Dravidogecko meghamalaiensis, Chaitanya & Giri & Deepak & Datta-Roy & Karanth, 2019

Chaitanya, R., Giri, Varad B., Deepak, V., Datta-Roy, Aniruddha & Karanth, Praveen, 2019, Diversification in the mountains: a generic reappraisal of the Western Ghats endemic gecko genus Dravidogecko Smith, 1933 (Squamata: Gekkonidae) with descriptions of six new species, Zootaxa 4688 (1), pp. 1-56 : 21-23

publication ID	https://doi.org/ 10.11646/zootaxa.4688.1.1
publication LSID	lsid:zoobank.org:pub:EB2399FD-6534-49B7-B6BC-56EC001AA0C9
DOI	https://doi.org/10.5281/zenodo.5699735
persistent identifier	https://treatment.plazi.org/id/834402BB-16D9-4D53-A239-312DFCE20612
taxon LSID	lsid:zoobank.org:act:834402BB-16D9-4D53-A239-312DFCE20612
treatment provided by	Plazi
scientific name	Dravidogecko meghamalaiensis
status	sp. nov.

Treatment

Dravidogecko meghamalaiensis sp. nov.

( Figs 8 View FIGURE 8 A–D, 13D, 14B; Table 6 View TABLE 6 )

Hemidactylus anamallensis: Bauer & Russell, 1995 Hemidactylus anamallensis [non Gecko anamallensis Günther, 1875 ]— Chandramouli & Ganesh, 2010;

Holotype. BNHS 2345 View Materials , an adult male, Meghamalai (9.6925 °N, 77.3992 °E; ca. 1480 m asl.), Theni District , Tamil Nadu, collected by RC on 30 th May, 2016. GoogleMaps

Paratypes. Details of collection same as the holotype. BNHS 2346 View Materials , BNHS 2347 View Materials , BNHS 2348 View Materials , BNHS 2349 View Materials , ZSIK 2977 , ZSIK 2979 – adult females; ZSIK 2978 and ZSIK 2980 adult males.

Type locality. Approximately 8 km southwest of Meghamalai village, en route to the Highwavy Mountains in Theni District, Tamil Nadu.

Summarized description and diagnosis. Snout-vent length up to 48.7 mm (n=9); two pairs of well-developed postmentals, inner pair only slightly longer than the outer (2PML/1PML 0.82–0.96), and of comparable length to the mental; ventral scales counted at midbody 28–34; precloacofemoral pores, 36–38 (n=3); subdigital lamellae under digit IV of manus 7–9 and under digit IV of pes, 9 or 10; supralabials, 9–11 and infralabials 8–10 on each side.

Dravidogecko meghamalaiensis sp. nov. can be distinguished from other congeners based on the following characters: number of precloacofemoral pores (PcFP 36–38 versus 45 or 46 in D. anamallensis & 52–56 in D. septentrionalis sp. nov.); inner postmentals comparable in length to mental ( ML /1PML 0.95–1.23 versus much longer, 0.74–0.81 in D. annamallensis ); fewer subdigital lamellae under digit IV of pes (9 or 10 versus 11 or 12 in D. annamallensis ).

Genetic divergence (p-distance). Dravidogecko meghamalaiensis sp. nov. exhibits 0.4% intraspecific variation while it is 13.1% –13.8% divergent from D. anamallensis and 13.0%–13.7% divergent from D. septentrionalis sp. nov. ( Table 9 View TABLE 9 ).

