Cyrtodactylus khelangensis, Pauwels, Olivier S. G., Sumontha, Montri, Panitvong, Nonn & Varaguttanonda, Varawut, 2014

Pauwels, Olivier S. G., Sumontha, Montri, Panitvong, Nonn & Varaguttanonda, Varawut, 2014, Cyrtodactylus khelangensis, a new cave-dwelling Bent-toed Gecko (Squamata: Gekkonidae) from Lampang Province, northern Thailand, Zootaxa 3755 (6), pp. 584-594 : 585-588

Cyrtodactylus khelangensis sp. nov.

( Figs 1–5 )

Holotype. THNHM 22548 (field number MS 409); adult male from a limestone cave in Pratu Pha (99o 49' 30" N, 18o 30' 40" E), Amphoe (= District) Mae Mo, Lampang Province, northern Thailand. Collected by M. Sumontha on 12 July 2008.

Paratypes. PSUZC-RT 2012.9 (MS 278), subadult male. CUMZ-R 0.2318 (MS 410), adult female. Both paratypes collected by M. Sumontha at same locality as holotype.

Diagnosis. Cyrtodactylus khelangensis sp. nov. can be distinguished from all other congeneric species by its maximal known SVL of 95.3 mm; 16–20 longitudinal rows of dorsal tubercles; a continuous series of 37–40 enlarged preanofemoral scales, including six or seven pitted or pore-bearing scales (males) or one or two pitted scales (females) on each femur separated by a diastema from 2–6 pore-bearing preanal scales (males and females); no precloacal groove nor depression; transversely enlarged subcaudal scales; and four irregular brown dorsal bands between nuchal loop and hind limb insertions.

Description of holotype. Adult male. SVL 85.0; TailL 96.0 mm (only 38.8 first mm original). Head long (HeadL/SVL ratio 0.30), moderately narrow (HeadW/HeadL ratio 0.63), not markedly depressed (HeadH/HeadL ratio 0.38), distinct from neck. Loreal region inflated, canthus rostralis not prominent. Snout moderate in length (SnOrb/HeadL ratio 0.38), rounded, longer than orbit diameter (OrbD/SnOrb ratio 0.69); scales on snout small, rounded to oval, granular, larger than those on crown, interorbital and occipital regions. Eye moderately large (OrbD/HeadL ratio 0.26); pupil vertical with crenelated margins; supraciliaries short, those on posterior part of orbit bearing small conical spines. Ear opening vertically elliptical, moderate (EarL/HeadL ratio 0.05); eye to ear distance slightly greater than orbit diameter (OrbEar/OrbD ratio 1.09). Rostral much wider (3.8 mm) than deep (2.2 mm); rostral crease slightly greater than one third rostral height. Two enlarged supranasals in broad medial contact, no internasals. Rostral in contact with first supralabials, nostrils, and supranasals. Nostrils oval, more-or-less laterally directed, each surrounded by supranasal, rostral, first supralabial and three postnasals. Two or three rows of small scales separate orbit from supralabials. Mental triangular, wider (3.8 mm) than deep (2.3 mm). A single pair of greatly enlarged postmentals in broad contact posterior to mental, each postmental bordered anteromedially by mental, anterolaterally by first infralabial, posterolaterally by an enlarged lateral chinshield, and posteriorly by four granular scales. Supralabials to midorbital position 8/8, enlarged supralabials to angle of jaws 11/12. Infralabials 10/9. Interorbital scale rows across narrowest point of frontal bone 27. Gular region with homogeneous, smooth, juxtaposed granular scales.

Body stout, elongate (AG/SVL ratio 0.45) with poorly defined, non-tuberculate ventrolateral folds. Dorsal scales weakly heterogeneous, domed; regularly distributed tubercles (3–5 times size of adjacent scales), extending from shoulder region onto tail base, smaller tubercles on postocular region, crown, occiput and nape; only some medio-dorsal tubercles bearing a (generally poorly defined) keel, especially on posterior trunk and sacral region, other tubercles slightly domed and without keel; tubercles in 16 regular rows at midbody, typically separated from one another by one or two dorsal granules; no tubercles on lower part of flanks. Ventral scales larger than dorsals, smooth, oval and subimbricate, largest on posterior abdomen and in precloacal region. Ventral scale rows between ventrolateral folds 35. A continuous series of 40 enlarged femoroprecloacal scales, as follows, from left to right: one poreless, pitless femoral scale plus six pore-bearing femoral scales plus a diastema of 11 poreless, pitless scales plus five pore-bearing precloacal scales plus a diastema of 10 poreless, pitless scales plus six pore-bearing femoral scales plus one poreless, pitless femoral scale. No precloacal groove nor depression. Postcloacal spurs bearing four/ three enlarged conical scales.

