A new species of the genus Hebius (Squamata: Colubridae) from Sichuan, China Author Liu, Qin Author Zhong, Guang-Hui Author Wang, Ping Author Liu, Yang Author Guo, Peng text Zootaxa 2018 2018-09-21 4483 2 385 394 journal article 29513 10.11646/zootaxa.4483.2.10 5b0dfb7c-9e7e-4e3e-b438-5e25073759ba 1175-5326 1437631 0618503B-5824-4A23-980D-317A4B5DFAF4 Hebius yanbianensis sp. nov. ( Figs. 3–7 ) Holotype . YBU 15018, an adult male, collected by Guanghui Zhong and Ping Wang in March 2015 in Zemulong Town , Yanbian County ( N 101°35′04.43″ , E 27°13′52.00″ ), South Sichuan Province , China , at an elevation of 1, 974 m above sea level . FIGURE 3. General view of the holotype of Hebius yanbianensis sp. nov. (YBU 15018) in life. Photo by G.H. Zhong. FIGURE 4. Dorsal (top) and ventral (bottom) views of the holotype of Hebius yanbianensis sp. nov. (YBU15018) in preservative. Photo by P. Guo. Diagnosis. Hebius yanbianensis sp. nov. can be distinguished from its congeners on the basis of the following combination of characters: 1) TL/SVL ratio 0.35; 2) three postoculars; 3) six temporals in formula 1/(1+1) +1+2; 4) eight supralabials, 4th and 5th in contact with the eye, 6th largest;5) ten infralabials, the first five bordering the anterior chinshields; 6) 172 ventrals (plus one preventral); 7) cloacal plate divided; 8) 90 pairs of subcaudals; 9) dorsal scales in 19-19-17 rows, all weakly keeled except the outer two; 10) reduction of dorsal scale rows from 19 to 17 scale (VS19TO17) at the position above 99th ventral scale; 11) reduction of the dorsal tail scales from 8 to 6 scale rows (SC8TO6) at the ventral position of 18th subcaudal, and from 8 to 6 (SC6TO4) at the position above 37th subcaudal; 12) postorbital bones not touching frontals, the parietal ridge weakly developed; the end of the supratemporal bones extending beyond the braincase; maxillary teeth 23-25, the last two distinctly enlarged without diastema between the last two and the anterior teeth. Description of holotype . A male specimen with SVL 420 mm ; tail complete, TL 145 mm , TL/SVL 0.35. FIGURE 5. Dorsal (A), ventral (B), and lateral (B) views of the head of the holotype of Hebius yanbianensis sp. nov. in preservative. Photo by P. Guo. Head distinct from neck. Rostral visible dorsally. Internasals subtriangular, wider than long. Prefrontals large, extending laterally onto sides of head. Frontal longer than wide. Supraoculars broadly in contact with prefrontals, with supraoculars two-thirds as broad as frontals. Single loreal long, rectangular. Preoculars 2/2, postoculars 3/3. Six temporals, formula 1/(1+1) +1+2 on both sides, anteriorly one long, above 2 short + 1 long + 2 posterior temporals. Supralabials 8/8, the 4th and 5th bordering orbit. Infralabials 10/10, the first 5 in contact with anterior chinshields. Nostrils lateral, nasals undivided. In life, dorsum and upper surface of taildark gray with numerous dorsal scales edged in bright yellow, especially on the sides of the forepart of the body, making the body strongly flecked with yellow; the upper surface of the body less flecked; in posterior part of the body, yellow flecking less conspicuous and limited to aligned blotches on the sides. The abdomen milk-white with a large, black, triangular blotch near the outer end of each ventral, these spots forming a strongly marked ventrolateral series. Dorsal scale rows 19-19-17, all feebly keeled except the outer two rows. Reduction from 19 to 17 dorsal scale rows at the position of the 2nd and 3rd dorsal scale rows and between the 96th and 101 st ventrals . Ventrals 172 plus 1 pre-ventral. Subcaudals 90, paired. Cloacal divided. The scale rows reduction formula on the tail: 5(2 + 3) 18(3 + 4) 36(2 + 3) 10 8 6 4 6 ( 2 + 3 ) 17 ( 3 + 4 ) 38 ( 2 + 3 ) The skull of the holotype ( Fig. 6 ) displays a generalized colubrid pattern ( Cundall 1981 ). Nasals tend to be triangular. Prefrontals are large with medial dorsal process. Frontal is about twice longer than wide. Large postorbits do not touch frontals. Parietals show to be bowed outward, with its end extending beyond the braincase. The quadrates are much broader anteriorly than posteriorly. There are 23–25 maxillary teeth on both sides, the last two are distinctly enlarged, without diastema between the last two and the anterior teeth. There are about 30 teeth on both sides of dentary. FIGURE 6. Dorsal (A), ventral (B) and lateral (C) views of CT scanned skull of the holotype of Hebius yanbianensis sp. nov. Natural history. The specimen was collected on an ecological transition belt between farmland and evergreen forest ( Fig. 7 ). No data on diet and reproduction is available. Etymology. The specific name refers to the type locality of this species, Yanbian County, Sichuan . We suggest the following common names: Yanbian Fulianshe ( ÊṸȒřẘ ) and Yanbian keelback snake (English). Distribution. This species is currently known only from the type locality, Yanbian ( Fig.1 ) that is located in the Hengduan Mountains valley in Sichuan Province , China with dry-hot climate.