Cnemaspis agarwali, Khandekar, 2019

Khandekar, Akshay, 2019, A new species of rock-dwelling Cnemaspis Strauch, 1887 (Squamata: Gekkonidae) from Tamil Nadu, southern India, Zootaxa 4571 (3), pp. 383-397 : 386-392

Cnemaspis agarwali sp. nov.

( Figs. 2–7 ; Table 1)

Holotype. NCBS-AU486 , adult male, from near Kidayur road (11.500° N 77.859° E; datum WGS84; ca. 350 m asl), Sankari, Salem district , Tamil Nadu state, India, collected by A. Khandekar, C. Daniel, I. Agarwal and R. Chaitanya on 12 November 2017.

Paratypes. NCBS-AU487 , BNHS 2337 , adult males, NCBS-AU485 , BNHS 2336 , adult females, same collection data as holotype . NCBS-AU488 , NCBS-AU490 , and BNHS 2338 , adult males, BNHS 2339 , adult female, same data as holotype except collected by A. Khandekar, I. Agarwal and N. Gaitonde on 19 April 2018 .

Etymology. The specific epithet is a patronym, honouring Ishan Agarwal for his contributions to Indian lizard taxonomy and biogeography, and constant support and encouragement to the author.

Suggested Common Name. Agarwal’s dwarf gecko

Diagnosis and comparison with Indian congeners: A small-sized Cnemaspis , snout to vent length less than 33 mm. Dorsal pholidosis heterogeneous, weakly keeled granular scales intermixed with large strongly keeled, conical tubercles, 9–11 rows of dorsal tubercles, 12–17 tubercles in paravertebral rows; spine-like scales absent on flank. Ventral scales on belly smooth, subimbricate, 24–26 scales across the belly, 102–117 longitudinal scales between mental to anterior border of cloaca. Two pairs of postmentals, inner postmentals strongly in contact with each other, outer postmentals separated by two enlarged chin scales. Subdigital scansors smooth, entire, unnotched; lamellae under digit IV of pes 17–20. Males with 4–6 femoral pores on each thigh, separated on either side by eight poreless scales from four precloacal pores; precloacal pores separated medially by a single poreless scale.. Tail with enlarged, strongly keeled, conical tubercles forming whorls; a median row of sub-caudals smooth, enlarged. Dorsum with 5–7 light grey vertebral blotches between neck and tail base; two single dorsal ocelli on occiput and between forelimb insertions, two pairs on either side just anterior and posterior to forelimb insertions; throat offwhite, strongly suffused yellow on lateral margins with three black longitudinal streaks running parallel to each other; original tail in males with alternating black and whitish-grey bands, regenerated tail orange.

Cnemaspis agarwali sp. nov. can be distinguished from all other Indian congeners on the basis of the following differing or non-overlapping characters: spine-like scales absent on flank (versus spine-like scales present on flank in C. amboliensis , C. assamensis , C. flaviventralis , C. goaensis , C. indraneildasii , C. jerdonii , C. littoralis , C. monticola , and C. nilagirica ); scales on dorsal aspect of trunk heterogeneous (versus scales on dorsal aspect of trunk homogeneous in C. adii , C. assamensis , C. australis , C. boiei (Gray) , C. indica , C. indraneildasii , C. jerdonii , C. kolhapurensis , C. littoralis , C. nilagirica and C. sisparensis ); tail with median row of sub-caudal scales smooth and enlarged (versus median row of sub-caudal scales smooth and not enlarged in, C. ajijae Sayyed, Pyron & Dileepkumar , C. flaviventralis , C. girii , C. limayei ; C. monticola , C. australis with keeled sub-caudal); absence of keeled scales on the venter or gular regions (versus keeled scales on the venter or gular region in C. beddomei and C. goaensis ); males with 4–6 femoral pores on each thigh, separated on either side by eight poreless scales from four precloacal pores; precloacal pores separated medially by a single poreless scale (versus precloacal pores absent, femoral pores present in C. ajijae , C. anaikattiensis , C. flaviventralis , C. girii , C. indica , C. jerdonii , C. kottiyoorensis , C. limayei , C. littoralis , C. mahabali , C. sisparensis , C. heteropholis , C. wynadensis ; only precloacal pores present in C. anamudiensis , C. beddomei , C. maculicollis , C. nairi , C. ornata ; both femoral and precloacal pores absent in C. boiei , C. assamensis ; three femoral and four precloacal pores present in C. otai ; two femoral and two precloacal pores in C. adii ; four to five femoral and three precloacal pores in C. australis ; two to four femoral and three precloacal pores in C. goaensis ; 3–6 femoral pores on each thigh, separated on either side by 7–10 poreless scales from two precloacal pores; precloacal pores separated medially by two or three poreless scale in C. gracilis ; two femoral and two precloacal pores in C. mysoriensis ; three femoral and two precloacal pores in C. yercaudensis ; a continuous series of 26–28 precloacal-femoral pores in C. kolhapurensis ).

