Description of a New Species of Kukri Snake (Serpentes: Colubridae: Oligodon) from Xizang, China

Abstract

A new species of the Kukri snake genus Oligodon is described from Medog County in the eastern Himalayas of China. The species, named Oligodon zhangfujii sp. nov., can be distinguished from all known congeners by a combination of the following morphological characteristics: (1) 17-1715 dorsal scale rows; (2) six supralabials, third and fourth entering orbit; (3) one loreal present; (4) seven infralabials, first to fourth in contact with anterior chin shields; (5) 173 ventral scales and 47 pairs of subcaudal scales; (6) cloacal plate divided; (7) hemipenis single, shallowly bilobed, with large calcareous spines and a calyx area, sulcus spermaticus single; and (8) eight maxillary teeth. Phylogenetic analyses based on two mitochondrial genes revealed that this species occupies an independent phylogenetic position, distinct from the eight recognized species groups within the genus, and represents a sister taxon to the clade comprising the O. theobaldi and O. cinereus groups. The description is based on a single road-killed individual. As such, ecological data for the species remain sparse, underscoring the need for additional field surveys across the eastern Himalayan region.

Headnote

Abstract A new species of the Kukri snake genus Oligodon is described from Medog County in the eastern Himalayas of China. The species, named Oligodon zhangfujii sp. nov., can be distinguished from all known congeners by a combination of the following morphological characteristics: (1) 17-1715 dorsal scale rows; (2) six supralabials, third and fourth entering orbit; (3) one loreal present; (4) seven infralabials, first to fourth in contact with anterior chin shields; (5) 173 ventral scales and 47 pairs of subcaudal scales; (6) cloacal plate divided; (7) hemipenis single, shallowly bilobed, with large calcareous spines and a calyx area, sulcus spermaticus single; and (8) eight maxillary teeth. Phylogenetic analyses based on two mitochondrial genes revealed that this species occupies an independent phylogenetic position, distinct from the eight recognized species groups within the genus, and represents a sister taxon to the clade comprising the O. theobaldi and O. cinereus groups. The description is based on a single road-killed individual. As such, ecological data for the species remain sparse, underscoring the need for additional field surveys across the eastern Himalayan region.

Keywords eastern Himalayas, hemipenis, Medog, Oligodon zhangfujii sp. nov., taxonomy

(ProQuest: ... denotes formula omitted.)

1. Introduction

The genus Oligodon Fitzinger, 1826, comprising 88 recognized species along with numerous cryptic taxa, is the second largest snake genus globally and the most diverse within Asia and the family Colubridae (Uetz et al., 2024; Lee et al., 2024). Members of Oligodon, commonly referred to as "Kukri snakes", are characterized by their broad, flattened, and curved dentition, Which resembles the Nepalese Kukri knife (Smith, 1943; David et al., 2012). This genus exhibits a wide geographic distribution across Asia, extending from Iran, South Asia, the Himalayas, southern China, the Indochinese Peninsula, and the Malay Archipelago (Lee et al., 2024). Despite their broad distribution and exceptional diversity, taxonomic research on Oligodon has been historically constrained due to inadequate specimen availability and limited sampling efforts (Duméril et al., 1854; Boulenger, 1890, 1894; Wall, 1923; Pope, 1935; Smith, 1943; Leviton, 1963; Wagner, 1976; Green et al, 2010; Lee et al, 2023).

Recent advances in molecular phylogenetics have begun to address these limitations. Lee et al. (2024) reconstructed the phylogeny of Oligodon based on the most comprehensive molecular dataset to date, representing approximately 62% of all known species within the genus. Their phylogenetic analysis resulted in an updated intrageneric classification comprising eight species groups: O. waandersi group, O. taeniolatus group, O. arnensis group, О. ornatus group, O. signatus group, O. theobaldi group, O. cinereus group, and O. cyclurus· taeniatus group. However, the phylogenetic placements of several congeners remain unresolved due to insufficient genetic data (Lee et al., 2024).

