Hemiphyllodactylus jianfenglingensis, Wang & Yu & Zheng & Zhang & Qi & Jiang & Li & Qi & Song & Yang & Huang & Li & Wang & Wang & Mo & Xie & Li & Wang, 2025

Hemiphyllodactylus jianfenglingensis sp. nov. Wang, Qi, Jiang, Song, Yang, Yu, Li and Wang

Figures 3B View FIGURE 3 , 4B View FIGURE 4 and 6 View FIGURE 6 , Table 6.

Holotype. SYS r002682, adult male, from Mt. Jianfengling , Ledong Li Autonomous County, Hainan Province, China (18.7516°N, 108.9540°E; 510 m a.s.l.) collected on 18 July 2022 by Zhao-Xuan Jiang. GoogleMaps

Paratypes. SYS r002932 and SYS r002933, adult females, from Mt. Jianfengling , Ledong Li Autonomous County, Hainan Province, China (18.6904°N, 108.8618°E; 718 m a.s.l.), collected on 19 January 2025 by Zhong- Bin Yu, and on 27 January 2025 by Hao-Cong Yang, respectively GoogleMaps .

Etymology. The specific epithet “ jianfenglingensis ” is a toponym referring to the type locality of Mt. Jianfengling, Hainan Island.

Common names. Jianfengling Slender Gecko in English; and “尖ḏė半叶DẼ (jiān fēng lǐng bàn yѐ zhǐ hǔ)” in Chinese.

Diagnosis. Hemiphyllodactylus jianfenglingensis sp. nov. can be distinguished from all other congeners by a combination of the following morphological characters: a maximum SVL of 33.8 mm; nine or 10 chin scales; distinctly enlarged postmentals; five circumnasal scales; two or three intersupranasals; nine or 10 supralabials; nine or infralabials; 12–14 longitudinally arranged dorsal scales at midbody contained within one eye diameter and six ventral scales; four subdigital lamellae on the first finger and toe; lamellar formulae (digits II–V) 3-3-3-3 on hands and 3-4-4-4 on feet; 21 continuous, pore-bearing, femoroprecloacal scales in the male; one cloacal spur on each side; no plate-like subcaudal scales; a weak, dark-colored pre- and postorbital stripe extending to at least base of neck; short, dark, rod-like paravertebral markings on trunk; no dorsolateral light-colored spots on trunk; no dark-colored ventrolateral stripe on trunk; light-colored postsacral marking variably bearing anteriorly projecting arms absence; and caecum and gonads unpigmented.

Description of holotype. Adult male, SVL 29.5 mm; head triangular in dorsal view, moderate size (HL/SVL 0.23), length longer than width (HW/HL 0.74), depressed, distinct from neck; snout rounded anteriorly, moderate in length (SN/HL 0.43); lores slightly concave; prefrontal region flat; rostral regular rectangular, wider than mental, bordered posteriorly by first large supranasals; external nares oval, surrounded by rostral, first supralabial, supranasal and two postnasals posteriorly (five circumnasals collectively); three intersupranasals; eye large (ED/HL 0.23), pupil vertical, margins crenulated; ear opening elliptical, obliquely orientated; 10 square supralabials tapering to below posterior margin of orbit; 10 square infralabials tapering to below posterior margin of orbit; scales of rostrum and lores, raised; scales on top of head and occiput small, granular; superciliaries raised, rectangular; mental triangular, bordered laterally by first infralabials and posteriorly by two distinctly enlarged postmentals; 9 chin scales contacting the medial edge of the infralabials and mental from the juncture of the second and third infralabials on both sides; gular scales triangular, small, granular.

Body slender, elongate (AG/SVL 0.56), dorsoventrally compressed; dorsals smooth, round or oval, granular and juxtaposed, 14 scales contained within one eye diameter; ventrals distinctly larger than dorsal scales, flat, imbricate and largest in middle of belly, six scales contained within one eye diameter; precloacal scales not enlarged; pore-bearing precloacal scales continuous with pore-bearing femoral scales, totaling 21 pore-bearing femoroprecloacal scales.

Fore- and hind-limbs short, dorsal surface covered with smooth, granular scales and slightly larger, flat, subimbricate scales on ventral surface; all digits except digit I well-developed, clawed and robustly dilated distally; digit I vestigial, clawless with transversely expanded lamellae, four on both first fingers and first toes; claws on digits II–V well developed, unsheathed; subdigital lamellae of digits II–V divided, angular and U-shaped; lamellae proximal to these transversely expanded, undivided; distal subdigital lamellar formula 3-3-3-3 (fingers II–V) and 3-4-4-4 (toes II–V); relative length fingers and toes I<II<III≈V<IV.