Cnemaspis agarwali sp. nov. closely resembles C. gracilis in snout-vent length, dorsal pholidosis, mental and postmental arrangement, ventral scales in longitudinal series, and presence of femoral and precloacal pores. However, it can be distinguished from it by lacking enlarged, conical tubercles on lower flank (versus one or two rows of enlarged, conical tubercles present on lower flank); four precloacal pores separated medially by a single poreless scale (versus two precloacal pores separated medially by two or three poreless scales); by having 12–17 tubercles in paravertebral rows (versus 9–12 tubercles in paravertebral rows in C. gracilis ); by having 9–11 rows of dorsal tubercles (versus 11–14 rows of dorsal tubercles in C. gracilis ); lamellae under digit IV of pes 17–20 (versus lamellae under digit IV of pes 22); presence of two single dorsal ocelli on occiput and between forelimb insertions, two pairs on either side just anterior and posterior to forelimb insertions (versus presence of two single dorsal ocelli on occiput and between forelimb insertions in C. gracilis ).

Description of the holotype. Adult male is in good state of preservation except the head is slightly bent to the right and a dorsolateral fold of skin runs from behind the eye to the groin on the right side; artefacts of preservation ( Fig. 2 A ). SVL 29.8 mm, head short (HL/SVL ratio 0.25), wide (HW/HL ratio 0.73), not strongly depressed (HD/ HL ratio 0.46), distinct from neck. Loreal region slightly inflated, canthus rostralis not prominent. Snout elongate (ES/HL ratio 0.52), longer than eye diameter (ED/ES ratio 0.41); scales on snout and canthus rostralis large, weakly keeled, juxtaposed; larger than those on forehead and interorbital region; occipital and temporal region with much smaller granular scales, intermixed with slightly larger, roughly rounded, tubercles ( Fig. 3 A ). Eye small (ED/HL ratio 0.21); with round pupil; orbit with extra-brillar fringe with small scales that are largest anteriorly; supraciliaries not elongate. Ear opening deep, vertical, small (EL/HL ratio 0.06); eye to ear distance greater than diameter of eye (EE/ED ratio 1.68) ( Fig. 3 C, D ). Rostral much wider (1.4 mm) than long (0.6 mm), incompletely divided dorsally by a strongly developed rostral groove for more than half of its length; single enlarged supranasal, slightly larger than postnasals, separated from one another by much smaller single internasal and two smaller scales on the snout; rostral in contact with supralabial I, nasal, supranasal, internasal and scales separating internasals; nostrils oval, each surrounded by postnasal, supranasal, rostral and supralabial I; two rows of scales separate the orbit from the supralabials ( Fig. 3 A ). Mental enlarged, subtriangular, marginally wider (1.4 mm) than long (1.3 mm); two pairs of postmentals, inner pair large, roughly rectangular, bordered by mental, infralabial I, outer postmentals and two enlarged chin shields; outer postmentals slightly smaller than inner postmentals, bordered by infralabials I, II, inner postmentals and four enlarged chin shields; two enlarged gular scale prevents contact of left and right outer postmentals; chin shields bordering postmentals flat, smooth, slightly smaller than outermost postmentals, rest granular, much smaller, smooth. Infralabials bordered below by a row of slightly enlarged scales, decreasing in size posteriorly ( Fig. 3 B ). Supralabials counted upto angle of jaw seven (L)—six (R), and six at midorbital position on both sides; supralabial I largest, decreasing in size posteriorly; seven infralabials upto angle of jaw on both sides, and five (L)—six (R) at midorbital position; infralabial I largest, decreasing in size posteriorly ( Fig. 3 C, D ). Extra-brillar fringe scales 10–11 on each side, interorbital scale rows across narrowest point of frontal bone nine or ten; 22 scale rows between left and right supraciliaries at midorbit ( Fig. 3 A ).