During a recent field survey conducted in Medog County, Xizang, China, a snake specimen was collected that exhibited distinct morphological traits not observed in any known Oligodon congener. Molecular analyses further supported these morphological observations, indicating that the specimen formed an independent lineage outside the established clades of the recognized species groups. This evidence strongly suggests that the Oligodon specimen from Medog, Xizang, represents a previously undescribed species, Which is formally proposed and described herein.

2. Materials and Methods

2.1. Specimens and morphological comparison A single snake specimen (CIB 121710) was discovered as a fresh road-killed carcass in Beibeng Township (29.2441· N, 95.1916° E; ca 1 115 т а.5.1), Medog County, Xizang, China. The specimen was fixed in 10% buffered formalin, subsequently preserved in 75% ethanol, and deposited in the Herpetological Museum of the Chengdu Institute of Biology (CIB), Chinese Academy of Sciences.

External measurements were recorded with digital calipers following the methods described by Ren et al. (2018), including total length (TL); snout-vent length (SVL); tail length (TaL); head length (HL); and head width (HW). Definitions and counting methods of pholidosis characters followed Dowling (1951a, b), Zhao (2006), including internasal, prefrontal, frontal, parietal, loreal (L), preocular, postocular, supraocular, supralabial (SpL), infralabial (IfL), temporal (TEM), chin shield, maxillary teeth (MT), dorsal scale row (DSR), ventral (VEN), and subcaudal (SC) counts. Dorsal scale rows were counted at three key points: one head length posterior to the head, midbody, and one head length anterior to the cloaca. Symmetrical features were recorded as left/right, except for maxillary teeth, which were counted on the left side only.

Hemipenial materials were prepared from the preserved specimen using eversion techniques adapted from previous studies (Pesantes, 1994; Myers and Cadle, 2003; Zaher and Prudente, 2003; Jiang, 2010). The everted hemipenes were reinflated with colored petroleum jelly and photographed using a digital camera mounted on a tripod. Multifocal images were combined and processed using Helicon Focus v7.0.2 Pro (Helicon Soft Ltd., Kharkiv, Ukraine). The descriptive terminology for hemipenial morphology followed previous studies (Cope, 1896; Dowling and Savage, 1960; Zhang et al., 1984). The following measurements were used for hemipenial description: hemipenial total length (HTL); hemipenial truncus length (HCL); hemipenial total width (HTW).

Morphological comparisons with all other recognized Oligodon congeners were conducted using original or subsequent supplemental species descriptions available in the literature (Table 1).

2.2. Phylogenetic sampling and analyses Liver tissue of the newly collected Oligodon individual was obtained from the fresh carcass specimen (CIB 121710) and then preserved in 95% ethanol and stored at -40°C. Genomic DNA was extracted using a DNA extraction kit (Sangon Biotech Co, Ltd., Shanghai, China). Partial sequences of two mitochondrial genes, 16S ribosomal RNA (16S) and cytochrome b (CYTB), were amplified using primers described by Green et al. (2010) and Burbrink et al. (2000). Polymerase chain reaction (PCR) amplifications were performed under the following cycling conditions: initial denaturation at 95 °C for 4 min, 35 cycles of denaturation at 95 °C for 40 s, annealing at 53 °C (for 16S)/ 48 °C (for CYTB) for 40 $, and extension at 72 °С for 60 $, followed by a final extension step at 72 °C for 10 min. The PCR products were purified using spin columns and sequenced bidirectionally with both forward and reverse primers by Sangon Biotech Co, Ltd. (Shanghai, China). All sequences were deposited in GenBank (16S: PQ675764; CYTB: PQ677973). Phylogenetic analyses incorporated alignments of selected segments by Lee et al. (2024) with the inclusion of the new sequences and two outgroup taxa Hebius vibakari (KP684155) and Oreocryptophis porphyraceus (GQ181130). To simplify the final phylogenetic tree, redundant individuals lacking genetic divergence within the dataset were removed.

