Lycodon maculatus comb. nov. (Cope, 1985)

Liu, Shuo, Hou, Mian, Cai, Bo, Li, Shimin, Zhang, Zhongxu, Yu, Rui, Rao, Dingqi & Zhang, Liang, 2023, Taxonomic status of Lycodon subcinctus sensu lato in China (Serpentes, Colubridae), Herpetozoa 36, pp. 307-316 : 307

Lycodon maculatus comb. nov. (Cope, 1985)

Figs 2 , 3

Type material.

Holotype. USNM 7339, adult male.

Type locality.

Hong Kong Special Administrative Region, China.

Diagnosis.

Body size relatively small, slender; 17-17-15 dorsal scale rows; eight supralabials, 3rd-5th or 3rd-6th contacting eye; 8-9 infralabials; no preocular; prefrontal contacting eye; two postoculars; one loreal contacting eye; one anterior temporal and two posterior temporals in most individuals; ventral scales less than 205; subcaudal scales more than 70, paired; cloacal plate divided; dorsal scale feebly keeled; anterior part of head dark grey or black; posterior lateral parts of head white in juveniles and dark gray or grayish black in adults; 20-27 distinct white bands on dorsal body and tail in juveniles; 5-8 grayish white bands gradually blur backward on anterior part of body in adults; no bands on posterior part of body and tail in adults.

Redescription of the holotype.

Head flattened, somewhat elongate, HL 17.1 mm, HW 9.3 mm, HH 6.7 mm, HL/HW 1.84, HW/HH 1.39, distinct from the neck; snout relatively elongate, SnL 5.4 mm, SnL/HL 0.32, nostril closer to snout than to eye, internarial distance large, InD 4.2 mm, InD/HW 0.45; eye moderately sized, ED 2.0 mm, ED/HL 0.12, with a nearly rounded pupil; rostral approximately triangular, visible from above; two nearly triangular internasals; two large parallelogram-like prefrontals; single shield-shaped frontal; two large, elongate parietals; 1\1 nearly trapezoidal supraocular; no preocular; 2\2 small postoculars, upper one slightly larger than lower one; 1\1 narrow, elongate loreal entering orbit, in contact with nasal anteriorly, prefrontal dorsally, second and third supralabials ventrally; 8\8 supralabials; first and second supralabials in contact with nasal; third, fourth, and fifth supralabials in contact with eye; 1\1 anterior temporal; 2\2 posterior temporals; 8\8 infralabials; first pair infralabials contact medially forming a deep, medial groove; first three infralabials in contact with first pair of chinshields; first pair of chinshields elongate, bearing a deep, medial grooves contiguous with groove separating first pair of infralabials.

Body slender; SVL 428 mm; tail incomplete; 191 ventrals; cloacal plate divided; dorsal scales in 17-17-15 rows; vertebral row not enlarged; no apical pits.

After long-term immersion in preservative, head almost entirely white with a little light reddish brown on top; dorsal surface of anterior body reddish brown with seven white bands, first six distinct and last one indistinct; dorsal surface of posterior body and tail pale brown with no bands; ventral surface of head, body, and tail white.

Other specimens examined.