Body relatively slender, not elongate (AGL/SVL ratio 0.41) without ventrolateral folds or spine-like scales on flanks. Dorsal scales on trunk heterogeneous, weakly keeled granular scales intermixed with much larger strongly keeled, conical tubercles. Tubercles in approximately 11 longitudinal rows at mid-body; 14 tubercles in paravertebral row from occiput to dorsal side of anterior margin of cloaca. Scales on nape slightly smaller than granular scales on dorsum, smaller still on occiput ( Fig. 2 A ) Ventral scales slightly larger than dorsal; those on belly smooth, subimbricate, slightly rounded, subequal from chest to vent; midbody scale rows across belly 25; 105 scales between mental to anterior border of cloaca; scales on throat and pectoral region more elongate than those on belly, flat and imbricate; gular region with slightly smaller granules with those on chin bordering postmentals, enlarged, juxtaposed and flattened ( Fig. 2 B ). Four femoral pores on right thigh and five on left, separated on either side by eight poreless scales from four precloacal pores; precloacal pores separated medially by a single poreless scale ( Fig. 5 C ).

Scales on palm and sole, smooth, flat and roughly rounded; scales on dorsal aspect of manus and pes heterogenous, upper arm with scales slightly larger than those on dorsum, weakly keeled, subimbricate; those near forearm insertion, much smaller, granular; dorsal aspect of forearm with scales smaller than those on upperarm, weakly keeled, flat, roughly rounded; scales on elbow weakly keeled, subimbricate and similar in size to those on upper arm; dorsal aspect of hand predominantly bearing small, flattend weakly keeled, imbricate scales. Ventral aspect of upper arm with smooth, roughly rounded, weakly conical granules; scales on fore arm and wrist with larger, smooth, weakly imbricate scales. Scales on dorsal aspect of thigh larger than those on dorsum, weakly keeled, imbricate except those near hindlimb insertion which are much smaller, roughly rounded, conical granules. Scales on dorsal aspect of knee and shank slightly smaller than those on dorsum of thigh, subimbricate, weakly keeled; dorsal aspect of foot predominantly bearing small, flattend, weakly keeled, imbricate scales; scales on ventral aspect of thigh similar to those on midbody ventrals; those on ventral surface of shank larger than those on thigh, smooth, imbricate ( Fig. 2 A, B ). Fore and hind limbs moderately long, slender (FL/SVL ratio 0.16); (CL/ SVL ratio 0.20); digits long, with a strong, recurved claw, distinctly inflected, distal portions laterally compressed conspicuously. Series of unpaired lamellae on basal portion of digits, separated from narrower distal lamellae by a single large scale at the inflection; proximal lamellae series: 2–3–3–3–3 (right manus; Fig. 5 A ), 2–3–5–5–4 (right pes; Fig. 5 B ), 1–3–3–3–3 (left manus), 1–3–5–5–5 (left pes)); distal lamellae series: 8–10–11–11–10 (right manus; Fig. 5 A ), 8–10–12–12–12 (right pes; Fig. 5 B ), 8–10–11–11–14 (left manus), 8–9–12–13–13 (left pes)). Relative length of digits (measurements in mm in parentheses): IV (2.55)> III (2.52)> V (2.30)> II (2.15)> I (1.55) (left manus); IV (3.40)> V (3.15)> III (2.97)> II (2.71)> I (1.41) (left pes).

Tail not entire, more than half of its length original, short, cylindrical, relatively slender, total length including regenerated portion 16.0 mm ( Fig. 2 A ). Dorsal scales at the base of tail granular, similar in size and shape to granular scales on midbody dorsum, gradually becoming larger, flatter, subimbricate posteriorly, intermixed with slightly enlarged, strongly keeled, conical tubercles forming whorls; four to six tubercles on first two to five whorls. Regenerated portion of tail covered above with scales similar to those on original tail, without enlarged tubercles forming whorls ( Fig. 2 A ). Scales on ventral aspect of original tail much larger than those on dorsal, imbricate, smooth, with a series of three enlarged subcaudal scales of which the median series is almost twice the size of adjunct two rows, roughly hexagonal; those on tail base much small, imbricate and smooth. Regenerated portion of tail covered below with much larger, smooth, roughly rectangular scales, a single enlarged postcloacal spur on each side ( Fig. 5 D ).

Colouration in life (based on paratype NCBS-AU490, Fig. 7 A ) Dorsal ground colour of head, body and limbs and tail base light orange. Snout, canthus rostralis light yellow and orange; occiput with light orange blotch mixed with few light enlarged tubercles; two single dorsal ocelli on occiput and between forelimb insertions, two pairs of ocelli on either side just anterior and posterior to forelimb insertions; labials light yellow, four or five indistinct light

grey cross-bars; supraciliary scales in front of eye bright yellow, those above eye light yellow and each scale dotted with brown; seven pairs of orange paravertebral blotches partially fused middorsally to form five indistinct mid dorsal pale yellowish vertebral blotches; limbs with four or five light orange bands, irregularly spotted with few light brown tubercles; original tail ash-grey with darker tubercles forming nine indistinct bands from tail base to regenerated portion, which is dark orange. Belly, underside of limbs light yellow with few black dotted scales scattered irregularly; gular region with two longitudinal brown streaks on either side running from angle of jaw up to the anterior margin of neck; tail ventrum ashy white with brown markings, regenerated portion dark orange. Pupil black, iris golden.

