Opisthotropis maxwelli Boulenger, 1914

Wang, Ying-Yong, Guo, Qiang, Liu, Zu-Yao, Lyu, Zhi-Tong, Wang, Jian, Luo, Lin, Sun, Yan-Jun & Zhang, Yan-Wu, 2017, Revisions of two poorly known species of Opisthotropis Günther, 1872 (Squamata: Colubridae: Natricinae) with description of a new species from China, Zootaxa 4247 (4), pp. 391-412 : 397-399

Opisthotropis maxwelli Boulenger, 1914

Figs. 3 and 6 b

Opisthotropis maxwelli Boulenger, 1914 . Type locality: “South Forkien” (= Fujian)

Specimens examined. Three specimens: SYS r001273, adult female, from Wulong Village (25°12′48.33″N, 116°50′10.69″E; 995 m a.s.l.), Shanghang County, Fujian Province, collected by Jian Wang (JW hereafter), Ying- Yong Wang and Hai-Long He on 16 July 2015 ; SYS r000841, subadult female, from Nan’ao Island (23°26′0.09″N, 117°4′45.61″E; 425 m a.s.l.), collected by Jian Zhao (JZ hereafter) and Yu-Long Li (YLL hereafter) on 30 June 2013 ; SYS r001053, adult male, from Huboliao Nature Reserve (24°34'32.26"N, 117°13'40.61"; 739 m a.s.l.) by Zu-Yao Liu (ZYL hereafter) and Zhi-Tong Lyu (ZTL hereafter) on 22 September 2014 ; further information of collection localities is listed in Table 1 . Five previously collected specimens in buffered formalin from the College of Life Sciences, Fujian Normal University: FJNU 3611 0 0 1, 3611003, 3611004, 3611005 and 3611007, all collected from Nanjing County, Fujian Province, China. The specimens FJNU 3611001, 3611003 and 3611004 were already described by Zhao et al. (1998) and numbered as 1045, 1433 and 561, respectively.

Description. Measurements, scalation and body proportions of six specimens are listed in Table 3. The examined specimens roughly conform to the previous descriptions ( Boulenger 1914; Zhao et al. 1998), and show some variation. Body cylindrical; TL 319–442 mm; tail relatively long, TaL 20–23% of TL; head barely distinct from the neck; snout short, broad and depressed; rostral visible from above, approximately twice as broad as deep, RW 28–32% of HW; nasal directed dorsolaterally, its lower edge inverted V-shaped, bordered by first and second supralabials ventrally, by loreal and prefrontal posteriorly, by internasal dorsally, by rostral anteriorly; a short vertical nasal cleft below the nostril, pointing to the apex angle of first supralabial and dividing nasal into anterior and posterior parts; supralabials 7/7 (n=7), 7/6 (n=1), the first supralabial pentagonal, usually fifth entering the orbit (the fourth entering the orbit in FJNU 3611004, fourth and fifth entering the orbit in right side of head in SYS r001273), the last one (seventh or sixth) longest, longer than total length of two preceding supraliabials; loreal single, 1.4–1.7 times as long as deep, not touching internasal, not entering the orbit, usually in contact with second, third and fourth supralabials (with third and fourth in FJNU 3611001); two (rarely one) preoculars; two postoculars; temporals 1+2/1+2 (n=2), 1+1/1+1 (n=5), 1+1/1+2 (n=1), anterior temporal significantly elongate; infralabials 8/8, first four or five touching anterior chin-shields on both sides; two pairs of chin-shields, the anterior pair large, in contact with each other medially; posterior chin-shields significantly small, separated from each other by small scales; dorsal scale rows 17:17:17; dorsal scales smooth on the anterior neck (dorsal scales on neck smooth in the previous descriptions ( Boulenger 1914; Zhao et al. 1998)), presenting barely perceptible weak keel on sixth vertebral scale in SYS r000841, on ninth vertebral scale in FJNU 3611005 and SYS r001273, on 11th vertebral scale on FJNU 3611004, on 12th vertebral scale in FJNU 3611007, on 15th vertebral scale in FJNU 3611003, on 16th vertebral scale in SYS r001053, succeeding dorsal scales feebly keeled, rather strongly keeled on posterior part of body, but most outer one or two scale rows smooth; V 149–157; cloacal plate divided; subcaudals 54–62, paired (V 147–155, SC 53–61 in descriptions by Zhao et al. (1998)).

