Cyrtodactylus panitvongi Pauwels & Chotjuckdikul & Donbundit & Sumontha & Meesook 2024, sp. nov.

Cyrtodactylus panitvongi sp. nov. (Figures 1–6) Holotype. CUMZ-R-2596 (field no. MS 757), adult male caught on 27 December 2022 in Tham (= Cave) Khao Chan, Wat (= Temple) Tham Khao Chan (14°58’42.2”N, 101°18’40.6”E), Tha Luang District, Lopburi Province, central Thailand, by Nonn Panitvong, Natthaphat Chotjuckdikul, Saranon Charoensuk, Natthasuda Donbundit and Montri Sumontha. Paratypes (3). CUMZ-R-2597 (field no. MS 758), adult male, and CUMZ-R-2594–2595 (field nos. MS 759 and MS 760, respectively), adult females; same locality, date and collectors as for the holotype. Diagnosis. Cyrtodactylus panitvongi sp. nov. can be distinguished from all other congeneric species by the combination of its maximal known SVL of 85 mm, 15–18 interorbital scales, 35–37 interciliary scales, 10–12 supralabials, 9–11 infralabials, 29–33 paravertebral tubercles of which 22–25 between limb insertions, 18 longitudinal rows of dorsal tubercles at midbody, 40–42 ventral scale rows at midbody, poorly defined, non-denticulate ventrolateral folds, a series of 13 or 14 enlarged femoroprecloacal scales including 2 pores on the proximalmost scales on each side separated by a single smaller medial scale in males, or six precloacal pits on a continuous series of 32–34 enlarged femoroprecloacal scales in females, no precloacal groove or depression, two or three postcloacal spurs on each side of the base of the tail in males and females, no interdigital webbing, 16–19 total subdigital lamellae on 4th toe, a row of widened median subcaudal plates, a banded dorsal pattern including an uninterrupted nuchal collar and three dark bands on dorsum, 10 or 11 dark-colored rings on original tail, and a golden iris. Description of the holotype. Adult male (Figures 1, 2 & 5). SVL 74.0 mm. TailL 93.3 mm, tail original and complete. Head relatively long (HeadL/SVL ratio 0.30), wide (HeadW/HeadL ratio 0.66), not markedly depressed (HeadD/HeadL ratio 0.43), distinct from slender neck. Loreal region inflated, canthus rostralis not prominent. Snout elongate (SnOrb/HeadL ratio 0.41), rounded, longer than orbit diameter (OrbD/SnOrb ratio 0.85); scales on snout small, rounded to oval, granular, mostly homogeneous, larger than those on crown, interorbital and occipital regions. Eye large (OrbD/HeadL 0.35); pupil vertical with crenelated margins; supraciliaries short, bearing small conical spines. Ear opening rounded, small (EarL/HeadL 0.04); orbit to ear distance smaller than orbit diameter (OrbEar/OrbD 0.81). Rostral much wider (3.8 mm) than deep (2.0 mm), rostral crease about half of rostral height. Two enlarged supranasals separated from one another by two small superposed scales. Rostral in contact with first supralabials, nostrils, supranasals and internasal. Nostrils oval, more or less laterally directed, each surrounded by supranasal, rostral, first supralabial and three postnasals. Three or four rows of small scales separate orbit from supralabials. Mental triangular, distinctly wider (2.9 mm) than deep (1.8 mm). A single pair of greatly enlarged postmentals in broad contact behind mental, each bordered anteromedially by mental, anterolaterally by first infralabial, posterolaterally by an enlarged lateral chinshield; both postmentals collectively bordered posteriorly by three gular scales. Supralabials to mid-orbital position 8/7, enlarged supralabials to angle of jaws 10/11. Infralabials 11/10. Interorbital scale rows across narrowest point of frontal bone 18. Body slender, moderately short (AG/SVL 0.39; TrunkL 43.5 mm) with poorly defined, non-denticulate ventrolateral folds. Dorsal scales relatively homogeneous, domed; dorsal tubercles about five times size of adjacent dorsal scales, extending from nape onto tail, smaller tubercles on postocular region, crown, occiput and nape; most tubercles bearing a strong keel, less marked on lower flank tubercles; tubercles on posterior trunk and sacral region most prominent; tubercles in 18 rows at midbody, separated from one another by two to four, but generally three, dorsal granules. Ten or 11 granular dorsal scales surround each tubercle. Ventral scales larger than dorsals, smooth, oval and subimbricate, largest on posterior abdomen and in precloacal region. Midbody scale rows across belly between ventrolateral folds 42. Gular region with homogeneous, smooth, juxtaposed granular scales. No precloacal groove or depression. On each side a continuous series of 13 enlarged femoroprecloacal scales, the two proximalmost bearing each a pore; the two series separated by a diastema of one poreless medial scale. Postcloacal spurs each bearing two enlarged, conical scales. Scales on palm and sole smooth, rounded to oval or hexagonal, slightly domed. Scalation on dorsal surface of hind and forelimbs similar to body dorsum with enlarged tubercles interspersed among smaller scales. Fore- and hind limbs relatively long, slender (FaL/SVL 0.15, TibL/SVL 0.21). Digits