Hemidactylus raya, Kumar & Srinivasulu & Srinivasulu, 2022

Kumar, Gandla Chethan, Srinivasulu, Aditya & Srinivasulu, Chelmala, 2022, Redescription of Hemidactylus giganteus Stoliczka, 1871 with the description of three new allied species (Squamata: Gekkonidae: Hemidactylus Goldfuss, 1820) from peninsular India, Zootaxa 5115 (3), pp. 301-341 : 316-322

Hemidactylus raya sp. nov. C. Srinivasulu, Kumar & A. Srinivasulu

( Figs. 10–13 ; Table 4 )

Hemidactylus giganteus (vide Bansal & Karanth, 2010)

Holotype. NHMOU. REP. H75.2017 , adult female, near Vithala Temple ruins (15.3416° N, 78.4742° E; 423 m a.s.l.), Hampi, Karnataka, India; collected by Gandla Chethan Kumar & C. Srinivasulu, on 3rd February 2017.

Paratype. NHMOU. REP. H82.2017 , Adult male; collected on 4th February 2017; other details same as holotype .

Additional material. BNHS 1510 , male, Basapur (15.3636° N, 76.4013° E; 468 m a.s.l.), Koppal District , Karnataka, India; collected by Ashok Captain.

Etymology. The specific epithet, singular nominative noun raya is derived from the Kannada word râya , meaning ‘king’ as the species was discovered in Hampi, the capital of the Vijayanagara empire (1336–1646 AD), the kings of which were titled ‘Râya ’.

Suggested Common Name. Deccan giant leaf-toed gecko / Deccan giant rock gecko.

Diagnosis. A large-sized Hemidactylus (SVL averaging 101.10 ± 12.30 mm, n =2; maximum SVL up to 113 mm). Dorsal pholidosis homogenous with more or less uniform, irregularly sized and shaped small granular scales; complete absence of enlarged tubercles on midbody dorsum. First supralabial in contact with nasal, but not in contact with the nostril. Two well-developed pairs of postmentals, inner pair broadly in contact with each other and considerably larger than the outer pair. Ventrolateral folds indistinct, 38–39 scale rows across venter. Enlarged scansors on all digits; 11–12 (manus) and 10–12 (pes) divided scansors beneath first digit, and 13–15 (manus) and 14–16 (pes) beneath the fourth digit. 17 femoral pores on each thigh, separated by seven poreless scales in the male. 15–16 supralabials and 10–12 infralabials. Tail depressed, oval in transverse section without a median dorsal furrow; scales on the tail large and imbricate, slightly larger than dorsals of body; ventral scales of tail large and imbricate, separated with medial row of transversely enlarged and irregularly arranged subcaudal plates.

Comparison with other congeners. Based on the dorsal pholidosis and general appearance, Hemidactylus raya sp. nov. is similar to H. giganteus sensu stricto, but differs from them based on 17 femoral pores in males on each side of the thigh separated by seven poreless scales (versus 18–23 femoral pores on each side with a gap of 7–8 poreless scales in H. giganteus sensu stricto). Dorsal scalation with irregularly sized and shaped granular scales (versus dorsum with small granules, intermixed with 10–12 rows of irregularly arranged, slightly larger, rounded, weakly-keeled tubercles at midbody in H. yajurvedi ; 12–15 rows of irregularly arranged flattened to weekly conical tubercles on the dorsum in H. hemchandrai ), and 17 femoral pores separated by 7 poreless scales in males (versus 10–12 femoral pores on each thigh separated by 5–8 poreless scales in H. yajurvedi , and 10–11 femoral pores on each thigh separated by 5–6 scales in H. hemchandrai ).

Furthermore, this taxon also differs from the other two similar-looking cryptic species described in this paper in having a different combination of number of femoral pores and poreless scales separating them (see Hemidactylus giganteus account above).

The large size (SVL up to 113 mm) of H. raya sp. nov. distinguishes it from many other Indian congeners which are significantly smaller (SVL up to approximately 70 mm): H. albofasciatus , H. aquilonius , H. chikhaldaraensis , H. chipkali , H. flavicaudus , H. flaviviridis , H. frenatus , H. garnotii , H. cf. gleadowi , H. gracilis , H. gujaratensis , H. imbricatus , H. kushmorensis , H. leschenaultii , H. malcolmsmithi , H. murrayi , H. parvimaculatus , H. persicus , H. platyurus , H. reticulatus , H. rishivalleyensis , H. sankariensis , H. robustus , H. sataraensis , H. scabriceps , H. treutleri , H. turcicus , H. varadgirii , H. vijayraghavani , and H. xericolus .

