Gekko alpinus, Ma & Shi & Shen & Chang & Jiang, 2024

Ma, Shun, Shi, Sheng-Chao, Shen, Cheng, Chang, Li-Ming & Jiang, Jian-Ping, 2024, Discovery of a new species of the subgenus Japonigekko (Squamata, Gekkonidae, Gekko) from the Hengduan Mountains, southwestern China: the best Japonigekko mountaineer, ZooKeys 1215, pp. 289-309 : 289-309

Gekko alpinus sp. nov.

Figs 4 , 5 , 6 , 7

Type materials.

Holotype. • CIB 121663 (Figs 4 , 5 ), an adult male, collected 26 June 2020 (29.615722 ° N, 99.02285 ° E; 2542 m a. s. l.), from Zhubalong Village , Batang County, Ganzi Zang Autonomous Prefecture, Sichuan Province, China by Sheng-Chao Shi, Cheng Shen, Xian-Guang Guo, and Jian-Ping Jiang . Paratypes. • One adult male: CIB 121661 , four adult females: CIB 121658–60 , and CIB 121664 , and one subadult female: CIB 121662 , with the same collection information as the holotype • One adult male: CIB 121665 and one subadult female: CIB QZ 088 collected 29 June 2020 (29.731613 ° N, 99.002355 ° E; 2494 m a. s. l.), with the same collection locality and collectors’ information • One adult male: CIB 121656 and one subadult female: CIB 121657 (Fig. 6 ) collected 7 July 2022 (29.758142 ° N, 99.005975 ° E; 2400 m a. s. l.), from Zhubalong Village , Mangkang County, Changdu City, Xizang Autonomous Region, China by Cheng Shen, Li-Ming Chang, and Qun-De Zhang .

Diagnosis.

(1) body size moderate, SVL 56.44–74.16 mm in adults; (2) head relatively narrow, HW / HL 0.51–0.79; (3) midbody scale rows 92–114, 98–114 in males and 92–106 in females; (4) interorbital scales between anterior corners of the eyes 22–28; (5) ventral scale rows 32–39; (6) tubercles present on dorsal body, forelimbs, hindlimbs and tails; (7) precloacal pores 4–7 in males and absent in the females; (8) subdigital lamellae on first finger 8–11, on fourth finger 12–14, on first toe 8–11, on fourth toe 12–15, no webbing between the fingers and toes; (9) ventral scales between mental and cloacal slit 158–189; (10) nares in contact with rostral; (11) postcloacal tubercles one or two; (12) dorsal surface of body with six or seven large dark taupe bands between nape and sacrum.

Description of holotype.

(Figs 3 , 4 ) An adult male, moderate size, SVL 74.16 mm; body slender and trunk relatively elongate (AGD / SVL 0.37); tail little broken at end, TaL 68.02 mm, slightly shorter than SVL.

Head depressed (HH / HL 0.37), length longer than width (HL / HW), distinct from neck. Snout rounded at top, elongate (SL / HL 0.41 / 0.42), larger than eye (SL / ED 1.75 / 1.80); rostral irregular polygon, wider than high (RW / RH 1.74) and slightly narrower than mental (RW / MW 0.95); rostral groove absent; rostral in contact with nostril, first supralabial and nasorostral; nares oval, touching rostral, first supralabial three nasals (nasorostral, supranasal, postnasal); one small internasal; snout region medially concave; preorbitals 12 / 12, preorbital region deeply concave; eye large ( ED / HL 0.24 / 0.23), pupil vertical with crenulated margins; interorbital scales between anterior corners of eyes 27; ear opening oval, obliquely oriented, much smaller than eye ( EOD / ED = 0.27 / 0.26); mental pentagon, width more than length ( MW / ML = 0.73); two enlarged postmentals, hexagonal, twice as long as wide; postmentals in contact with mental and first infralabials anteriorly and five gular scales posteriorly; supralabials 11 / 11; infralabials 10 / 10; tubercles absent on dorsal head, granulars on anteriodorsal head larger than those on posterior.

Dorsal scales on body smooth, round or oval, granular, juxtaposed; dorsal tubercles 3–4 times the size of dorsal scales, smooth, round to oval, convex, surrounded by 8–10 dorsal scales; dorsal tubercles extending from occiput region to base of tail; tubercles in 15 regular rows at midbody; ventrolateral fold weakly developed, without tubercles; ventrals distinctly larger than dorsal scales, smooth, imbricate and largest in middle of belly; ventral scale rows at midbody 33; scale rows around mid-body 114; ventral scales in a row between mental and cloacal slit 165; precloacal scales enlarged, but no enlarged scales on thighs; precloacal pores seven, in a continuous row.