Description of holotype. The holotype is in good condition ( Fig 8A View FIGURE 8 ). The head is slightly tilted towards the right, tail curved towards left and two distinct folds of skin just beneath the forearm insertion—all artefacts of preservation. Body is dorsoventrally flattened with the distal half of tail regenerated. Adult male, SVL 45.1 mm. Head short (HL/SVL 0.28), slightly elongate (HW/HL 0.67), not depressed (HH/HW 0.56), distinct from neck. Loreal region slightly inflated, canthus rostralis indistinct ( Fig 8C View FIGURE 8 ). Snout short (SE/HL 0.39), longer than orbital diameter (OD/SE 0.57); scales on snout, canthus rostralis, inter-orbital region, forehead, occipital and nuchal regions granular and rounded with those on the snout and canthus rostralis being larger ( Fig 8B View FIGURE 8 ). Eye small (OD/HL 0.22); pupil vertical with crenulated margins; supraciliaries small, roughly triangular, pointed upwards and gradually increasing in size anteriorly. Ear opening elliptical (longer diameter 0.8 mm); eye to ear distance longer than diameter of eye (EE/OD 1.37). Rostral wider than deep (RL/RW 0.30), rostral groove distinct but extending only marginally downwards from the suturing with internasals, medially; two large internasals, separated by two smaller, subequal scales, all in broad contact with rostral; two postnasals on either side, slightly smaller than the internasals, the lower in contact with supralabial I; rostral in contact with nasal, supralabial I, internasals and the two smaller scales separating the internasals; nostrils about the size of the lower postnasal, roughly circular with nasal pad visible posteriorly; nasal surrounded by internasal, rostral, two postnasals and a small scale separating it from supralabial I on either side; 2–4 rows of scales separate orbit from supralabials at mid-orbital position. Supralabials roughly rectangular, increasing in length anteriorly. Supralabials (to midorbital position) 6 (right), 7 (left); supralabials (to angle of jaw) 9 (right), 9 (left); infralabials (to angle of jaw) 8 (right), 8 (left). Mental triangular; two pairs of welldeveloped postmentals, the inner pair slightly shorter (0.9 mm) than the mental (1.1 mm), and in strong contact with each other (0.5 mm) behind mental; outer pair similar in size to inner pair, separated from each other by two gular scales that are only smaller than postmentals ( Fig 8D View FIGURE 8 ). Inner postmentals bordered by mental, infralabial I, outer postmentals and two smaller gular scales; outer postmentals bordered by infralabials I (only on the left) and II, inner postmentals, and five smaller gular scales each of dissimilar sizes on either side. Body relatively slender, elongate (TRL/SVL0.49). Dorsal pholidosis homogenous, composed of small, rounded granules, becoming slightly larger, flatter, weakly pointed and sub-imbricate laterally; Ventral scales larger than dorsals, largely homogeneous in shape and size, smooth, flat, sub-imbricate; gular region with smaller, granular, juxtaposed scales; anterior gular scales visibly larger, flatter; scales on femoral region larger than those on sacrum and chest with some precloacal scales being largest; midbody scale rows across belly 28–29. Non-lamellar scales in the palmar and plantar regions heterogeneous in size, rounded and juxtaposed on palm and sole; scales on dorsal aspect of upper arm larger than granules on dorsum, flat, pointed, sub-imbricate and smooth; dorsal aspect of forearm with smaller, sub-imbricate scales intermixed with a few rounded granules around the elbow; scales on dorsal aspect of hand and digits larger than those on forearm, flat, weakly pointed and imbricate; scales on anterior aspect of thigh large, flat, imbricate and weakly pointed; rest of the dorsal scales on hindlimb smaller, granular and rounded. Scales on dorsal aspect of foot larger than those on shank, flat, weakly pointed and imbricate.

Forearm (FL/SVL 0.11) and tibia short (CL/SVL 0.14); digits moderately short with relatively long terminal phalanges, strongly clawed; all digits of manus and digits I–IV of pes indistinctly webbed; terminal phalanx of all digits curved, arising angularly from distal portion of expanded lamellar pad, more than half as long as associated toepad; scansors beneath each toe undivided throughout, in a straight transverse series: 6-6-7-7-7 (left manus), 6- 7-7-7-6 (right manus), 6-7-8-9-7 (left pes), 6-7-8-9-7 (right pes). Relative length of digits (measurements in mm in parentheses): IV (4.1)> III (3.9)> II (3.6)> V (3.5)> I (2.9, claw broken) (left manus); IV (5.0)> III (4.5)> V (4.3)> II (4.1)> I (3.3) (left pes).