Scales on palm and sole smooth, rounded to oval or hexagonal, slightly domed. Scalation on dorsal surfaces of limbs similar to body dorsum, the anterior lacking, the posterior showing, enlarged conical tubercles interspersed among smaller scales. Fore and hind limbs relatively long, slender (ForeaL/SVL ratio 0.17, TibiaL/SVL ratio 0.19). Digits long, slender, inflected at interphalangeal joints, all bearing robust, slightly recurved claws. Basal subdigital lamellae broad, ovoid to rectangular, without scansorial surface (7-8-8-8-8 right manus, 6-8-8-10 -9 right pes); narrow lamellae distal to digital inflection and not including ventral claw sheath: 9-8 [tip of finger missing]- 9-10- 10 (right manus), 11-10-12-12-12 (right pes); no interdigital webbing. Relative length of digits: IV>III>V>II>I (manus); V>IV>III>II>I (pes). Partly regenerated tail (first 38.8 mm original), long, gently tapering to pointed tip, longer than SVL (TailL/SVL ratio 1.13). Tail with enlarged subcaudal plates, in original and regenerated parts.

Coloration in life. Dorsal ground color of head, body, limbs and tail yellowish. Brown nuchal loop from one orbit to the other, medially interrupted, bordered by yellowish bands. Brown band between orbit and snout, not bordered by yellowish stripes. Four brown bands on dorsum between limbs insertions (plus a half band between first and second bands on the left side), inner parts of interspaces showing irregular areas of the same color as the bands; one similar interspace above sacrum and another on the anterior part of tail, not encircling the tail. Regenerated part of tail light brown, mottled with whitish, underside of tail darker than upper part. Ventral surfaces of head, limbs, belly and cloacal area whitish.

Variation. Main morphometric and meristic characters of the type series are provided in Table 1 . Morphological and coloration characters of the paratypes agree in most respects with those of the holotype, differing only in minor details. In the female paratype CUMZ-R 0.2318, supranasals are separated by an elongate internasal; its continuous series of 40 femoroprecloacal scales is as follows, from left to right: three poreless, pitless femoral scales plus two pitted femoral scales plus a diastema of 12 poreless, pitless scales plus six pore-bearing precloacal scales plus a diastema of 13 poreless, pitless scales plus one pitted femoral scale plus three poreless, pitless femoral scales; its postcloacal spurs each bear two enlarged conical scales. In the subadult male paratype PSUZC-RT 2012.9, supranasals are in contact, being only partly separated by an internasal; the continuous series of 37 femoroprecloacal scales is as follows, from left to right: one poreless, pitless femoral scale plus six pitted femoral scales plus a diastema of nine poreless, pitless scales plus two pore-bearing precloacal scales plus a diastema of 11 poreless, pitless scales plus seven pitted femoral scales plus one poreless, pitless femoral scale. Interspaces between dorsum bands are of the same length to about half the length of the bands, but all known individuals show four band interspaces between limbs insertions. The band interspaces are all bi-colored, their inner part containing more or less extensive surfaces showing the color of the darker bands. Only one individual has a complete tail ( Fig. 4 ) with eight light rings. In all individuals, the first ring is of the same color as the light ground color on dorsum, all other rings are white, and do not encircle the tail.

Distribution and natural history. The species is currently known only from its type locality, a limestone cave in Lampang Province. The types were collected at night, while they were foraging on the cave walls or on boulders at the entrance of the cave. They were found at one to 1.5 meters above the ground. Another individual was observed running on the floor near the cave entrance. Dixonius siamensis (Boulenger) , Gehyra fehlmanni (Taylor) , Gekko gecko gecko (Linnaeus) (Gekkonidae) , Calotes versicolor (Daudin) (Agamidae) and Orthriophis taeniurus helfenbergeri Schulz (Colubridae) were found in the cave or at its entrance, in direct proximity to Cyrtodactylus khelangensis sp. nov.

Etymology. The specific epithet is an adjective derived from Khelang, an old, traditional equivalent name to Lampang. We suggest the following common names: Took-kai Lampang ( Thai), Lampang bent-toed gecko (English) , Cyrtodactyle de Lampang (French), Lampang Bogenfingergecko ( German), Lampangkromvingergekko (Dutch).

Figures

FIGURE 1. Dorsal view of preserved type series of Cyrtodactylus khelangensis sp. nov. (from top to bottom: adult male holotype, adult female paratype, subadult male paratype). Photo. by O. S. G. Pauwels.

FIGURE 2. Ventral view of preserved type series of Cyrtodactylus khelangensis sp. nov. (from top to bottom: adult male holotype, adult female paratype, subadult male paratype). Photo. by O. S. G. Pauwels.

FIGURE 3. Live adult Cyrtodactylus khelangensis sp. nov. from type locality, not preserved. Photo. by M. Sumontha.

FIGURE 4. Second live adult Cyrtodactylus khelangensis sp. nov. from type locality, not preserved. Photo. by M. Sumontha.

FIGURE 5. Third live adult Cyrtodactylus khelangensis sp. nov. from type locality, not preserved. Photo. by M. Sumontha.