DNA sequence alignment was performed using the Clustal W algorithm with default parameters (Thompson et al., 1997). The final alignment included 105 individuals, 103 of which belonged to the genus Oligodon. The aligned lengths were 557 base pairs (bp) for 16S and 1101 bp for CYTB. PartitionFinder2 identified the optimal partitioning scheme, and jModelTest v2.1.2 determined the best-fitting nucleotide substitution model. Phylogenetic relationships were inferred using maximum-likelihood (ML) with RaxmlGUI v1.3 (Silvestro and Michalak, 2012) and Bayesian inference (BI) with MrBayes v3.2.4 (Ronquist et al, 2012). For ML analysis, 1 000 bootstrap replicates were performed, with the resulting consensus tree representing the evolutionary history of the taxa analyzed. BI analysis was conducted with two independent runs of 10000000 generations, with sampling every 1 000 generations and the first 25% of samples discarded as burn-in, achieving a potential scale reduction factor (PSRF) of < 0.005.

3. Results

The ML and BI analyses resulted in identical topologies. Thus, the ML phylogeny is presented, with bootstrap support (BS) and Bayesian posterior probabilities (BPP) labeled at the nodes (Figure 1). Phylogenetic analysis delineated eight major clades of the genus Oligodon (...), corresponding to the species groups defined by Lee et al. (2024). The Oligodon specimen collected from Medog, Xizang, China (CIB 121710) formed an independent lineage, positioned outside all recognized species groups. This lineage was closely related to the O. theobaldi and O. cinereus groups (BS = 93, BPP = 1.00), serving as a sister taxon to the clade including these two groups (BS = 80, BPP = 1.00). Together, these groups were clustered with the O. ornatus, O. signatus, and O. cyclurus-taeniatus groups to form a superclade representing the Pan-Indochina region (BS = 60, BPP = 1.00). This superclade contrasted with the O. waandersi group from Wallacea and the O. taeniolatus and O. arnensis groups from Central Asia and South Asia.

Morphological examination of the specimen CIB 121710 revealed a unique combination of characteristics distinguishing it from all known congeners, as detailed in the comparison section below. Based on the combined morphological and phylogenetic evidence, the Oligodon specimen from Medog County, Xizang, China, is herein described as a new species.

4. Taxonomic account

Oligodon zhangfujii sp. nov.

Holotype CIB 121710 (field No. LJT-XZ 2023027) (Figures 2-3), adult male, collected by Dihao WU, Junjie HUANG, and Zongyuan GAO on 16 August 2023 from Beibeng Township (29.2441° N, 95.1916° E; ca 1 115 m asl), Medog County, Xizang, China.

Etymology The specific name zhangfujii refers to Prof. Fuji ZHANG (...) (1946), a herpetologist from the Chengdu Institute of Biology, Chinese Academy of Sciences, who has significantly contributed to studies on the hemipenial morphology of Chinese reptiles.

Common name Zhang's Kukri snake (in English); zhang shi xiao (... shé (5K FG/NSLHE in Chinese).

Diagnosis The new species is assigned to the genus Oligodon based on its enlarged, compressed, blade-like posterior maxillary teeth, large rostral scale, and characteristic head pattern (Wall, 1923; Smith, 1943). The new species is distinguished from all other congeners by a combination of the following morphological characters: (1) 17-17-15 dorsal scale rows; (2) six supralabials, third and fourth entering orbit; (3) one loreal present; (4) seven infralabials, first to fourth in contact with anterior chin shields; (5) 173 ventral scales and 47 pairs of subcaudal scales; (6) cloacal plate divided; (7) hemipenis single, shallowly bilobed, with large calcareous spines and a calyx area, sulcus spermaticus single; and (8) eight maxillary teeth.

Description of holotype CIB 121710, adult male, TL 603 mm, SVL 465 mm, Tal. 138 mm, TaL/TL 0.229, body cylindrical and robust but elongate, tail robust, tapering progressively.

