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

Hemiphyllodactylus diaoluoshanensis s p. nov. Wang, Qi, Zhang, Zheng, Li, Song, Xie, Li and Wang

Figures 3A View FIGURE 3 , 4A View FIGURE 4 , and 5 View FIGURE 5 ; Table 6.

Holotype. SYS r002862, subadult male, from Mt. Diaoluo , Lingshui Li Autonomous County, Hainan Province, China (18.7096°N, 109.8410°E; 595 m a.s.l.) collected on 19 Apirl 2024 by Hao-Yu Zhang. GoogleMaps

Paratypes. SYS r002863, adult female, data same as the holotype; adult female CIB DLS20220629011 collected from Mt. Diaoluo (18.6959°N, 8800°E; 650 m a.s.l.), Lingshui Li Autonomous County, Hainan Province, China on 29 June 2022 by Pu-Yang Zheng GoogleMaps .

Referred specimen. SYS r002787, juvenile, from Mt. Diaoluo , Lingshui County, Hainan Province, China (18.6771°N, 109.8815°E; 510 m a.s.l.) collected on 7 Apirl 2023 by Mao-Liang Li, only used in molecular analysis, not assigned as type GoogleMaps .

Etymology. The specific epithet “ diaoluoshanensis ” is a toponym referring to the type locality of Mt. Diaoluo, Hainan Island, shan means mountain in Chinese.

Common names. Diaoluoshan Slender Gecko in English; 吊ḆƜ半叶DẼ (diào luó shān bàn yѐ zhǐ hǔ) in Chinese.

Diagnosis. Hemiphyllodactylus diaoluoshanensis sp. nov. can be distinguished from all other congeners by a combination of the following morphological characters: a maximum SVL of 30.4 mm; eight chin scales; distinctly enlarged postmentals; five circumnasal scales; three intersupranasals; nine or 10 supralabials; nine infralabials; 11 or 12 longitudinally arranged dorsal scales at midbody contained within one eye diameter and seven ventral scales; four subdigital lamellae on the first finger and toe; lamellar formulae of digits II–V, 3-3-3-3 on hands and 3-4-4-4 on feet; 15 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; dark short 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. Subadult male, SVL 23.0 mm; head triangular in dorsal view, moderate size (HL/SVL 0.26), length longer than width (HW/HL 0.67), depressed, distinct from neck; snout rounded anteriorly, moderate in length (SN/HL 0.40); 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 0.20), pupil vertical, margins crenulated; ear opening elliptical, obliquely orientated; nine square supralabials tapering to below posterior margin of orbit; nine 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; eight 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 0.50), dorsoventrally compressed; dorsals smooth, round or oval, granular and juxtaposed,11 scales contained within one eye diameter; ventrals distinctly larger than dorsal scales, flat, imbricate and largest in middle of belly, seven scales contained within one eye diameter; precloacal scales nont enlarged;pore-bearing precloacal scales continuous with pore-bearing femoral scales, totaling 15 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. The following description was taken from living specimens photographed in the morning, approximately 12 hours after the time of collection (the same for the species below). 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 the 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 indicated that Hemiphyllodactylus diaoluoshanensis sp. nov. is embedded within Clade 4. The new species is compared with other species within Clade 4 and H. khlonglanensis , which is sister to Clade 4 ( Table 7).

In terms of scalation, the new species differs from H. linnwayensis by having more chin scales (8 versus 4–6); from H. jinpingensis , H. linnwayensis , H. tonywhitteni and H. khlonglanensis by having different lamellar formulae (digits II–V) on hands (3-3-3-3 versus (3 or 4)-(4 or 5)-(4 or 5)-(3 or 4), 4-4-4-4, 4-(4 or 5)-(4 or 5)-(4 or 5) and (3 or 4)-4-4-4, respectively); from H. chiangmaiensis , H. linnwayensis , H. ywanganensis , H. uga , H. mengsongcunensis and H. khlonglanensis by lamellar formulae (digits II–V) on the feet (3-4-4-4 versus 3-(3 or 4)-3-3, 4-5-(4 or 5)- 4, 3-3-3-3, 3-3-3-3, (4 or 5)-(4–6)-(4–6)-(4 or 5) and 4-4-4-4, respectively); from H. menglianensis by having fewer dorsal scales contained within one eye diameter (11–13 versus 16–18); and from H. montawaensis and H. ywanganensis by fewer total femoroprecloacal pores (15 versus 19–21 and 26, respectively).

In body coloration and pattern, the new species differs from H. chiangmaiensis , H. linnwayensis , 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 differs from H. chiangmaiensis by having an 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); from H. mengsongcunensis by having a wider snout width (SW/HW) and from H. linnwayensis and H. ywanganensis by a greater axilla-groin length (AG/SVL).

On Hainan Island , the new species differs from Hemiphyllodactylus typus by having fewer the number of 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) .

Distribution and ecology. To date, Hemiphyllodactylus diaoluoshanensis sp. nov. is currently known only from its type locality of Mt. Diaoluo. Lingshui Li Autonomous County, Hainan Province, China.

The area surrounding the collection site is tropical montane seasonal rainforest.These habitats were also inhabited by other gekkotan species, such as Gehyra mutilata , Gekko similignum Smith, 1923 and Goniurosaurus hainanensis Barbour, 1908 . The holotype was collected from leaves approximately 1.5m above the ground in the evening. The specimen SYS r002787 was found in the gap on the backside of the railing along the roadside, indicating that it is able to use human-made structures, as do many other Hemiphyllodactylus .

Two oval eggs were visible through the skin of the belly (Paratype SYS r002863). This indicates that April falls within the reproductive season of this species.