Tail long (TL/SVL 1.06), rounded at the base, flat beneath, tapering posteriorly, covered above uniformly with round, smooth, flat, sub-imbricate scales that become slightly larger laterally; subcaudal scales larger, with an undivided median series of enlarged scales that continue until the regenerated portion. An uninterrupted series of 36 precloacofemoral pores that are only faintly visible towards the knee ( Fig 13D View FIGURE 13 ).

Variation in paratypes. Rostral groove extends halfway through the scale in BNHS 2346 View Materials , BNHS 2347 View Materials , BNHS 2348 View Materials , ZSIK 2978 , ZSIK 2979 . Internasals separated by one smaller scale in 2346, BNHS 2347 View Materials , ZSIK 2976 and ZSIK 2979 . Inner postmentals in contact with infralabials I and II in BNHS 2347 View Materials (L) , BNHS 2348 View Materials (L) , ZSIK 2978 (R) and ZSIK 2980 (R) . Inner postmentals bordered posteriorly by three gular scales in BNHS 2346 View Materials , BNHS 2348 View Materials , ZSIK 2978 and ZSIK 2979 and four in ZSIK 2976 and ZSIK 2977 . Outer postmentals bordered by 6 gulars in BNHS 2346 View Materials (L) and ZSIK 2979 (R) and 4 in ZSIK 2976 (L) , ZSIK 2977 (L) and ZSIK 2978 (L,R) . Outer postmentals in contact only with infralabial II in ZSIK 2978 (R) and ZSIK 2980 (R) and only with infralabial I in BNHS 2347 View Materials (L) and BNHS 2348 View Materials . Other morphological variations are listed in Table 6 View TABLE 6 .

Colour in preservative. Dorsum predominantly light brown, mottled with darker, discontinuous streaks from the snout to the base of tail ( Fig 8A View FIGURE 8 ). Similar mottling visible on dorsal aspect of limbs. Neck with a roughly circular, dark blotch flanked by 2 longitudinal streaks on either side. Posterior part of head demarcated by a disctinct horizontal streak. Inter-orbital region slightly darker than rest of the body with scattered vague dark-brown blotches. Labials appear paler than rest of the head with faint spots that are darker. Supralabials bordered by a dark, roughly triangular streak from nostril to eye. Limbs no different from rest of the dorsum. Tail predominantly grey with darker, faint, saddle shaped markings. Venter predominantly cream coloured. Ventral surface of tail pale, with scattered midbrown speckling throughout until the regenerated portion, which is predominantly mid-grey.

Colouration (in life). Dorsum pale with dark-brown streaks throughout that are bordered by one or two rows of yellowish scales ( Fig 14B View FIGURE 14 ). Head dorsum ground colour, posterior part of snout predominantly with scattered yellow scales. Irregularly arranged dark spots in the inter-orbital region and forehead. A dark streak emanates from loreal region up to the eye and continues posteriorly into the lateral aspect of the neck. A discontinuous, roughly W shaped collar followed by a dark spot in the occipital region. Six dark, transverse streaks across the vertebral region until the sacrum. Limbs of ground colour with irregular dark streaks. Tail lighter than dorsum, with seven irregular, dark streaks. Tip of tail regenerated.

Etymology. The specific epithet is an adjectival toponym referring to the Meghamalai Hills, where the type series was collected.

Suggested Common name. Meghamalai Dravidogecko .

Distribution. Dravidogecko meghamalaiensis sp. nov. is presently restricted in distribution to the Meghamalai Hills in the southern Western Ghats. Similar habitats are seen in the Vellimalai Range within the Meghamalai Wildlife Sanctuary and in many parts of the Srivilliputtur Grizzled Squirrel Wildlife Sanctuary, where this species could also possibly occur.

Habitat and natural history. The type-series of Dravidogecko meghamalaiensis sp. nov. was collected en route to the Highwavy Mountains within the Meghamalai Wildlife Sanctuary, where the habitat chiefly constitutes moist mixed deciduous forests ( Bhupathy & Babu 2013). Individuals were found on trees and abundantly in unoccupied buildings. Sub-adults (SVL <42 mm) were encountered during the month of June, and larger individuals during November. These habitats are at an altitude of 1300–1600 m asl and receive an average annual rainfall of 1500 mm ( Bhupathy et al. 2009).