Cyrtodactylus kamengensis, Mirza & Bhosale & Thackeray & Phansalkar & Sawant & Gowande & Patel, 2022

Mirza, Zeeshan A., Bhosale, Harshal S., Thackeray, Tejas, Phansalkar, Pushkar, Sawant, Mandar, Gowande, Gaurang G. & Patel, Harshil, 2022, A new species of bent-toed geckos of the genus Cyrtodactylus Gray, 1827 from western Arunachal Pradesh, India, Herpetozoa 35, pp. 65-76 : 65

publication ID	https://dx.doi.org/10.3897/herpetozoa.35.e80610
publication LSID	lsid:zoobank.org:pub:4D3E4F4B-5538-46B8-9C44-9F1C21DC6950
persistent identifier	https://treatment.plazi.org/id/121841D4-E95B-40A5-8D0B-9587461F535A
taxon LSID	lsid:zoobank.org:act:121841D4-E95B-40A5-8D0B-9587461F535A
treatment provided by	Herpetozoa by Pensoft
scientific name	Cyrtodactylus kamengensis
status	sp. nov.

Treatment

Cyrtodactylus kamengensis sp. nov.

Figs 2 View Figure 2 , 3 View Figure 3 , 4 View Figure 4 , 5 View Figure 5

Cyrtodactylus khasiensis Agarwal et al. 2010: 89

Cyrtodactylus sp. Agarwal et al. (2014):147

Cyrtodactylus “KM255196” Mirza et al. (2021):21

Holotype.

male, BNHS 3113, Shergaon, West Kameng District, Arunachal Pradesh (27.075528°N, 92.123500°E, elevation 950 m) collected by Mandar Sawant, Pushkar Phansalkar and Harshal Bhosale on 8 August 2021.

Paratypes.

four males BNHS 3114 & BNHS 3115, and NCBS NRC-AA-0020 and NRC-AA-0021, from the same locality as holotype, collected on 8 August 2021.

Etymology.

The specific epithet refers to the Kameng River in western Arunachal Pradesh close to which the new species was discovered.

Diagnosis.

Cyrtodactylus kamengensis sp. nov. can be distinguished from all congeners by its moderate body size (SVL 70.2-78.6 mm, mean 73.84); 9-12 supralabials; 9-10 infralabials; 20-24 bluntly conical, feebly keeled dorsal tubercles; 49-58 paravertebral tubercles; 30-34 ventral scales between distinct ventrolateral folds; no precloacal groves; 7-11 precloacal pores in a continuous series; three to four rows of enlarged scales below pored scales, slightly larger than pored scales, femoral pores absent; 9-13 distal subdigital lamellae on digit IV of pes; subcaudal scalation of original tail without enlarged plates. Dorsum with paired irregular dark brown blotches on a light brown background.

Comparison.

Molecular data for ND2 gene suggest that Cyrtodactylus kamengensis sp. nov. is a member of the ' Cyrtodactylus peguensis ' group ( Grismer et al. 2021) and is here compared with members of this clade. Intraspecific uncorrected pairwise sequence divergence (p -distance) for samples across the two known localities for the species is 0-3% and an interspecific divergence of 19-26% calculated for ND2 gene (Table 2 View Table 2 ). The new species, C. kamengensis sp. nov. differs from members of the ' Cyrtodactylus peguensis ' group as follows: dorsal tubercle in 20-24 rows (vs. 16-18 in C. annandalei Bauer, 24-25 in C. bhupathyi Agarwal, Mahony, Giri, Chaitanya & Bauer, 18 in C. cayuensis Li and C. mandalayensis Mahony, 15-18 in C. pyinyaungensis Grismer, Wood Jr, Thura, Zin, Quah, Murdoch, Grismer, Lin, Kyaw & Lwin, 17-19 in C. peguensis (Boulenger), 15-17 in C. fasciolatum (Blyth), 14-15 in C. markuscombaii (Darevsky, Helfenberger, Orlov & Shah), 13 in C. meersi Grismer, Wood, Quah, Murdoch, M Grismer, Herr, Espinoza, Brown & Lin); ventrolateral folds present (vs. absent in C. annandalei , C. himalayicus (Annandale); weak in C. nyinyikyawi Grismer, Wood, Quah, Murdoch, Grismer, Herr, Espinoza, Brown & Lin and C. pyadalinensis ); 9-12 supralabials (vs. 7-8 in C. annandalei , C. myintkyawthurai Grismer, Wood, Quah, Murdoch, Grismer, Herr, Espinoza, Brown & Lin, C. pyinyaungensis Grismer, Wood Jr, Thura, Zin, Quah, Murdoch, Grismer, Lin, Kyaw & Lwin, C. meersi , C. peguensis ) 7-11 precloacal pores in males, femoral pores absent (femoral as well as precloacal pores present in C. myintkyawthurai , C. bhupathyi , C. pyadalinensis and C. meersi ); 49-58 paravetrebral tubercles (vs. 31 or 32 in C. peguensis , 32 in C. meersi , 28-32 in C. myintkyawthurai and 25-30 in C. pyinyaungensis ). The dorsal colouration that is buff with paired irregular blotches distinguished the new species from Burmese members which bear pale to yellow blotches on the head with well-defined paired or fused blotches on the body. The new species is most similar to C. himalayicus , based on morphology in sharing overlapping numbers of precloacal pores, dorsal tubercle row number, ventral scales across belly and in lacking femoral pores. However, it differs from C. himalayicus as follows: ventrolateral fold present in Cyrtodactylus kamengensis sp. nov. vs. absent in C. himalayicus , 6-8 basal lamellae on digit IV of pes vs. 9 in C. himalayicus . Genetically, the new species is closer to C. bhupathyi and C. gubernatoris , from which it differs as follows: 30-34 ventral scales across belly vs. 37 or 38 in C. bhupathyi , 34-37 in C. gubernatoris ; 53-58 paravertebral tubercles vs. 36-45 paravertebral tubercles in C. gubernatoris ; 7-11 precloacal pores vs. 9 precloacal and 6-9 femoral pores in C. gubernatoris .