Head short, HL 15.8 mm, HW 10.3 mm, HL/HW 1.53, slightly flattened, slightly distinct from neck; snout elongate, slightly rounded, extending well beyond lower jaw; rostral triangular, thick, curved onto upper snout surface, slightly visible from above; nasal trapezoidal, divided, with large oval nostril opening centrally; pupil round; internasals two, half oval in shape, in broad contact; prefrontals two, subrectangular, distinctly wider than long, suture between prefrontals about equal to that between internasals; frontal large, symmetrical hexagon, distinctly longer than wide; supraocular 1/1, sub-rectangular, length greater than width distinctly, anterior narrower; parietals large, sub-pentagonal, suture between parietals slightly shorter than length of frontal; loreal 1/1, very small, rectangular, not entering orbit; preoculars 1/1, sub-rectangular, height significantly longer than width; postoculars 2/2, sub-rectangular; upper postocular length almost equal to width, lower preocular longer than wide; anterior temporals 1/1, rectangular, almost twice as long as Wide; posterior temporals 2/2, sub-rectangular, upper part longer than lower part; supralabials 6/6, first triangular, in contact with nasal and loreal, second to fifth sub-rectangular, increasing in size, fifth largest, 1.5 times higher than fourth and 2.5 times wider, second in contact with nasals, loreal, and preorbital, third and fourth entering orbit, latter higher than former, third in contact with preocular, fourth in contact with lower postocular, fifth in contact with lower postocular and anterior temporals, sixth significantly smaller than fifth, in contact With lower posterior temporals. Chin shields pairs two, anterior pair elongate, half of length, posterior pair subrectangular; infralabials 7/7, first pair in broad contact, first to fourth in contact with anterior chin shields, fourth largest, touching posterior chin shields, some scales on dorsal part of head with warty granules.

Dorsal scale rows 17-17-15, all smooth; vertebral scales similar to other dorsal scales in shape and size. Dorsal scale row reductions:

...

Ventrals 173, angulate laterally; cloacal plate divided; subcaudals 47, all paired; terminal caudal scale forming tip, part of tail tip missing.

Maxillary teeth eight on both sides, formula 6+2, last two distinctly enlarged, separate from anterior maxillary teeth by small diastema.

Hemipenis fully everted (left side), relatively large, robust, Yshaped, hemipenial total length (HTL) 22.65 mm, hemipenial total width (HTW) 12.72 mm, HTL/HTW 178%; shallowly bilobed, bilaterally symmetrical, hemipenial truncus length (HCL) 20.70 mm, HCL/HTL 91%.

Everted hemipenis densely ornamented with large spines and calyxes, divided from basal to distal into basal naked area, pine area, and calyx area; naked area height shortest, one-sixth of HTL, barely ornamented, basal hook absent; spine area extended to approximately half of HTL, sparsely decorated with 29 calcareous spines; spines enlarged, distinct, slightly symmetrical on both sides, in almost 3-4 oblique lines, most basal two enlarged; calyx area largest, densely ornamented with smooth calyces, calyx rows nine, fleshy, moderately reticulated on each lobe to distal end. Crotch distinctly swollen on sulcus side, surface naked, protruding at medial center of hemipenis, slightly lower than distal end of lobes; lobes on both sides of crotch sunk on sulcus side; crotch on asulcate side sunk centrally, length one-fourth of HTL. Sulcus spermaticus single, centripetal, extended to center of crotch, closed at distal end, sulcus lips distinctly developed, largely overlapping from calyx area, sulcus mostly obscured (Figure 3).

Retracted hemipenis (right side) extending to SC 8, origin of т. retractor penis magnus at SC 23.

Coloration of holotype In fresh specimens (Figure 2), dorsal surface of head brownish; forward golden-edged black chevron and arrowhead-shaped patterns on top of head; the chevron extends backward from anterior margin of prefrontal, across entire ocular globe, to third, fourth, and fifth supralabials; the arrowhead-shape extends backward from approximately center part of frontal through parietal to posterior nape, widening from anterior parietal, across whole of posterior temporals, sixth supralabials, posterior nape, reaching half of ventral scales; spaces between arrowheadshape brown to white after parietals, expanding to ventral scales; black stains on snout; postoculars, temporals, parts of fifth supralabials, and parietals with golden and grey-black blots. Iris golden. Dorsal body and tail grayish black with 38 and eight black-edged white transverse bands respectively; white transverse bands one or half dorsal scale in width, some bands indistinct or broken; first transverse band at 1.2 head lengths posterior to the head; single stained white spot spanning five vertebral scales posterior to parietal, one scale wide, with stained surrounding scale edges. Ventral surface of head with two pairs of black spots, former on lower part of second infralabials, anterior part of anterior chin shields, latter on posterior part of fourth infralabials, lower part of fifth infralabials, upper part of following scale; abdomen with numerous black rectangular patches, covering entire ventral scales or half of ventral scales, patches becoming denser backward; some subcaudals patches like abdominal patches.