Colouration in preservative (based on holotype NCBS-AU486, Fig. 2 ) Colours overall faded to light brown, with orange almost completely lost except on regenerated portion of tail. Labials dotted with light brown, single black streak starting from behind the eye till neck on either side. Two single dorsal ocelli on occiput and between forelimb insertions, two pairs of ocelli on either side just anterior and posterior to forelimb insertions; six indistinct

lighter mid-vertebral blotches of variable size and shape on back and tail base. Ventral side light yellow, throat with two longitudinal streaks of dark brown on either side running from angle of jaw up to the anterior margin of neck.

Variation and additional information from type series. Mensural data for the type series is given in Table 1. There are six male and three female specimens ranging in size from 28.9 mm to 33.0 mm. All paratypes resemble the holotype except as follows: the number of lamellae on digit I of the manus ranges from 9–12 and on digit IV from 13–17, on digit IV of the pes 17–20. NCBS-AU487 has six supralabials on left and five on right and NCBS- AU490 has nine supralabials on left and seven on right side. Ventral scale counts vary from 102 in NCBS-AU487 to 117 in BNHS 2338 ; the number of femoral pores ranges from five or six. Holotype, NCBS-AU486 and five paratypes—NCBS-AU485, NCBS-AU487 , NCBS-AU486 , BNHS 2336 , and BNHS 2337 with incomplete tail; two male paratypes, NCBS-AU490 , BNHS 2338 , and a female paratype, BNHS 2339 with complete tail, slightly longer than body (TL/ SVL ratio 1.26, 1.39, and 1.27 respectively). Five males NCBS-AU487 , NCBS-AU488 , NCBS-AU490 , BNHS 2337 , and BNHS 2338 match the holotype in overall colouration, three female specimens BNHS 2336 , NCBS-AU485 and BNHS 2339 are duller in appearance, tail light brown with indistinct black bands, lacking ashy-grey colouration on tail.

Distribution and Natural history. Cnemaspis agarwali sp. nov. is so far known only from the type locality, at an elevation of ca. 350 m asl. The species was encountered during a single day of fieldwork on an isolated rocky hillock in mid-November near Kidayur road, Sankari. These scansorial, diurnal geckos were observed only on large rocky boulders. On a subsequent visit to the same locality in mid-April, they were abundant and active in the evening, only on the rocky boulders. Soon after dark, they became inactive and were observed predominantly on the ground, in dry leaf litter around the rocky boulders. A few individuals took refuge at base of the rocks and inside the muddy crevices with their heads pointed towards opening of the crevice. Sympatric lizards at the type locality include Hemidactylus frenatus Duméril & Bibron , Hemidactylus graniticolus Agarwal, Giri & Bauer , Hemidactylus parvimaculatus Deraniyagala , Hemidactylus sp., Eutropis bibronii (Gray) , Psammophilus dorsalis (Gray) and Calotes versicolor (Daudin) .

Figures

FIGURE 2. Dorsal view (A) and ventral view (B) of Cnemaspis agarwali sp. nov. (holotype, NCBS-AU486). Scale bars 10 mm.

FIGURE 3. Head of Cnemaspis agarwali sp. nov. (holotype, NCBS-AU486), dorsal (A), ventral (B), right side lateral (C), and left side lateral (D) view. Scale bars 5 mm.

FIGURE 4. Details of dorsal pholidosis at midbody (A) and details of ventral scales at midbody (B) of Cnemaspis agarwali sp. nov. (holotype, NCBS-AU486). Scale bars 5 mm.

FIGURE 5. Ventral view of right manus (A), and ventral view of right pes (B), precloacal and femoral region (C) and ventral view of tail showing smooth, enlarged median subcaudal scale row on original portion of tail of Cnemaspis agarwali sp. nov. (holotype, NCBS-AU486). Scale bars 5 mm.

FIGURE 6. Type series of Cnemaspis agarwali sp. nov. (from left to right, BNHS 2336, NCBS-AU485, NCBS-AU487, BNHS 2337, NCBS-AU488, NCBS-AU490, BNHS 2338 and BNHS 2339). Scale bar 10 mm.

FIGURE 7. Cnemaspis agarwali sp. nov. in life, male (paratype, NCBS-AU490) (A) and female (paratype, BNHS 2339) (B).