Description of holotype male BNHS 3113

(Figs 2 View Figure 2 - 5 View Figure 5 ). The holotype is in a generally good condition, except for minor folds of skin on flank (Fig. 2a View Figure 2 ) and ventral scales, all artefacts of preservation; tail tip removed as tissue sample for molecular analyses; part of the scales on the left lower side of the trunk was damaged during capture (Fig. 2b View Figure 2 ).

Adult male, SVL 78.6 mm. Head moderately long (HL/SVL ratio 0.17) and wide (HW/HL ratio 1.04), dorsoventrally depressed (HH/HW ratio 0.61), distinct from neck; loreal region slightly inflated, interorbital area flat, canthus rostralis not prominent; snout moderately short (SE/HL ratio 0.67), almost twice as long as OD (OD/SE ratio 0.48); scales on forehead, canthus rostralis and snout heterogeneous, those in the interorbital region small, rounded and granular; scales on snout and canthus rostralis slightly larger than those on forehead; scales of interorbital and occipital region heterogeneous, granular, those in occipital region mixed with slightly larger, rounded, conical tubercles (Fig. 3a-c View Figure 3 ), a row of large scale (two to three times larger than scales on the canthus rostralis) border the supralabials. Eye small (OD/ HL ratio 0.33); pupil vertical with crenulated margins; supraciliaries mucronate, decreasing in size towards posterior edge of orbit; ear opening oval, obliquely orientated, large; eye to ear distance slightly more than eye diameter. Rostral wider (2.7 mm) than deep (1.8 mm), partially divided dorsally by weakly developed rostral groove; single large supranasal on either side, separated by two small scales (internasals), which are approximately twice the size of enlarged granular scales on snout; rostral in contact with SL I, nasals, supranasals and an internasal; nostrils semicircular, laterally orientated, posterior half covered by nasal pad, each in broad contact with rostral and also surrounded by supranasal, SL I and three or four postnasals; one scale row separates orbit from supralabials; mental slightly wider (3.5 mm) than long (1.9 mm), triangular, two pairs of well-developed postmentals, inner pair longer (maximum length 2.3 mm) than and separating outer pair (maximum length 1.0 mm), outer pair in contact with the inner postmentals for part of its own length; inner postmentals bordered by mental, IL I, outer postmental and six gular scales; outer postmental bordered by inner postmental, IL I and IL II and four gular scales on either side; supralabials 12/12 (7 to mid-orbit), bordered by a row of large, flat, slightly elongated scales (Fig. 3c View Figure 3 ); infralabials 10/10, IL II to IL VII bordered by one row of chin-shields, largest anteriorly; interorbital scale rows across narrowest point of frontal bone approximately 30 scales. Body moderately slender, relatively short (TRL/SVL ratio 0.46) with distinct ventrolateral folds; dorsal scales heterogeneous, mostly rounded granular, intermixed with irregularly arranged small (2-3 times granule size) circular tubercles, bluntly conical and feebly keeled throughout (Fig. 4a View Figure 4 ), becoming more conical and smaller towards flanks, tubercles extend from frontal region to proximal one third of tail length; tubercles on nape smaller than those of dorsum, largest on flanks; enlarged tubercles on tail completely flat and weakly pointed and keeled; tubercles in approximately 21-22 irregular longitudinal rows at mid-body; 49 paravertebral tubercles; ventral scales much larger than dorsal scales, smooth, cycloid, imbricate to subimbricate, 30 mid-body ventral scale rows; gular scales smaller than ventrals and granular, except a few rows of larger, flat and juxtaposed scales, including a single row of chin-shields bordering mental, postmentals and infralabials (Fig. 3c View Figure 3 ). Eleven pitted precloacal scales in a continuous series; no precloacal groove (Fig. 4b View Figure 4 ). Six enlarged scales between pitted precloacal scales and vent, as large as the largest ventrals and first as well as second row of scales much larger than pitted precloacal scales, the other two rows are slightly smaller. Tail partly regenerated, dorsoventrally depressed, without distinct median furrow, tapering; tail tip removed for molecular analyses. Dorsal scales at base of tail granular, gradually becoming flatter, subimbricate posteriorly, increasing in size on lateral aspect, intermixed with 11-12 slightly enlarged tubercles near base of tail and reducing to two by fourth transverse row of tubercles (Fig. 2 View Figure 2 ); ventral scales larger that dorsal scales, imbricate, median row comprises irregularly enlarged subcaudals in one or two rows; three enlarged postcloacal tubercles at base of tail. Fore- and hind-limbs relatively slender; forearm (FL/SVL ratio 0.15) and crus (CL/SVL ratio 0.18) relatively short; digits relatively short, strongly inflected at each joint, all bearing robust, recurved claws; subdigital lamellae widened beneath basal phalanx; basal lamellae series on digits I-V: 3-4-5-5-4 (right manus) and 3-4-6-7-6 (right pes); distal lamellae series on digits I-V: 7-12-13-13-10 (right manus) and 10-12-11-12-11 (right pes) (Fig. 4c, d View Figure 4 ); interdigital webbing absent on manus, rudimentary between Digits I-V of pes; relative length of digits (measurements in mm in parentheses): IV (6.8) > III (6.4) > V (5.8) > II (4.9) > I (3.3) (right manus) and III (8.8) > IV (8.5) > V (7.9) > II (6.0) > I (3.0) (right pes); palmar and plantar scales smooth, rounded; scales on fore-limb heterogeneous, composed of flat, rounded, smooth sub-imbricate scales, gradually increasing in size on forearm, smaller scales appear granular, no enlarged tubercles, ventral portion covered mostly with smaller and granular scales; scales on hind-limbs heterogeneous, dorsal part of thigh and shank, with larger, conical granular scales, intermixed with scattered, enlarged, slightly conical, weakly-keeled tubercles, which are denser on shank than on thigh, anterior portion of thigh and ventral aspect of hind-limb with enlarged, smooth, imbricate scales, a few rows under thigh are slightly larger than those on abdomen.

