Hemidactylus saxicolus, 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 : 323-328

Hemidactylus saxicolus sp. nov.

( Figs. 14–17 ; Table 5 )

Holotype. NHM. OU. REP. H113-2017 , adult male, Raichur Fort (16.1994° N, 77.3494° E; 462 m a.s.l.), Raichur, Karnataka, India; collected by Gandla Chethan Kumar and Krishna Prasad Kante on 7th February, 2017.

Paratypes. NHM. OU. REP. H28-2017 , adult female, Maliyabad (16.1449° N, 77.3482° E; 458 m a.s.l.), Raichur, Karnataka, India; collected by Chelmala Srinivasulu and Aditya Srinivasulu on 7th February, 2017 . NHM. OU. REP. H114-2017 , adult female, other details as in holotype.

Additional materials. NHM. OU. REP. H115-2015 , adult male, NHM. OU. REP. H116-2015 , adult female, (16.6707° N, 77.8334° E; 431 m a.s.l.), Gaddeguda , Mahbubnagar , Telangana State, India; collection by Gandla Chethan Kumar and Krishna Prasad Kante on 4th October, 2015 .

Etymology. The specific epithet is a nominative adjective meaning rock-dwelling, from the combination of Latin words saxum meaning stone and - colus to inhabit, derived from Latin colere to dwell.

Suggested Common Name. Saxatile leaf-toed gecko or Saxatile rock gecko.

Diagnosis. A large sized Hemidactylus (SVL averaging 108.0± 15.4 mm; n =5; maximum SVL up to 122 mm). Dorsal pholidosis homogenous with more or less uniform, irregularly sized and shaped small granular scales; complete absence of enlarged dorsal tubercles at the midbody. First supralabial is in contact with nasal, but not in contact with 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, 42–44 scale rows across venter. Enlarged scansors on all digits; 11–13 (manus) and 11–13 (pes) divided scansors beneath first digit, and 14–16 (manus) and 16–17 (pes) beneath fourth digit. 26–27 femoral pores on each thigh, separated by nine poreless scales in males. Tail depressed, oval in transverse section without a median dorsal furrow; scales on the tail large and imbricate, separated with medial row of transversely enlarged subcaudal plates; first five subcaudals irregularly arranged, while the rest are in a series.

Comparison with other congeners. Based on the dorsal pholidosis and general appearance, Hemidactylus saxicolus sp. nov. is similar to H. giganteus sensu stricto, H. raya sp. nov. and H. aemulus sp. nov., but differs from them based on 26–27 femoral pores in males on each side of the thigh separated by nine poreless scales (versus 18–23 femoral pores on each side with a gap of seven or eight poreless scales in H. giganteus sensu stricto, 17 femoral pores on each side with a gap of 7 scales in Hemidactylus raya sp. nov., and 22–25 femoral pores on each side with a gap of 9–10 poreless scales in H. aemulus sp. nov.). Dorsal pholidosis 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 26–27 femoral pores separated by 9–10 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 ).

Description of holotype (NHM.OU.REP.H113-2017). The holotype is a well-preserved specimen ( Fig. 14A,B ). The body is 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), elongate (HW/HL ratio 0.77), not strongly depressed (HH/HL ratio 0.50), relatively broader (HW/BW ratio 0.94), broadly distinct from neck ( Fig. 15A ). Canthus rostralis not prominent. Snout short (SE/HL ratio 0.43); longer than the eye diameter (SE/OD ratio 2.66). 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. 15A&B ). Eye small (OD/HL ratio 0.16); pupil vertical with crenate margins; superciliaries large, mucronate, pointed, slightly larger at the anterior end of orbit. Ear opening small, subcircular to more or less oval in shape (greatest diameter 2.64 mm); eye to ear distance slightly greater than diameter of eye (EE/OD ratio 1.78). Rostral wide (4.86 mm) than deep (2.58 mm); rostrum notched only near the apex; two enlarged supranasals separated by one or two smaller intranasals, 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 (5.13 mm) than wider (4.02 mm), more or less triangular; two well-developed postmentals, the inner pair shorter (3.48 mm) and wide (2.99 mm) than mental, and broadly in contact with each other (1.50 mm) behind mental; outer pair more or less of similar size of the inner pair, separated from each other by inner pair. 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. 15C ). Supralabials (to midorbital position) 12 (right), 11 (left); supralabials (to angle of jaw) 15 (right), 14 (left); infralabials (to angle of jaw) 11 (right), 11 (left).