Distribution and habitat Currently, Oligodon zhangfujii sp. nov. is only known from its type locality in Beibeng Township, Medog County, Xizang, China. The only individual found thus far was collected as a fresh road-killed carcass on the main road from Beibeng Township to Gelin Village, following light rain at about 1:00 am on 16 August 2023. The surrounding habitat comprises evergreen broadleaf forest and gramineous scrubs (Figure 4). The survey in Beibeng Township and neighboring areas lasted five days in mid-August 2023, and only one individual of this species was observed. During the survey, Pareas monticola (Cantor, 1839), Bungarus bungaroides (Cantor, 1839), Ptyas nigromarginata (Blyth, 1854), Lycodon septentrionalis (Günther, 1875), Calotes medogensis Zhao & Li, 1984, and Sphenomorphus indicus (Gray, 1853) were observed as co-occurring reptile species. Due to the limited observations, ecological information about this species remains unknown, necessitating comprehensive field surveys in the near future to better understand its habitat and distribution.

Comparison Oligodon zhangfujii sp. nov. has a very unusual coloration pattern, Which can be distinctly distinguished from all known species of the genus.

Other thirteen species of Oligodon are currently known from the eastern Himalayas (Chettri and Bhupathy, 2007; Ahmed et al, 2009; David et al, 2011; Che et al, 2020; Malsawmdawngliana et al., 2022): O. albocinctus, O. catenatus, O. cinereus, O. cyclurus, O. dorsalis, O. erythrogaster, O. erythrorhachis, O. juglandifer, O. kheriensis, O. lipipengi, O. melaneus, O. melanozonatus, and O. theobaldi.

Among these congeners in the eastern Himalayas, Oligodon zhangfujii sp. nov. can be distinguished based on its 17-17-15 DSR count (vs. 13 throughout in O. catenatus, 15-15-13 in O. erythrorhachis and O. dorsalis, 19-19-15 in O. albocinctus, O. cyclurus, O. juglandifer, and O. lipipengi, and 19-19-17 in O. kheriensis. Moreover, the new species can be distinguished from O. catenatus by loreal and internasals present (vs. absent), from O. erythrorhachis by loreal present (vs. absent), from O. albocinctus, O. cyclurus, O. juglandifer, and O. lipipengi by hemipenis with large spines (vs. without spine), and from O. kheriensis and O. dorsalis by six SpL (vs. eight and seven, respectively).

Oligodon zhangfujii sp. nov. can be distinguished from those congeners in eastern Himalayas with a 17-17-15 DSR count based on six SpL (vs. eight in O. cinereus and O. theobaldi and seven in O. erythrogaster and O. melaneus). Moreover, the new species differs from O. cinereus and O. erythrogaster by hemipenis with large spines (vs. without), from O. melaneus by 173 VEN and 47 SC (vs. 144-152 VEN and 42 SC in males), and from O. theobaldi by 47 SC and eight MT (vs. 3042 SC and 15-16 MT).

Oligodon zhangfujii sp. nov. can be distinguished from O. melanozonatus by loreal present (vs. absent), seven IL (vs. six), and dorsal pattern grayish black with 38 and eight blackedged white transverse bands across body and tail (vs. dorsal pattern light brown with 20 and four poorly defined black transverse bands across body and tail).

For the remaining 75 Oligodon congeners, Oligodon zhangfujii sp. nov. can be distinguished based on its 17 midbody DSR (vs. 13 in O. annamensis, О. eberhardti, O. mcdougalli, and O. planiceps; 15 in O. annulifer, O. bivirgatus, O. brevicauda, O. calamarius, O. everetti, O. hamptoni, O. inornatus, O. jintakune, O. kampucheaensis, O. lacroixi, O. lungshenensis, O. modestus, O. nikhili, O. notospilus, O. ornatus, O. petronellae, O. praefrontalis, O. propinguus, O. rostralis, O. teyniei, O. tolaki, O. torquatus, O. transcaspicus, O. unicolor, O. vertebralis, O. waandersi, and О. woodmasoni; 19 in O. formosanus, O. ocellatus, O. taeniatus, and O. tuani; 19 or 21 in O. purpurascens; and 21 in O. fasciolatus and O. splendidus). Furthermore, Oligodon zhangfujii sp. nov. can be differentiated based on 17-17-15 DSR (vs. 17 throughout in O. meyerinkii, O. octolineatus, O. perkinsi, and O. woodmasoni).