The other large-bodied congeners can be distinguished on the basis of a suite of characters (differing or nonoverlapping characters indicated parenthetically): dorsal pholidosis homogenous, with more or less uniform, irregularly sized and shaped small granular scales, complete absence of dorsal tubercles in H. raya sp. nov. (versus enlarged dorsal tubercles, heterogenous, longitudinal rows of fairly regularly arranged, large, striated subtrihedral tubercles in H. aaronbaueri , H. acanthopholis , H. graniticolus , H. hunae , H. kangerensis , H. kolliensis , H. maculatus , H. paaragowli , H. prashadi , H. sahgali , H. sirumalaiensis , H. siva , H. sushilduttai , H. triedrus , H. vanam , and H. whitakeri ).

Description of holotype (NHMOU.REP.H75.2017). The female holotype is generally in good condition ( Fig. 10 ). The body shape is somewhat dorsoventrally flattened, tail is partially curved in a sigmoid manner, eyes are slightly sunken; all artefacts of preservation. Head short (HL/SVL ratio 0.28), slightly elongate (HW/HL ratio 0.69), not strongly depressed (HH/HL ratio 0.43), relatively broad (HW/BW ratio 0.73), distinct from neck ( Fig. 11A, B ). Loreal region slightly inflated, canthus rostralis not prominent. Snout short (SE/HL ratio 0.42), longer than the eye diameter (SE/OD 2.12). Scales on snout, canthus rostralis, forehead and interorbital region granular, homogeneous; scales on snout, canthus rostralis are twice the size of those on the occipital, frontal and interorbital region ( Fig. 11B ). Eye small (OD/HL ratio 0.20); pupil vertical with crenate margins; superciliaries large, mucronate, pointed, slightly larger at the anterior end of orbit. Ear opening small, subcircular (greatest diameter 2.99 mm); eye to ear distance slightly greater than diameter of eye (EE/OD ratio 1.37). Rostral wider (3.93 mm) than deep (1.49 mm); rostrum deeply notched only near the apex; two enlarged supranasals separated by one smaller intranasal, one postnasal on each side which is slightly smaller than internasal, a single smaller sized postnasal on either side; rostral in contact with nostril; supralabial I not in contact with the nostril. Nostrils large, slightly oval, each surrounded by supranasal, internasal, rostral, supralabial I, and postnasal. Mental enlarged, slightly longer (4.17 mm) than wider (4.06 mm), more or less triangular; two well-developed postmentals, the inner pair shorter (3.13 mm) than mental; outer pair more than half the size of the inner pair, separated from each other by inner pair; right outer postmental divided into two scales. Inner postmentals bordered by mental, infralabial I and II, outer postmental, and two gular scales; outer postmental bordered by inner postmental, infralabial II, and three left and four right gular scales ( Fig. 11C ). Supralabials (to midorbital position) nine (right), nine (left); supralabials (to angle of jaw) 16 (right), 15 (left); infralabials (to angle of jaw) 10 (right), 11 (left).

Body relatively stout, trunk not elongate (TRL/SVL ratio 0.42), with indistinct ventrolateral folds without denticulate scales. Dorsal pholidosis homogenous with more or less uniform, moderately regularly sized and shaped small granular scales ( Fig. 12A ). Ventral scales larger than dorsal, smooth, imbricate, slightly larger on precloacal and femoral region than on chest and abdominal region ( Fig. 10B ); 38 or 39 midbody scale rows across venter; gular region with smaller, granular scales, posterior gular scales slightly larger than the rest ( Fig. 11C ). Scales on the palm and sole smooth, granular, rounded; scales on dorsal aspect of upper arm larger than granules on dorsum and subimbricate, posterior portion of forearm with much smaller, conical and granular scales; anterior portion with much larger, smooth, imbricate scales, continuing on the upper part of the hand. Scales on dorsal part of thigh and shank, similar to those on the dorsum, are granular with enlarged, rounded tubercles, which are larger in size on thigh than on shank; the posterior aspect of the thigh lacks enlarged tubercles, while the anterior aspect has larger, smooth, imbricate scales.

Fore- and hindlimbs relatively stout; forearm short (FL/SVL ratio 0.14); tibia short (CL/SVL ratio 0.17). Digits moderately long, strongly clawed; digits I–IV of manus and pes indistinctly webbed; terminal phalanx of all digits curved, arising angularly from distal portion of expanded lamellar pad, half or more than half as long as associated toepad; scansors beneath each toe in straight transverse series, divided except a distal and three to four basal scansors on digit I and one or two in all digits; scansors from proximal-most at least twice the diameter of palmar scales to distal-most single scansor: 11-14-14-14-14 (left manus) and 12-14-14-13-14 (right manus), and 11-14-14- 14-14 (left pes) and 11-14-14-15-15 (right pes) ( Fig. 11D, E ). Relative length of digits (measurements in parentheses, in mm): IV (7.89)> V (7.87)> III (7.36)> II (7.13)> I (4.91) (right manus), and V (8.95)> IV (8.47)> III (8.07)> II (7.45)> I (5.58) (right pes).