Tail slightly swollen at base, oval in section; caudal scales not occurring in whorls; dorsal caudal scales larger than dorsal body scales, flat, subcycloid, subimbricate; subcaudals slightly larger than dorsal caudals, not plate-like; one enlarged cloacal spur on each side.

Other raw mensural data and ratios are shown in Table 6.

Coloration in life. Ground color of top of head, body, and limbs dusky tan; a distinct dark-colored loreal and postorbital stripe extending to at least base of neck; pupil black; iris yellowish brown with dark brown irregular thin veins; two rows of short, dark, rod-like paravertebral markings on trunk; no dorsolateral light-colored spots on trunk; some dark-colored spots scattered on dorsal head and limbs; light-colored postsacral marking variably bearing anteriorly projecting arms absent; ventral surface of head, body and limbs pale white with tiny black spots; caecum and gonads unpigmented; the coloration of tail dorsum distinct from that of body, yellowish beige in general with some black bands not encircling tail; median subcaudal region bright orange.

Coloration in alcohol. In preservative, dorsal ground color of head, body, and limbs become darker; ventral surface grayish white; subcaudal faded to grayish white; dark spots on dorsal surface blurred.

Comparisons. The molecular analyses indicate that Hemiphyllodactylus jianfenglingensis sp. nov. is embedded within Clade 4. The new species is compared with other species within Clade 4 and with H. khlonglanensis , which is sister to Clade 4 ( Table 7).

In terms of scalation, the new species differs from H. linnwayensis and H. montawaensis by having more chin scales (9 or 10 versus 4–6 and 4–7, respectively); from H. menglianensis by having fewer dorsal scales contained within one eye diameter (12–14 versus 16–18); from H. jinpingensis , H. linnwayensis , H. mengsongcunensis , H. tonywhitteni and H. khlonglanensis by different digital formulas on hands (3-3-3-3 versus (3 or 4)-(4 or 5)-(4 or 5)-(3 or 4), 4-4-4-4, (3 or 4)-(4–6)-(4–7)-(4 or 5), 4-(4 or 5)-(4 or 5)-(4 or 5) and (3 or 4)-4-4-4, respectively); from H. chiangmaiensis , H. linnwayensis , H. mengsongcunensis , H. ywanganensis , H. uga and H. khlonglanensis by different lamellar formulae on feet (3-4-4-4 versus 3-(3 or 4)-3-3, 4-5-(4 or 5)-4, (4 or 5)-(4–6)-(4–6)-(4 or 5), 3-3- 3-3, 3-3-3-3 and 4-4-4-4, respectively); and from H. mengsongcunensis and H. ywanganensis by having fewer total femoroprecloacal pores (21 versus 26–30 and 26, respectively).

In body coloration and pattern, the new species differs from H. chiangmaiensis , H. ngwelwini and H. tonywhitteni by the absence of dorsolateral light-colored spots on trunk (versus presence); from H. linnwayensis , H. montawaensis , H. ngwelwini , H. tonywhitteni , H. ywanganensis and H. uga by the presence of dark dorsal transverse blotches (versus absence); and from H. chiangmaiensis by having unpigmented caecum and gonads (versus pigmented).

In terms of body ratios, the new species differs from H. jinpingensis and H. simaoensis by having a narrower head (HW/HL), a shorter snout-eye length (SN/HL), a shorter nares-eye length (NE/HL) and smaller eyes (ED/HL); and differs from H. menglianensis by having a shorter and wider head (HL/SVL and HW/HL).

On Hainan Island, the new species differs from Hemiphyllodactylus typus by having fewer ventral scales contained within one eye diameter (6 versus 8–10), fewer lamellae on digits II–V of the fingers and toes (3-3-3- 3 and 3-4-4-4 versus 3-4-4-4 and 4-5-5-4), one enlarged cloacal spur on each side (versus one or two small), the absence of dorsolateral light-colored spots on trunk (versus presence) and unpigmented caecum and gonads (versus pigmented); and from H. diaoluoshanensis sp. nov. by more total femoroprecloacal pores (21 versus 15).

Variation. Measurements and scale counts of seven individuals are shown in Table 6. The female individuals have prominently protruding endolymphatic sacs on both sides of the neck ( Figure 4B View FIGURE 4 ).

Distribution and ecology. To date, Hemiphyllodactylus jianfenglingensis sp. nov. is known only from its type locality of Mt. Jianfengling, Ledong Li Autonomous County, Hainan Province, China.

The area surrounding the collection site at the type locality is tropical montane seasonal rainforest.These habitats were also inhabited by other gekkotan species, such as Gehyra mutilata , Gekko similignum and Goniurosaurus bawanglingensis Grismer, Shi, Orlov and Ananjeva, 2002 . The holotype was found on a leaf of a tree approximately 1.5 m above the ground on the side of the road during the evening.

Its reproductive season remains unknown.