We examined eight specimens in Kunming Natural History Museum of Zoology , Kunming Institute of Zoology , Chinese Academy of Sciences (KIZ) and two specimens in Museum of Herpetology , Chengdu Institute of Biology , Chinese Academy of Sciences (KIZ CIB). KIZ2009061301, adult male, from Tian’e County, Hechi City , Guangxi Autonomous Region , China (Exact locality unknown); KIZ20190902, adult female, from Leyi Village , Chuanshan Town , Huanjiang County , Hechi City , Guangxi Autonomous Region , China (25°5'56"N, 108°0'9"E, at an elevation of 570 m); KIZ2023029, adult female, from Huangpu District , Guangzhou City , Guangdong Province, China (23°5'45"N, 113°16'52"E, at an elevation of 200 m); KIZ2023030, adult female, from Hanjiang District , Putian City , Fujian Province, China (Exact locality unknown); KIZ2023031, adult male, from Menglun Town , Mengla County , Xishuangbanna Prefecture , Yunnan Province, China (21°56'9"N, 101°15'10"E, at an elevation of 550 m); KIZ2023032, adult male, from Luohu District , Shenzhen City , Guangdong Province, China (22°34'7"N, 114°14'9"E, at an elevation of 240 m); KIZ2023034, adult male, from Jinghong City , Xishuangbanna Prefecture , Yunnan Province, China (Exact locality unknown); KIZ2023044, juvenile, from Xiegang Town , Dongguan City , Guangdong Province, China (22°54'20"N, 114°14'19"E, at an elevation of 260 m); and KIZ CIB 78124 and KIZ CIB 9820, two adult females, both from Sanya City, Hainan Province, China (Exact locality unknown) (Fig. 4 ) .

Variation.

The morphological data of other specimens are presented in Table 2 . All specimens resemble the holotype except that third, fourth, fifth, and sixth supralabials contact eye in some individuals, anterior and posterior temporals vary from one to two, nine infralabials in some individuals, first four infralabials in contact with first pair of chinshields, ventrals vary from 189 to 203, subcaudals vary from 71 to 84, and the bands on dorsal body vary from five to eight in adults and 14 bands on dorsal body and 12 bands on dorsal tail in the juvenile.

Morphological comparison.

Lycodon maculatus comb. nov. differs from L. subcinctus by having fewer ventral scales, namely less than 205 vs. more than 205. Lycodon maculatus comb. nov. differs from L. sealei by subcaudal scales more than 70 vs. less than 70. In addition, the number of bands on dorsal body and tail is significantly different, although the bands become indistinct in adults, they are usually distinct in juveniles. According to the figures in Siler et al. (2013), Leviton et al. (2018), Francis (2021), and Huang (2021), and Fig. 3F and Table 2 in this paper, the total number of bands on dorsal body and tail of juveniles is less than 15 in L. sealei and more than 40 in L. subcinctus , whereas the number is 20-27 in Lycodon maculatus comb. nov.

Distribution.

Lycodon maculatus comb. nov. is currently known to be distributed in southern China and Nakhon Ratchasima, Thailand. As Nakhon Ratchasima is located in central southern Thailand and the nearest confirmed distribution site of Lycodon maculatus comb. nov. is in Xishuangbanna, Yunnan, China, it can be assumed that the species is likely to occur in the area between Nakhon Ratchasima and Xishuangbanna, specifically in northern Thailand and central and northern Laos. In addition, it is likely that the population in northern Vietnam, previously considered to be L. subcinctus , also belongs to Lycodon maculatus comb. nov.

Figures

Figure 2. The holotype (USNM 7339) of Lycodon maculatus comb. nov. in preservative. A. Dorsal view; B. Ventral view. Photos are obtained from the website of National Museum of Natural History. Photographer: Teresa Hsu from Division of Amphibians & Reptiles, National Museum of Natural History, Smithsonian Institution.

Figure 3. Lycodon maculatus comb. nov. from China in life. A. The adult female (KIZ 20190902) from Hechi City, Guangxi Autonomous Region; B. The adult female (KIZ 2023029) from Guangzhou City, Guangdong Province; C. The adult female (KIZ 2023030) from Putian City, Fujian Province; D. The adult male (KIZ 2023031) from Xishuangbanna Prefecture, Yunnan Province; E. The adult male (KIZ 2023032) from Shenzhen City, Guangdong Province; F. An uncollected juvenile from Qingyua City, Guangdong Province.

Figure 4. Map showing the type locality of Lycodon maculatus comb. nov. in Hong Kong Special Administrative Region, China (1) and the localities of the specimens examined in this study (2 - 8).