Coloration in life. Dorsal surface of head and neck olive-green in SYS r001053 and SYS r001273, with black blotches on each scales; dorsal surface of body and tail olive-green with intermittent longitudinal black stripes parallel to each other, crossing each scale; the outer most dorsal scale row yellow, occasionally with black spots; mental and infralabials black; venter yellow, chin-shields, throat and subcaudal series speckled with black. The specimen SYS r000841 is similar to SYS r001053 in color and pattern in life, but its dorsal surface of head, body and tail dark olive-brown, with 17 bright yellow spots on anterior part of body and barely perceptible longitudinal black stripes, crossing each scale; lower part of the outer most dorsal scale row yellow, with small blackish grey spots; ventral surface yellow, mottled with blackish grey on chin-shields, throat and subcaudal series.

Coloration in preservative. In ethanol, blackish-brown or blackish-grey above, longitudinal stripes of dorsal body visible in SYS r001053, not visible in SYS r000841 and 1273; yellowish beneath. In buffered formalin, brown above, longitudinal stripes distinct, two ventrolateral stripes especially eye-catching; whitish beneath.

Revision of diagnosis. This species is characterized by the combination of (1) TL 319–442 mm; (2) tail relatively long, TaL 20–23% of TL; (3) rostral small, RW 28–32% of HW; (4) nasal in contact with first and second supralabials ventrally; (5) nasal cleft invariably pointing to the apex angle of first supralabial; (6) loreal not entering orbit, 1.4–1.7 times as long as deep; (7) supralabials 6–7, the last one longest; (8) infralabials 8; (9) dorsal scale rows 17:17:17; (10) dorsal scales smooth on the anterior neck, those following feebly keeled, rather strongly keeled on posterior part of body up to the tail; (11) ventrals 147–157, subcaudals 53–62; (12) olive-brown to olivegreen above in life, body and tail with distinct or barely perceptible longitudinal black stripes, crossing each scale; yellow beneath, ventral surface of head and tail mottled with blackish grey.

Distribution and habitat. According to the known specimens and literature ( Boulenger 1914; Zheng 1992, Zhao et al. 1998; Zhong 2004), O. maxwelli is distributed in the southeast of Guangdong Province, the southwest of Fujian Province and south of Jiangxi Province. It inhabits montane slow-flowing streams with sand and gravel bottom at elevations between 425–1000 m a.s.l.

Remarks. Opisthotropis maxwelli was described on the basis of a single female specimen from the British Museum (now the Natural History Museum, London), presented by J. P. Maxwell ( Boulenger, 1914), and specimen number was not given. Zhao et al. (1998) described and measured six specimens of O. maxwelli , of which, specimens FJNU 1433 and 1045 measured at 610 mm and 520 mm in SVL, respectively. However, we obtained measurements of 310 mm and 405 mm in SVL, respectively.

TABLE ³. Measurements (in mm, minimum(maximum [mean ± SD]), scalation anđ bođy proportions of Opisthotropis maxwelli , O. andersonii anđ O. shenzhenensis sp. nov.

Opisthotropis maxwelli Opisthotropis andersonii Opisthotropis shenzhenensis sp. nov.

Figures

FIGURE 3. General aspect of Opisthotropis maxwelli. A and B: Adult male specimen SYS r 001053. C: Dorsolateral view of the subadult female specimen SYS r 000841 in life. D: Adult female specimen SYS r 001273 in life. Photos by JW, JZ and ZYL.

FIGURE 6. Comparisions of head scalation of a: Opisthotropis shenzhenensis sp. nov. (holotype SYS r 001018), b: O. maxwelli (SYS r 000841), c and d: O. andersonii (SYS r 001020, SYS r 001082). Line illustration by ZTL.