Cyrtodactylus jaintiaensis, Agarwal & Mahony & Giri & Chaitanya & Bauer, 2018

Agarwal, Ishan, Mahony, Stephen, Giri, Varad B., Chaitanya, R. & Bauer, Aaron M., 2018, Six new Cyrtodactylus (Squamata: Gekkonidae) from northeast India, Zootaxa 4524 (5), pp. 501-535 : 520-524

Cyrtodactylus jaintiaensis sp. nov.

Figs. 9 and 12–14 .

Holotype. Adult female ( BNHS 2248 , field number CES09/1228), collected from the vicinity of Tyrshi Falls near Jowai town , West Jaintia Hills district , Meghalaya state, India (25.46956°N, 92.18313°E, 1350 m asl.) by Tarun Khichi , Aniruddha Datta-Roy and Ishan Agarwal on 15 November 2010.

Paratypes. Adult males ( BNHS 2246 & BNHS 2247 ), bear the same collection data as holotype .

Etymology. The specific epithet is a toponym named after the type locality of the new species in the Jaintia Hills, West Jaintia Hills district, Meghalaya.

Diagnosis. Cyrtodactylus jaintiaensis sp. nov. can be distinguished from all congeners by its large body size (SVL to at least 96.2 mm); eight or nine supralabials; nine or 10 infralabials; 19 or 20 longitudinal rows of rounded, conical, feebly keeled dorsal tubercles; tubercles extending to third tail segment; 30–34 paravertebral tubercles; 40–42 ventral scales between ventrolateral folds; no precloacal groove; 11 or 12 precloacal pores on males and females, no femoral pores; a row of enlarged scales posterior to precloacal pore-bearing scales, slightly larger than pore-bearing scales; 15–18 total subdigital lamellae beneath toe IV of pes; subcaudal scalation of original tail without enlarged subcaudals; dorsal pattern of indistinct light and dark blotches; tail with alternating dark and lighter bands.

Description of holotype. Holotype in good preservation condition: tail tip removed for tissue voucher, constriction just anterior to hind limb insertion due to overzealous tag tying. Adult female, SVL 96.2 mm. Head long (HL/SVL 0.26), slightly wide (HW/HL 0.69), somewhat depressed (HD/HW 0.57), distinct from neck; loreal region somewhat inflated, interorbital region flat, canthus rostralis not prominent; snout short (SE/HL 0.42), twice as long as orbital diameter (ED/SE 0.54); scales on snout and canthus rostralis granular, juxtaposed, homogenous in shape with scales on snout larger; scales on interorbital region, forehead and occipital region smaller, granular, juxtaposed; forehead and occipital region interspersed with larger tubercles that are rounded, smooth and twice the size of adjacent granules, enlarged tubercles sparse on forehead, denser on occipital region. Eye small (ED/HL 0.23); pupil vertical with crenulated margins; supraciliaries similar in size and shape to adjacent granules, weakly pointed; dorsal surface of eyelids covered with small granular scales, row of enlarged tubercles bordering supraciliaries absent. Ear opening oval, obliquely oriented, large; eye to ear distance larger than diameter of eye (ED/EE 0.71). Rostral wider (3.6 mm) than deep (2.0 mm), partially divided dorsally by a weakly developed rostral groove; single much enlarged, rounded supranasals on either side, in contact with each other; rostral in contact with supralabial I, nostrils and supranasals; nostrils oval, laterally oriented, posterior half covered by an indistinct nasal pad, each in broad contact with rostral and surrounded by supranasal, supralabial I, and five smaller, granular postnasal scales; five rows of granular scales between mid-orbit and supralabials; mental wider (2.8 mm) than deep (2.2 mm), two well-developed postmentals on either side, inner pair in broad contact (1.6 mm) with each other behind mental, twice size (2.3 mm) of and separating outer pair (1.1 mm); each inner postmental bordered by mental, infralabial I, outer postmental and three gular scales; outer postmentals bordered by inner postmental, infralabials I and II, a large, roughly hexagonal scale posteriorly and three or four slightly enlarged gular scales; seven supralabials on each side at midorbital position; supralabials to angle of jaw, eight on right side and nine on left side, bordered by a row of flat, somewhat elongated scales slightly larger than their adjacent granules; infralabials, 10 on left side, infralabials II–VI bordered by two rows of enlarged scales, anteriormost largest.

Body slender (BW/TRL 0.42), short (TRL/SVL 0.48); dorsal scales heterogeneous, mostly rounded granules, intermixed with irregularly arranged, enlarged tubercles, tubercles rounded, feebly keeled, flatter and more keeled towards vertebral region, more pointed toward flanks; indistinct ventrolateral fold on either side covered by a single row of enlarged smooth scales interspersed with much smaller granules; tubercles extend from occipital region to anterior half of remaining portion of tail; tubercles on nape smaller than those of dorsum; 20 dorsal tubercles across mid-dorsum; 34 paravertebral tubercles; ventral scales much larger than dorsals, smooth, cycloid, subimbricate; slightly smaller under thighs; two rows of enlarged subimbricate scales along posterior border of precloacal pores; 40 ventral scales between ventrolateral folds; gular region with much smaller granular scales throughout, except two rows which are twice as large, flat and juxtaposed, and run from posterior margin of outer postmentals, bordering infralabials; 12 minute precloacal pores in a continuous series; femoral pores absent; no precloacal groove.