Oligodon zhangfujii sp. nov. is further distinguishable by its spinose hemipenis (vs. hemipenis without spine in O. ancorus, O. huahin, О. joynsoni, О. maculatus, O. nagao, О. phangan, O. promsombuti, О. saiyok, O. speleoserpens, O. barroni, O. cruentatus, O, chinensis, О. culaochamensis, O, deuvei, O. macrurus, O. moricei, O. mouhoti, O. pseudotaeniatus, and O, saintgironsi) and divided cloacal plate (vs. entire cloacal plate in O. booliati, O. bitorquatus, O. forbesi, O. signatus, and O. trilineatus).

Oligodon zhangfujii sp. nov. can be further differentiated based on its six SpL (vs. seven in O. sublineatus, O. taeniolatus, O. affinis, O. arnensis, O. travancoricus, O. venustus O. tillacki, and O. russelius) and 173 VEN and 38 black-edged white transverse bands across dorsal body (vs. 152-157 VEN in males and 2838 light, dark-bordered oval spots on dorsal body in O. pulcherrimus).

5. Discussion

Lee et al. (2024) proposed a division of the genus Oligodon into eight species groups, corresponding to clades А-Н. Our phylogenetic analysis recovered seven of these clades, with some differences in the relationships among clades A-C (Figure 1). Notably, clade F (O. theobaldi group) was found to be paraphyletic with respect to clade G (O. cinereus group). However, the combined node for clades F and G was strongly supported (BS 80, BPP 1.00), suggesting a close evolutionary relationship between these groups. This finding is consistent with Lee et al. (2024), in which the O. theobaldi and O. cinereus groups were identified as sister taxa forming a stable clade (BS 100, BPP 1.00). Furthermore, our analysis revealed consistent relationships among the five species groups from the PanIndochina region. The phylogenetic structure was resolved as (О. cyclurus-taeniatus group + (O. ornatus group + O. signatus group) + (О. cinereus group + О. theobaldi group)), with moderate to strong support (BS = 60, BPP = 1.00). This topology closely matches the findings of Lee ег al. (2024), which reported higher support values (BS = 98, BPP = 1.00). These differences in topology and lower support values in our analysis may result from the smaller sample size and fewer genetic markers used in this study. Nonetheless, our results are broadly consistent with previous findings, supporting the reliability of our phylogenetic framework.

Beyond these eight established species groups, the newly described species, Oligodon zhangfujii sp. nov., formed an independent lineage outside all recognized clades and was sister to the (O. cinereus group + O. theobaldi group) clade (BS = 93, BPP = 1.00). Morphologically, the hemipenis of the new species is subcylindrical, shallowly bilobed, with large spines and a calyx area, and a single sulcus spermaticus, and it can be readily distinguished from other Oligodon species based on our available hemipenial data of the genus. These distinct differences suggest that Oligodon zhangfujii sp. nov. may constitute an unnamed species group within the genus Oligodon. Nonetheless, as only a single specimen is available for this species, we consider further research with more specimens and additional genetic data will be necessary to confirm and refine this hypothesis.

The discovery of Oligodon zhangfujii sp. nov. takes the fifteenth species of this genus in the eastern Himalayas, where is a well-known hotspot region. Below we present an identified key to these 14 Oligodon species, to aid future research.

