Biodiversity Data Journal :
Taxonomy & Inventories
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Corresponding author: Dian-Cheng Yang (snakeboy@sinoophis.com), Song Huang (snakeman@sinoophis.com)
Academic editor: Chelmala Srinivasulu
Received: 21 Mar 2024 | Accepted: 01 Jul 2024 | Published: 04 Jul 2024
© 2024 Shiyang Weng, Dian-Cheng Yang, Cong Wei, Peng Li, Zhangbo Cui, ZhiHao Jiang, Song Huang
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Weng S, Yang D-C, Wei C, Li P, Cui Z, Jiang Z, Huang S (2024) A new record and a novel morph description of Boiga stoliczkae (Squamata, Colubridae) from China. Biodiversity Data Journal 12: e123669. https://doi.org/10.3897/BDJ.12.e123669
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The Asian Cat Snake genus Boiga Fitzinger, 1826 includes 37 species, with high species diversity. Five species of Boiga have been recorded in China including B. multomaculata (Boie, 1827), B. kraepelini (Stejneger, 1902), B. cyanea (Duméril, Bibron & Duméril, 1854), B. guangxiensis (Wen, 1998) and B. siamensis (Nutaphand, 1971). Previously, the validity of the species Boiga stoliczkae (Wall, 1909) was controversial. B. stoliczkae was considered in synonymy with B. ochracea. Currently, the taxonomy of B. multomaculata and B. ochracea (Theobald, 1868) was revised so that B. multomaculata and B. ochracea actually represent a single species and B. stoliczkae was recognised as a valid species. B. stoliczkae was previously known to be found in the west from central Nepal through Darjeeling, Sikkim and Bhutan to Arunachal Pradesh and Assam in north-eastern India.
One adult female specimen of the Asian Cat Snake was collected from Gyirong County, near the China-Nepal border, Tibet, China during fieldwork on August 2023. We compared morphology and mitochondrial DNA sequence data with all the species of the genus Boiga. Both datasets strongly supported referring the Chinese specimens to B. stoliczkae (Wall, 1909) due to the 21 mid-dorsal scale rows and the uncorrected p-distance (mitochondrial DNA gene cytochrome b) between this specimen and B. stoliczkae which is 1.7%. We further described morphological characters of the Chinese specimen in detail and compared these with the specimens that had been previously described. The dorsal ground colour of the Chinese specimen is dark brown, with a black stripe distributed almost evenly across the tail. This is a novel morph of the species B. stoliczkae. The newly-collected Chinese specimen expands the distribution of the species on the Himalaya range.
Stoliczka´s Asian Cat Snake, Himalaya, distribution, colour and pattern polymorphism
The colubrid snake genus Boiga Fitzinger, 1826 includes 37 species, primarily arboreal snake species and these are distributed from the Southwest and Central Asia, South and Southeast Asia, many islands in the western Pacific to northern Australia, with particularly high species diversity in Southeast Asia (
Previously, the validity of the species B. stoliczkae (Wall, 1909) was controversial (
Five species of Boiga have been recorded in China including B. multomaculata (Boie, 1827), B. kraepelini (Stejneger, 1902), B. cyanea (Duméril, Bibron & Duméril, 1854), B. guangxiensis (Wen, 1998) and B. siamensis (Nutaphand, 1971) (
Sampling. The specimen was collected in the field using visual surveys. Liver and muscle tissues were extracted and immediately preserved in 95% ethanol. The specimen was fixed in 10% formaldehyde for one day, then transferred to 75% ethanol for permanent preservation and deposited in the Tibet Plateau Institute of Biology (collection number: HSR23050, voucher number TBR2023045). The animal study protocol was approved by the Laboratory Animal Care and Animal Ethics Committee of Tibet Plateau Institute of Biology. Furthermore, with the explicit permission and approval of the Tibet Autonomous Region Forestry and Grassland Administration, all sampling activities were conducted. We not only obtained the necessary permits, but also adhered to strict ethical guidelines, ensuring full compliance with local regulations and minimising any potential impact on the natural habitat.