Colouration in preservative.

Background in a shade of buff with two rows of dark irregular blotches running from the nape to the flank; each of these blotches are placed fairly at an equal distance from each other. The nape bears a rudimentary bar composed of dark spots which continue into a parallel, irregular stripe along the dorso-lateral aspect of the trunk to its middle where it diffuses into individual spots. The paired blotches on the dorsum merge into alternating dark and light bands on the tail. The limbs bear dark unconnected reticulations. The ventral aspect is off white, lacking the diffusion of the dorso-lateral colouration into the lateral edges of the venter. Colouration in life: the overall colouration is a shade of faded brown with irregular dark reticulations on the head, the body bears a pair of dark brown irregularly-arranged blotches with paler posterior borders forming faded thin, white bars on the trunk and the original portion of the tail bears distinct alternate dark and light bands, while the regenerated part of the tail is ochre with dark mottling. The legs bear dark brown and yellowish-brown mottling on a paler background (Fig. 5 View Figure 5 ).

Variation.

the paratypes match the holotype in most aspects, except for details presented here and in Table 1 View Table 1 : the number of postcloacal spurs and their size is variable in the species, ranging from 3 in most specimens to 4 (NCBS NRC AA-0020); the anterior two postcloacal spurs in the holotype are large, whereas only the first one in BNHS 3114 is large and in NCBS NRC AA-0020, all four are of equal size. The number of enlarged, non-pored scales between the precloacal pores and the vent range from 6-9.

Natural history and distribution notes: all the specimens of the new species were collected from near culverts along roads just after dusk. The species was found in sympatry with Hemidactylus cf. malcolmsmithi and H. platyurus . The species appears to be distributed at Shergaon (elevation ~ 1900 m) and Khellong (elevation ~ 500 m) in West Kameng District of Arunachal Pradesh (Fig. 6 View Figure 6 ). Several individuals were observed on mud escarpments and tree trunks (not collected). The forest type at these localities is described as the East Himalayan moist temperate forest (elevation 1500-2600 m) and the Upper Assam Valley Tropical Wet Evergreen forest (below 800 m) by Champion and Seth (2005).