Forelimbs and hindlimbs well developed, tubercles on fore and hind limbs are present, moderately long, slender; forearm and tibia moderately long, forearm shorter than tibia; digits moderately expanded, both first finger and first toe, clawless, others remaining digits clawed; webbing on fingers and toes absent; subdigital lamellae unnotched and undivided: 10 / 10-9 / 10 - 11 / 10 - 13 / 13 - 11 / 11 (manus) and 11 / 10-11 / 10 - 12 / 12 - 15 / 14 - 13 / 13 (pes). Relative length of fingers: IV> III> V > II> I; relative length of toes: IV> III> V > II> I.

Tail oval in section, swollen at base, gradually tapering; postcloacal tubercle 1 / 1, obviously large on tail base side; dorsal scales small, flat, smooth, with dorsal tubercles at the tail base dorsum; ventral scales much larger than dorsal, smooth, and imbricated, with enlarged subcaudal plates arranged into a longitudinal row formed ~ 1 / 6 TaL distance from the cloaca.

Coloration of holotype in life.

(Figs 4 , 5 ). Dorsal surfaces of head, neck and body dark taupe, irregularly scattered with some pale grey threads or blotches, alternatively ornamented with eight large pale grey and seven dark taupe wide bands from neck to the sacrum; an indistinct pale-colored vertebral line is present from the nape to the tail base; dorsal surfaces of limbs, also dark taupe, mottled with small and pale blotches; dorsal tail dark taupe, alternatively ornamented with nine large pale grey and nine larger dark taupe bands, mottled at the ends; ventral skin creamy white, mosaiced with small taupe pigments.

Coloration of holotype in preservative.

The coloration pattern of the specimen mostly faded. Dorsal surfaces of head, neck, and body black taupe, but compared to the living status, much wider body area irregularly creamy white, and still alternatively ornamented with eight large creamy white and seven black taupe wide bands from neck to the sacrum. A creamy white vertebral line extends from the nape to the tail terminal; dorsal surfaces of limbs creamy white, mottled with small taupe blotches; dorsal tail dark taupe, alternatively decorated with nine large creamy white and nine larger taupe bands, and mottled towards the end. Ventral skin creamy white, mosaicked with small taupe pigments, though some areas turned creamy yellow due to prolonged alcohol storage.

Variation.

All paratypes are very similar to the holotype. Variation of the mensural characters and meristic features among individuals of the type series are presented in Table 4 .

Distribution and habits.

Gekko alpinus sp. nov. is currently known only from the Jinsha River Basin between the border of Mangkang County, Xizang Autonomous Region and Batang County, Sichuan Province, China, at elevations ranging from 2400 to 2542 meters above sea level. This new species is nocturnal and inhabits shrubs or dry rocky cliffs in the arid Jinsha River valley, as well as on building walls (Fig. 7 ). Ants, discovered in the gut of one specimen, are among the recorded food choices of this species.

Etymology.

The specific name alpinus is derived from Latin, alpinus , - a, - um, meaning from Alpēs (“ the Alps ”) + - īnus, of or pertaining to the Alps, alpine. This refers to the “ great high mountains ”, referring to not only its distribution range in the great high Hengduan Mountains, but also the highest distribution elevation for all currently known Japonigekko species. The suggested common English name is “ Alpine Gecko ” and the Chinese name is “ 高山壁虎 ” (Gāo Shān Bì Hŭ).

Figures

Figure 3. Principal component analysis performed for Gekko alpinus sp. nov. and G. jinjiangensis based on 12 commonly used morphological traits (except SVL, Tal, FIL, HIL). Numbers inside the brackets indicate the percentages of the total variance explained by each axis.

Figure 4. Holotype (CIB 121663, adult male) of Gekko alpinus sp. nov. A dorsal view of body B ventral view of body. Photographs by S-C Shi.

Figure 5. Holotype (CIB 121663, adult male) of Gekko alpinus sp. nov. A right lateral view of head B dorsal view of head C ventral view of body D dorsal view of middle body E ventral view of precloacal region F ventral view of left hand G ventral view of left foot. Photographs by S-C Shi.

Figure 6. Paratype (CIB 121657, subadult female) of Gekko alpinus sp. nov. A dorsal view of body B ventral view of body C dorsal view of head D ventral view of head E dorsal view of middle body F ventral view of precloacal region. Photos by S Ma.

Figure 7. Habitats of Gekko alpinus sp. nov. A macrohabitat: Jinsha River dry-hot valley in Zhubalong Village at the border between Batang County, Sichuan Province and Mangkang County, Xizang Autonomous Region B microhabitat: house walls C one individual found on the dry rocky cliffs D one individual found in the rock crevices on cliff E one individual found on a house wall. Photos by S-C Shi.