Morphological examination. The number of ventral scales was counted according to
Abbreviations for measurements and scale characters are following
Molecular phylogeny. Genomic DNA was extracted from liver tissue using a Qiagen DNEasy blood and tissue extraction kit (Qiagen Inc., Valencia, CA). The partial mitochondrial DNA gene encoding cytochrome b (cyt b) was obtained by polymerase chain reaction (PCR) using primer pairs L14910 (5’-GAC CTG TGA TMT GAA AAC CAY CGT TGT-3’) and H16064 (5’-CTT TGG TTT ACA AGA ACA ATG CTT TA-3’) (
All sequences were aligned and compared with each other separately on the same gene loci by MEGA X software (
All the cyt b sequences in this study were retrieved from GenBank and uncorrected p-distances data are shown in Suppl. material
An adult female (Figs
Rostral subtriangular in frontal view, visible from above. Internasals paired, nearly trapezoidal, narrowing anteriorly. Prefrontals paired, more or less quadrangular, wider than long, in contact with loreal. Frontal shield-shaped, nearly straight anteriorly, pointed backwards, slightly longer than wide, supraocular 1/1, much longer than wide; parietals paired. Nasals nearly pentagonal, completely divided by nostril, lower and upper sutures clearly visible, nostril central. Loreal 1/1, nearly square; pre-ocular 1/1, much higher than wide; postocular 2/2, upper one slightly larger than lower one. Temporals 2+2+3, two anterior temporals elongated, the upper one smaller in contact with parietal, the lower one in contact with sixth and seventh supralabial; two middle temporals, smaller than anterior temporal; the lower anterior temporal fused with the middle temporal on the right; three posterior temporals. Supralabials 8/8, 1–2 contacting the nasal, 3th to 5th contacting the orbit, 7th largest. One mental. Infralabials 11/13, the first pair in contact blocking the mental from contacting an anterior pair of chin shields.
Two pairs of chin shields. First five on left and first six on right infralabials touching the first pair of chin shields.
Dorsal scales smooth, rhomboid, imbricate, in 23–21–15 longitudinal rows. Vertebral hexagonal and distinctly enlarged, outermost dorsal scale row on both sides smooth and not enlarged. Ventrals 228 (+ 3 preventrals), subcaudals 98 paired, ventral and subcaudal scales strongly angulated laterally, cloacal plate entire.
Colouration in life. The colouration of the specimen's dorsal surface in life is dark brown, with a black stripe distributed almost evenly across the back. The anterior half of the ventral is yellow, while the posterior half gradually becomes white, the edge of the abdomen having small black dots that appear to form a black dotted line when viewed as a whole. The sides of the head have one lateral postorbital stripe, which extends from the last supralabial to the postocular. The pupil is elliptical and black and the sclera is light brown.
Colouration in alcohol. The colouration remains similar to the living specimen, but he anterior half of the ventral gradually turning grayish-white, and the black stripe on the dorsal fades to a yellowish-brown hue.
B. stoliczkae can be differentiated from its congeners by the following combination of morphological characters: 1) mid-dorsum scale rows 21, all dorsal scales smooth; 2) tail length comparatively long, TaL/SVL 24.7-30.5%; 3) supraocular 1; 4) preocular 1; 5) postocular 2; 6) supralabials 8, 1–2 contacting the nasal, 3th to 5th contacting the orbit, 7th largest; 7) infralabials 10-14; 8) Ventrals 222-247; 9) subcaudal paired, 93-120; 10) cloacal plate entire.
B. stoliczkae is mostly semi-arboreal, crepuscular and nocturnal. It is known to inhabit open forest types, agricultural land and human habitations. In our case, the species was found in a road drainage ditch adjacent to the forest edge (Fig.
In order to find the molecular systematic position of the snake in this study, we retrieved cyt b sequences from GenBank for 27 taxa of Boiga and used Telescopus beetzi as the outgroup. The alignment for cyt b was 1015 bp in length.
Maximum Likelihood (ML) methods were used to reconstruct phylogenetic trees (Fig.
Maximum Likelihood (ML) tree inferred from cyt b. Numbers indicate bootstrap support estimated using Maximum Likelihood (1000 pseudoreplicates) analyses. Maximum Likelihood bootstrap supports (BS) are shown at each internal branch. Posterior probability values < 0.70 are not shown.The new record species in the present study are shown in bold.
Genetic distance on cyt b between the specimen of the B. stoliczkae collected from Tibet, China and from GenBank sequence was 1.7%, which is substantially lower than interspecific genetic distances of others (11.5-19.5%) (Suppl. material
In the genus Boiga, intraspecific colouration and pattern polymorphism are known in B. forsteni (Duméril, Bibron & Duméril, 1854), B. multomaculata, B. irregularis (Bechstein, 1802), B. drapiezii (Boie, 1827) and B. dightoni (Boulenger, 1894) (
In China, five species of the genus Boiga have been recorded. Our study reveals that the specimen we collected is the first record of this species in China, thereby broadening its known distribution. Over the years, new reptile species have continually been discovered in the Himalayan Region (
The Himalaya Region is considered a biodiversity hotspot due to its unique geographic and climatic conditions, which have led to the evolution of a diverse range of plant and animal species (
This study was supported by the Second Tibetan Plateau Scientific Expedition and Research Program (STEP), Grant No. 2019QZKK0501, the Key Research and Development Projects of Xizang (XZ202301ZY0036G & XZ202301ZY0019G) and Central-guided Local Projects of Xizang (XZ202301YD0007C).