Tail strongly depressed, flat beneath, verticillate; length of tail less than snout-vent length (TL/SVL ratio 0.96). Tail covered above with small uniform scales ( Fig. 11F ); ventral scales larger, imbricate, median row (subcaudal plate) slightly broader, not extending across width of the tail proximally, but distally they extend almost across the width of the tail ( Fig. 11G ). First six subcaudals irregularly arranged, while the rest are in a series.

Colouration in life. Dorsum olive-brown with four lighter irregular wavy bands. The transverse markings are discrete, irregularly shaped and sized, with olive-brown mid-portions bordered by a lighter greyish brown. A paler olive mid-vertebral line is evident at the broadest portion of the body, situated medially between the transverse markings ( Fig. 12A ). The medial portions between the transverse bands, and most of the rest of the dorsum is mottled with olive-black markings. Nape with a small saddle-shaped band, pale greyish in colour. On either side of the nape, mottled grey-green blotches extend from the postorbital region to the first transverse band near the shoulder. Crown with numerous small greyish irregular spots, mostly at the periphery and posteromedial portion of the parietal table. Labial scales and infra-orbital regions are pale grey-brown with white mottling. Limbs olive-brown with grey-green annulations, irregular in size extending up to the digits. Digits with olive greyish bands interspersed by olive-brown. A pale discontinuous transverse band is present on the tail base. Tail similar in colour and pattern to dorsum of the body, interspersed by pale grey bands.

Colouration in preservative. The general colouration of the dorsum is pale brown, and the sides of the trunk are white. The characteristic irregular wavy bands on the dorsum and tail are less prominent after preservation. Bands on the forelimbs and hindlimbs are faded, and appear to be paler. Tail distinctly similar to the body, faded to a light wheatish-beige colour.

Variation. The morphological data and mensural counts of the specimens ( Fig. 13 A-C) collected from the type locality ( Table 4 ) show individual variations. The paratype, a male, is significantly smaller (SVL 88.80 mm versus 113.41 mm) than the holotype, a female, and has 17 femoral pores on both the left and the right sides respectively, separated by seven poreless scales ( Fig. 12B ).

Distribution. Hemidactylus raya sp. nov. is currently known to be restricted to the Tungabhadra river basin of Karnataka, and occurs on the boulders and ruins of Hampi, Bellary District. It might also be present in the neighbouring district of Koppal, as one specimen (BNHS 1510) from Basapur, Koppal District matches morphologically and meristically with this taxon. The taxonomic position of other specimens assigned to H. giganteus sensu lato from Karnataka and Maharashtra ( Smith 1935; Giri et al. 2003; Srinivasulu et al. 2014) needs to be confirmed. Pending taxonomic verification of these populations we propose to provisionally refer to them as Hemidactylus cf. giganteus .

Natural history. Hemidactylus raya sp. nov. is largely a rupicolous leaf-toed gecko. It was encountered on rock boulders ( Fig. 13B, C ), temple ruins, and dilapidated buildings. In most of the localities it was found sharing its habitat with Hemidactylus cf. gleadowi and Hemidactylus flaviviridis .

Figures

FIGURE 10. Hemidactylus raya sp. nov. (holotype, NHMOU.REP.H75.2017, adult female). A) Dorsal view, B) Ventral view. Photo by G. Chethan Kumar. Scale bar = 20 mm.

FIGURE 11. Head of the Hemidactylus raya sp. nov. (holotype, NHMOU.REP.H75.2017, adult female). A) Dorsal view of head, B) Lateral view of head, C) Ventral view of head; D) Ventral view of the right manus; E) Ventral view of the right pes; F) Dorsal view of the tail; and G) Ventral view of the tail. Photo by G. Chethan Kumar. Scale bar = 10 mm.

FIGURE 12. Hemidactylus raya sp. nov. A) Details of dorsal pholidosis of the holotype, NHMOU.REP.H75.2017, adult female, B) Precloacal region of paratype (NHMOU.REP.H82.2017, adult male) showing a series of 17 femoral pores on left and right sides separated medially by seven poreless scales. Photo by G. Chethan Kumar. Scale bar = 10 mm.

FIGURE 13. Photographs of Hemidactylus raya sp. nov. Paratype—A) NHMOU.REP.H82.2017; adult male), and live habitus B) & C) not collected. Photo by G. Chethan Kumar & Chelmala Srinivasulu. Scale bar = 10 mm.