurements, body proportions and scale counts are listed in Table 3 View Table 3 . All paratypes are very similar to the holotype, except in the following: (1) paratype ANU20230004 has six infralabials on the left side; (2) relatively shorter supraoculars (SPOL/ATUL): ANU20230012: 1.03, ANU 20230013: 0.99, ANU20230004: 1.01; (3) more ventrals: ANU 20230013: 166, CIB 119043: 170; (4) less subcaudals: ANU 20230013: 57, ANU20230015: 58, CIB 119043: 55; (5) dorsum dark brown, venter greyish-white, both sides of ventral scales are taupe and ventral view of tail light grey in both subadult male ANU20230015 and juvenile male CIB 119043.

Distribution and habits.

Achalinus sheni sp. nov. is currently only known from Hunan Province, China: Lianyuan City and Nanyue District (350-410 m a.s.l.). The native vegetation in the type locality is subtropical evergreen broad-leaved forests. Areas near the locality where the specimen CIB 119043 was collected is largely covered with artificial coniferous forest dominated by Cryptomeria spp. This new species’ population status requires further investigation. The conservation status for the new species is recommended to rate as data deficient (DD).

Kingdom

Animalia

Phylum

Chordata

Class

Reptilia

Order

Squamata

Family

Xenodermidae

Genus

Achalinus