Body relatively stout, trunk not elongate (TRL/SVL ratio 0.37), with indistinct ventrolateral folds without denticulate scales. Dorsal pholidosis homogenous with more or less uniform, moderately regularly sized and shaped small granular scales ( Fig. 16A ). Ventral scales larger than dorsal, smooth, imbricate, slightly larger on precloacal and femoral region than on chest and abdominal region; midbody scale rows across venter 41–42; gular region with smaller, granular scales, posterior gular scales slightly larger than the rest of the scales ( Fig. 14B ). 27 (left) and 26 (right) femoral pores on the thigh, separated by 9 poreless scales ( Fig. 16B ). 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 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 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 two to three 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: 13-15-15-15-14 (left manus) and 13-14-16-16-14 (right manus), and 12-16-16-17-17 (left pes) and 12-15-16-17-17 (right pes) ( Fig. 15D&E ). Relative length of digits (measurements in parentheses, in mm): III (9.97)> IV (9.45)> V (9.38)> II (8.47)> I (7.68) (right manus), and V (12.51)> III (11.03)> II (10.76)> IV (10.49)> I (7.61) (right pes).

Tail regenerated. Strongly depressed, swollen at the base, flat beneath, verticillate. Tail slightly less than snoutvent length (TL/SVL ratio 0.66); original tail covered above with small uniform scales, while the regenerated portion has comparatively larger scales ( Fig. 15F ); ventral scales on the original portion of the tail large, imbricate; in the regenerated portion first nine subcaudal scales irregularly arranged, while the rest are in series ( Fig. 15G ).

Colouration in life. Dorsum brown with four lighter irregular wavy bands. The transverse markings are discrete, irregularly shaped and sized, with grey-brown mid-portions bordered by a darker black-brown. The medial portions between the transverse bands, and most of the rest of the dorsum is mottled with small black-brown markings. Nape with a small band, pale brown in colour. On either side of the nape, grey-brown 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 brown with white mottling. Limbs brown with paler annulations, irregular in size extending up to the digits. Digits with pale greyish-brown bands interspersed by darker 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 dark brown, and the sides of the trunk are paler. Bands on the dorsum, forelimbs, and hindlimbs are slightly faded, and appear to be paler. Tail distinctly similar to the body, with bands still clearly visible.

Variation. The morphological data and mensural counts of the specimens collected from the type locality ( Fig. 17A–C ) and specimens from Gaddeguda, Mahbubnagar District, Telangana State ( Table 5 ) show individual variations. The specimens ranged in size from 86.57 mm to 121.99 mm. The male specimen from Gaddeguda (NHM. OU.REP.H115-2015) has 20 femoral pores as opposed to the normal count, and it could be an aberration. Supralabials range from 12–15 (10–13 below the eye/mid orbital position) and infralabials from 10–13. In the paratypes and the additional materials examined, scales across the belly range from 42–44; and the range of lamellae on digit I of pes was 11–13 and digit IV of pes 16–17.

Distribution. Presently Hemidactylus saxicolus sp. nov. is restricted to the Krishna river basin area of Karnataka and Telangana State, and is known from the boulders of Raichur District in Karnataka and Mahbubnagar District in Telangana State.

Natural history. Hemidactylus saxicolus sp. nov. is largely a rupicolous leaf-toed gecko. It was encountered on rock boulders ( Fig. 17C ), fort ruins, and dilapidated buildings. In most of the localities it was found sharing its habitat with Hemidactylus flaviviridis .

Figures

FIGURE 14. Hemidactylus saxicolus sp. nov. (holotype, NHMOU.REP.H113.2017, adult male). A) Dorsal view, B) Ventral view. Photo by G. Chethan Kumar. Scale bar = 20 mm.

FIGURE 15. Head of the Hemidactylus saxicolus sp. nov. (holotype, NHMOU.REP.H113.2017, adult male). 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 16. Hemidactylus saxicolus sp. nov. (holotype, NHMOU.REP.H113.2017, adult male). A) Details of dorsal pholidosis, B) Precloacal region showing a series of 26 femoral pores on left side and 27 femoral pores on right side separated medially by nine poreless scales. Photo by G. Chethan Kumar. Scale bar = 10 mm.

FIGURE 17. Photographs of Hemidactylus saxicolus sp. nov. Paratypes—A) NHMOU.REP.H114.2017, adult female, B) NH- MOU.REP.H28.2017, adult female, and live habitus C) Holotype, NHM.OU.REP.H113-2017, adult male. Photo by G. Chethan Kumar & Chelmala Srinivasulu.