Fore and hind limbs slender; forearm (FL/SVL 0.14) and tibia (CL/SVL 0.16) short; digits short, strongly inflected at each joint, all bearing robust recurved claws that are slightly longer than their claw sheath; five subdigital lamellae in basal series and 11 in distal series (digit IV, right manus); seven basal and 10 distal lamellae with three non-lamellar granules at inflection (digit IV, right pes); slight inter-digital webbing between toes I–IV, absent between fingers; relative length of digits: I <II <V <III <IV (right manus) and I <II <V <III <IV (right pes); scales on the palms and soles smooth, flat, juxtaposed, with those on soles being slightly larger; scales on fore limbs heterogeneous, comprising rounded, granular, juxtaposed scales becoming larger, flat, smooth and subimbricate anteriorly; granules of forearms sparsely interspersed with slightly enlarged rounded tubercles; ventral surfaces covered mostly with flat, granular, juxtaposed scales; scales on hind limbs heterogeneous, dorsal part of thighs and shanks with small slightly pointed granular scales, intermixed with scattered, rounded, enlarged, feebly keeled tubercles; ventral aspect of hind limbs with much enlarged, smooth, subimbricate scales.

Tail tip absent, two thirds original, somewhat rounded, slender, tapering, divided into indistinct segments; seven rows of enlarged, rounded, feebly keeled tubercles scattered on tail base; four to six rounded, flattened tubercles at end of first to third segments; remaining dorsal caudal scales smooth, rounded, subimbricate, similar in size dorsally getting larger on lateral aspect; subcaudal scales larger, smooth, imbricate; no distinct median series; three enlarged smooth post cloacal spurs on each side.

Colouration in life (for paratype, BNHS 2246, Fig 12 ). Dorsal ground colour of head, body, limbs and tail grey-brown, strongly mottled with tan, yellow and white; top of head strongly mottled toward occiput; labials lighter than head dorsum and with some yellow streaks; a light yellow narrow postorbital streak that does not extend as far as ear opening; neck and back with black light grey spots forming a reticulate pattern of thick markings, numerous light and dark brown tubercles on dorsum; limbs with light tan spots; ten dark and nine light caudal bands on complete original tail, dark bands more than four times as wide as light bands; rest of ventral surfaces immaculate; iris green-grey with dark reticulations, pupil bordered by orange-red.

Colouration in preservative ( Figs. 13 & 14 ). Dorsal ground colour of head, body, limbs and tail light-brown; top of head strongly mottled with fine dark markings; labials similar to top of head bearing scattered darker spots; a light narrow postorbital streak does not extend to ear opening; nape and dorsum bear black and light-grey spots, numerous light and dark brown tubercles on dorsum; limbs with slightly darker reticulate markings; four dark and three light bands on original portion of tail, darker bands wider than light, regenerated portion colouration and markings similar to limbs; rest of ventral surfaces dirty white.

Variation. The two adult male paratypes have 11 or 12 distinct precloacal pores and a distinct hemipenal bulge, and are similar in colour pattern to the holotype except there are approximately eight dark and nine light caudal bands on BNHS 2247, and ten dark and nine light caudal bands on BNHS 2246. Variation in scale counts and morphometrics is summarized in Table 4.

Distribution and Natural History. The species is only known from the vicinity of Tyrshi Falls, in the Jaintia Hills. The geckos were spotted at night by eye-shine on vertical rock faces. The landscape is made up of patches of forest in an agricultural matrix.

Comparisons. Cyrtodactylus jaintiaensis sp. nov. is a member of the mountain clade and is the poorly supported sister lineage to C. montanus sp. nov. and C. sp. Mizoram, and is separated from members of the clade by pairwise uncorrected genetic distance of approximately 18.7–21.4%. Cyrtodactylus jaintiaensis sp. nov. can be diagnosed by its large body size (SVL up to 96 mm), and the presence of 11 or 12 precloacal pores in a single series in males from C. chrysopylos (SVL up to 79 mm, enlarged pore-bearing post-precloacal scales in males), and C. gansi (SVL up to 63 mm, 16–29 PcFP). Cyrtodactylus jaintiaensis sp. nov. can be diagnosed by its reticulate dorsal pattern from C. brevidactylus (3–dark dorsal blotches between nape and sacrum). The differentiation of C. jaintiaensis sp. nov. from C. montanus sp. nov., and C. nagalandensis sp. nov. is detailed following their descriptions. Major diagnostic characters for the new species and regional congeners are summarized in Table 3.

Figures

FIGURE 9. Paratypes of the new species described in this paper. From left to right, top panel: Cyrtodactylus kazirangaensis sp. nov. (BNHS 2147, 2149), Cyrtodactylus jaintiaensis sp. nov. (BNHS 2246), Cyrtodactylus montanus sp. nov. (BNHS 2234), and Cyrtodactylus jaintiaensis sp. nov. (BNHS 2247); bottom panel: Cyrtodactylus nagalandensis sp. nov. (BNHS 2254), Cyrtodactylus septentrionalis sp. nov. (BNHS 1989), and Cyrtodactylus montanus sp. nov. (BNHS 2231–2233).

FIGURE 12. Cyrtodactylus jaintiaensis sp. nov. in life (adult male paratype, BNHS 2246).

FIGURE 13. Dorsal view (A), ventral view (B), and details of dorsal pholidosis (C) of adult female holotype (BNHS 2248) of Cyrtodactylus jaintiaensis sp. nov. Scale bars 10 mm.

FIGURE 14. Head of Cyrtodactylus jaintiaensis sp. nov. (adult female holotype, BNHS 2248), dorsal (A), lateral (B), and ventral (C) view. Scale bars 10 mm.