1A. Thirteen dorsal scale rows throughout dorsal body ......................... O. catenatus

1B. More than 13 dorsal scale rows at midbody ............. 2

2A. Fifteen dorsal scale rows at midbody ..............3

2B. More than 15 dorsal scale rows at midbody.................4

3A. Loreal absent ..................O. erythrorhachis

3B. Loreal present ................... O. dorsalis

AA. Nineteen dorsal scale rows at midbody ..............5

AB. Seventeen dorsal scale rows at midbody .............. 9

5A. Dorsum uniform; arrowhead-like cephalic and nape marking absent ....................O. kheriensis

5B. Dorsum not uniform; arrowhead-like cephalic and nape marking present ......................6

6A. Hemipenis deeply bifurcated .................7

6B. Hemipenis not as such ....................8

7A. 37-48 subcaudals; dorsum with butterfly-shaped blotches ....................O. juglandifer

7B. 53-68 subcaudals; dorsum reticulated, or has oval blotches ................. ?. cyclurus

8A. Dorsum with transverse bands ............... ?. albocinctus

8B. Dorsum with oval blotches .......... O. lipipengi

9A. Six supralabials ............. 10

9B. More than six supralabials ............11

10A. Loreal absent; six infralabials .......... O. melanozonatus

10B. Loreal present, seven infralabials............... O. zhangfujii sp. nov.

11A. Seven supralabials ..........12

11B. Eight supralabials ..........13

12A. Loreal absent ......... O. erythrogaster

12B. Loreal present ......... O. melaneus

13A. Cloacal plate completed; hemipenis without spines ............. O. cinereus

13B. Cloacal plate divided; hemipenis with spines ............ O. theobaldi

Nomenclatural acts registration The electronic version of this article in portable document format represents a published work according to the International Commission on Zoological Nomendature (ICZN), and hence the new names contained in the electronic version are effectively published under that Code from the electronic edition alone (see Articles 8.5-8.6 of the Code). This published work and the nomenclatural acts it contains have been registered in ZooBank, the online registration system for the ICZN. The ZooBank LSIDs (Life Science Identifiers) can be resolved and the associated information can be viewed through any standard web browser by appending the LSID to the prefix http://zoobank.org/.

Publication LSID: urn:lsid:zoobank.org:pub:9FBD8718-586EAAAA-B536-890770F3FB90

Oligodon zhangfujii LSID: urn:1sid:zoobank.org:act:43653 CBB-CA31-4F18-9D35-FD920C851B24

Acknowledgements We thank Ruihan LI and Ruxue LI for their help in the field and laboratory works. We thank Gernot VOGEL and two anonymous reviewers for their constructive suggestions on the manuscript. This work was supported by grants from National Key R&D Program of China (Grant No. 2022YFC2602500), the Second Tibetan Plateau Scientific Expedition and Research Program (STEP) (2019QZKKO501), National Natural Science Foundation of China (32200363, 32325011, 32220103004, 32300370, 32400361), International Partnership Program of Chinese Academy of Sciences (071GJHZ2023041MI), China Postdoctoral Science Foundation (2023M743416), Sichuan Science and Technology Program (2023NSFSC1155, 2024NSFSC1180), Taxonomist Position, Chinese Academy of Sciences (CAS-TAX-24-051, CAS-TAX-24-052), and Biological Resources Programme, Chinese Academy of Sciences (KFJ-BRP-017-086, KFJ-BRP-017-065).

Sidebar

* authors: Prof. Jiatang LI, from Chengdu Institute of Biology (CIB), Chinese Academy of Sciences (CAS), Chengdu, Sichuan, China, with his research focusing on taxonomy, phylogenetics, biogeography, genomics, and evolution of amphibians and reptiles; Dr. Zhitong LYU, from CIB, CAS, Chengdu, Sichuan, China, with his research focusing on the taxonomy, phylogenetics, and conservation of Chinese Herpetology.

E-mail: [email protected] (Jiatang LI); [email protected] (Zhitong LYU)

Received: 13 November 2024 Accepted: 9 December 2024

Published Online: 13 December 2024

2095-0357/0 2025 Asian Herpetological Research Editorial Office and Science Press. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Scientific Editor: Bin WANG

How to cite this article:

Jiang K., Wu D. H., Huang J. J, Ren J. L., Gao Z. Y., Lyu Z. T., Li J. T. 2025. Description of a new species of Kukri snake (Serpentes: Colubridae: Oligodon) from Xizang, China. Asian Herpetol Res, 16(1): 36-48. DOI: 10.3724/ahr.20950357.2024.0058. CSTR: 32242.14.ahr.2095-0357.2024.0058

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