Phrynocephalus guinanensis Ji, Wang & Wang, 2009, sp. nov.

Phrynocephalus guinanensis sp. nov.

(Figure 1)

Holotype. NNU (Nanjing Normal University) P 2004.006, adult male (Fig. 1 A, C); Senduo (35 ° 34’N, 101 ° 05’E; altitude 3350 m ASL), Guinan County, Qinghai Province, China; collected by Xiang Ji on 17 May 2004.

Paratypes. NNU P 2004.001-005, NNU P 2004.007-040, 19 adult males and 20 adult females; same data and collector as for holotype.

Etymology. The specific epithet is a latinization of the name Guinan County, Qinghai Province, China.

Diagnosis. A large viviparous species of Phrynocephalus, distinguishable from congeners using the following combination of characters: up to 84 mm SVL; dorsal ground color of head, neck, trunk, limbs and tail brown with weak light brown mottling; lateral ground color of head, neck, trunk and tail light black with weak white-gray mottling in adult males, and green with weak white-gray mottling in adult females; ventral ground color of tail white-gray to black in the distal part of the tail in adult males, and totally white-gray in adult females; ventral surfaces of hind-limbs white-gray; ventral surfaces of fore-limbs brick-red in adult males, and white-gray in adult females; ventral ground color of trunk and head black in the center but, in the periphery, brick-red in adult males and white-gray in adult females, and totally white-gray in adult females; 5 − 8 nasal scales; 5 − 8 internasal scales; 8 − 12 scales around parietal eye; 13 − 18 supraocular scales; 126 − 164 dorsal scales; 101 − 136 ventral scales; 144 − 186 scales around mid-body; 21 − 31 gular folds; 15 − 19 subdigital lamellae of the 4th finger; 22 − 29 subdigital lamellae of the 4th toe (Table 1).

Sexual variation in measurements and scutellation of P. guinanensis sp. nov. is presented in Table 1. It differs from P. vlangalii in all examined morphological traits (Table 1). Moreover, it differs from P. vlangalii, a species with females being the larger sex (Fig. 2; F 1, 388 = 25.89, P <0.0001), in that male and female adults are monomorphic in SVL (Fig. 2; F 1, 207 = 0.03, P = 0.871).

Description of holotype. Adult male (Fig. 1 A, C); SVL 71.7 mm, TL 71.8 mm, HL 18.7 mm, HW 16.5 mm, FLL 23.6 mm, HLL 33.4 mm, FFL 6.8 mm, FTL 10.9 mm, FCL 2.1 mm, TCL 1.8 mm; 7 nasal scales; 7 internasal scales; 10 scales around parietal eye; 13 supraocular scales; 149 dorsal scales; 127 ventral scales; 170 scales around mid-body; 25 gular folds; 15 subdigital lamellae of the 4th finger; 24 subdigital lamellae of the 4th toe; head moderately long (HL/SVL 0.26), wide (HW/HL 0.77), distinct from neck; snout moderately rounded at tip; interorbital region weakly concave; tympanum opening not visible; scales on snout, forehead and dorsum of body small, granular, and nearly homogeneous; body relatively robust; fore-limbs moderately long (FLL/SVL 0.33); hind-limbs more robust and longer (HLL/SVL 0.47) than fore-limbs.

......to be continued N 20 20 20 20 Color of holotype in life. Dorsal ground color of head, neck, trunk, limbs and tail brown with weak light brown mottling (red coloration was not natural but a temporary mark “6” for the holotype); lateral ground color of head, neck, trunk and tail light black with weak white-gray mottling; ventral ground color of trunk and head black in the center, and brick-red in the periphery; ventral ground color of tail white-gray to black in the distal part of the tail; ventral surfaces of fore-limbs brick-red; ventral surfaces of hind-limbs white-gray.

Color variation. In life, adult females (NNU P 2004.021-040) differed in coloration from the holotype in the following four aspects: lateral ground color of head, neck, trunk and tail green with weak white-gray mottling; ventral ground color of trunk and head black in the center, and white-gray in the periphery; ventral ground color of tail totally white-gray; ventral surfaces of fore-limbs white-gray.

Female reproduction. Adult females (N = 14, 65.2 − 78.9 mm SVL) gave birth between late July and early August. Postpartum body mass varied from 8.3 − 15.2 (mean = 11.1) g, litter size from 1 − 4 (mean = 2.1) young, neonate mass from 0.8 − 1.3 (mean = 1.1) g, and litter mass (litter size × neonate mass) from 1.0–4.1 (mean = 2.2) g.

Natural history. At the locality where specimens of P. guinanensis sp. nov. were collected, individuals were abundant in sand dunes with very sparse vegetation consisting of Elymus grasses and man-planted saplings (Genera Salix and Populus). No other known Phrynocephalus lizards in Qinghai resemble P. guinanensis sp. nov. in habitat use. As in numerous other toad-headed lizards, burrows are used to escape predators, or to avoid extreme thermal conditions in P. guinanensis sp. nov.