long, slender, inflected at interphalangeal joints, all bearing robust, slightly recurved claws. Basal subdigital lamellae broad, oval to rectangular, without scansorial surfaces (5-4-4-5-6 right manus, 3-4-5-6-6 right pes); narrow lamellae distal to digital inflection and not including ventral claw sheath: 10-12-12-10-11 (right manus), 10-11-13-12-15 (right pes); no interdigital webbing. Relative lengths of digits: IV>III>V>II>I (manus), IV>V>III>II>I (pes). Tail original and complete, gently tapering to pointed tip, distinctly longer than SVL (TailL/SVL ratio 1.26). A single median row of enlarged subcaudal plates. In life, dorsal ground color of head, dorsum and limbs light olive brown. Poorly marked reticulations on head. Area above orbits bluish. A brown continuous nuchal loop, pursuing a brown preorbital stripe, connects orbits. Three brown bands on dorsum, longer than their light interspace, the anterior one beginning above the shoulder; the anterior and posterior borders of the collar and these brown bands black; numerous black irregular marks on the light interspaces (Figure 1). Irregular thin, black bars on upper surface of limbs, hands and feet. Background color of anterior part of tail olive brown as dorsum, turning to white posteriorly, with ten dark rings (dark brown anteriorly, turning to black posteriorly), encircling the tail; irregular black marks on the light interspaces between the dark rings. Iris golden. Supralabials, infralabials, throat, venter and undersides of fore- and hind limbs uniformly whitish. Variation. Main morphometric and meristic characters of the type series are provided in Table 1. Similarly to the holotype, ten or 11 granular dorsal scales surround each tubercle in the paratypes. While both males show four precloacal pores separated by a diastema of one scale, both females have a continuous series of six pitted precloacal scales, and more enlarged femoroprecloacal scales (32–34 versus 26–28). Besides the holotype, only one other type, the female CUMZ-R-2595, has a complete, original tail, with a TailL/SVL ratio of 1.08, thus proportionally a bit shorter, and ten dark rings (Figure 5). The reticulate pattern on the head is more marked on two paratypes (CUMZ-R-2594 and CUMZ-R-2597; Figures 3 and 4) than in the holotype. The only known juvenile shows a pattern similar to that of the adults, but more contrasted, with 11 dark rings on tail (Figure 6). The regenerated parts of tail show no more rings, but a light to dark brown background color mottled with black, above and below, and no more widened subcaudals. Distribution and natural history. All adult individuals observed, including the type-series, were found at night within the twilight zone and the entrance zone of Khao Chan Cave or just outside its entrance. Several juveniles were observed, all just outside the cave. Cyrtodactylus panitvongi sp. nov. is a trogloxene species (sensu Jantarit & Ellis 2023) with a karst ecotype (sensu Grismer et al. 2020b, 2021c). It is so far known only from its type-locality (Figures 7 and 8). Within the cave, near its entrance, it was observed with the reptiles Calotes versicolor (Daudin) (Agamidae), Dixonius siamensis (Boulenger), Gehyra wongchan Pauwels, Meesook, Kunya, Donbundit & Sumontha, Gekko gecko (Linnaeus), G. pradapdao Meesook, Sumontha, Donbundit & Pauwels, Hemidactylus frenatus Duméril & Bibron, H. platyurus (Schneider) (Gekkonidae), Lycodon capucinus Boie, L. davisonii (Blanford) (Colubridae) and Trimeresurus macrops Kramer (Viperidae), and the amphibians Duttaphrynus melanostictus (Schneider) (Bufonidae) and Polypedates megacephalus Hallowell (Rhacophoridae). Just outside the cave entrance, it was found with the amphibians Microhyla heymonsi Vogt (Microhylidae) and Fejervarya limnocharis (Gravenhorst) (Ranidae). Etymology. The specific epithet honors our friend, the Thai zoologist, conservationist and photographer Nonn Panitvong, for his contributions to the knowledge of the fauna of the Kingdom of Thailand. We suggest the following common names: ตุ๊กกายถ้ำลพบุรี (Took-kai-tham-Lopburi; Thai), Lopburi Bent-toed Gecko (English), and Cyrtodactyle de Lopburi (French). Comparison to other species. Cyrtodactylus panitvongi sp. nov. is readily distinguishable from C. cardamomensis Murdoch, Grismer, Wood, Neang, Poyarkov, Ngo, Nazarov, Aowphol, Pauwels, Nguyen & Grismer, C. intermedius Smith, C. kulenensis Grismer, Geissler, Neang, Hartmann, Wagner & Poyarkov, C. thylacodactylus Murdoch, Grismer, Wood, Neang, Poyarkov, Ngo, Nazarov, Aowphol, Pauwels, Nguyen & Grismer and other members of the C. intermedius complex by the presence of numerous black marks on the light interspaces on dorsum and tail (versus absence of black marks), and by the absence (versus presence) of a dotted line of white tubercles outlining the dark dorsal bands (see Murdoch et al. 2019 and Grismer et al. 2020a, 2021a, 2023a). By its discontinuous series of 4 PrePo in males, it is moreover distinguished from Cyrtodactylus cardamomensis (9 or 10 PrePo in a continuo