Cnemaspis sathuragiriensis, Khandekar & Thackeray & Agarwal, 2024

Khandekar, Akshay, Thackeray, Tejas & Agarwal, Ishan, 2024, Two new species of the Cnemaspis galaxia complex (Squamata, Gekkonidae) from the eastern slopes of the southern Western Ghats, ZooKeys 1196, pp. 209-242 : 209

Cnemaspis sathuragiriensis sp. nov.

Figs 8 , 9 , 10 , 11 , 12

Type material examined.

Holotype. NRC-AA-8349 (AK-R 1510), adult male, from near Sathuragiri entry point (9.7093°N, 77.6307°E; ca 250 m a.s.l.), Sathuragiri, Virudhunagar district, Tamil Nadu state, India; collected by Akshay Khandekar, Ishan Agarwal, Swapnil Pawar and team on 26 April 2022. Paratypes. NRC-AA-8350 (AK-R 1511), NRC-AA-8351 (AK-R 1512), adult males, same data as holotype; NRC-AA-8352 (AK-R 1513), adult male, NRC-AA-8353 (AK-R 1515), subadult female, from near Vazhukkuparai Saptur Reserve Forest (9.7174°N, 77.6244°E; ca 400 m a.s.l.), Sathuragiri; same data as holotype.

Diagnosis.

A small-sized Cnemaspis , snout to vent length ≤ 33 mm (n = 5). Dorsal pholidosis heterogeneous; smooth to weakly keeled granular scales intermixed with irregularly arranged rows of enlarged, weakly keeled, conical tubercles; 6-8 rows of dorsal tubercles at midbody, paravertebral tubercles either absent or irregular; ventral scales subequal from chest to vent, smooth, subcircular and subimbricate with rounded end; 28-30 midventral scales across belly, 130-137 longitudinal ventral scales from mental to cloaca; subdigital scansors smooth, unnotched, some divided and others entire, a distinct enlarged metacarpal scale below digit I; 11-13 lamellae under digit I of manus and 11 or 12 under digit I of pes, 18-21 lamellae under digit IV of manus and 23 or 24 lamellae under digit IV of pes; males with continuous series of seven or eight precloacal pores (n = 4); scales on non-regenerated tail dorsum heterogeneous; small, smooth, subcircular, flattened, subimbricate scales intermixed on anterior one third portion with enlarged, weakly keeled, and weakly conical tubercles forming eight whorls; six tubercles on first whorl, four tubercles on second to fourth whorls, only a pair of paravertebral tubercles each on fifth to eighth whorls; rest of the tail lacking enlarged tubercles; median row of subcaudals smooth, roughly subcircular, distinctly enlarged than rest, with condition of two enlarged scales alternating with a divided scale. Males with ochre dorsum, single central black dorsal ocellus on neck, a white ocellus on ventrolateral side of neck and one on throat posterior to jaw, venter off-white with dark throat, tail unbanded, females and juveniles brown with a prominent mid-dorsal streak.

Comparisons with members of Cnemaspis beddomei clade.

Cnemaspis sathuragiriensis sp. nov. can be easily distinguished from all 16 members of the Cnemaspis beddomei clade as well as from C. boiei by a combination of the following differing or non-overlapping characters: A small-sized Cnemaspis , snout to vent length ≤ 33 mm (vs medium-sized Cnemaspis , snout to vent length 40-49 mm in C. nairi , C. nimbus , C. ornata , C. rashidi , C. rubraoculus and C. wallaceii ; large-sized Cnemaspis , snout to vent length> 50 mm in C. anamudiensis , C. beddomei , C. maculicollis , and C. smaug ; snout to vent length ≤ 38 mm in C. azhagu , C. boiei , and C. nigriventris ); 6-8 rows of dorsal tubercles at midbody (vs only a few enlarged scattered tubercles at midbody dorsum in C. anamudiensis , two or three rows of dorsal tubercles at midbody in C. azhagu , 16-18 in C. nairi , 13 or 14 in C. nigriventris , 12-14 in C. nimbus and C. ornata , 19-22 in C. smaug , 10 in C. vangoghi sp. nov., 14 or 15 in C. wallaceii ); 130-137 longitudinal ventral scales from mental to cloaca (vs 151-171 longitudinal ventral scales from mental to cloaca in C. azhagu , 154-161 in C. beddomei , 153-159 in C. galaxia , 143-147 in C. nairi , 154-159 in C. nigriventris , 157-165 in C. ornata , 170-172 in C. rashidi , 148-154 in C. regalis , 142-150 in C. smaug , 156-160 in C. sundara , 154-156 in C. wallaceii ); paravertebral tubercles either absent or irregular (vs 18 or 19 tubercles in paravertebral rows in C. aaronbaueri and C. beddomei , 16 or 17 in C. nimbus , 21-23 in C. ornata , 27-30 in C. smaug , 7-14 in C. vangoghi sp. nov., 18-20 in C. wallaceii ); 28-30 midventral scales across belly (vs 34-44 midventral scales across belly in C. azhagu , 32 or 33 in C. nairi , 38-40 in C. nigriventris , 26 or 27 in C. nimbus , 40-44 in C. regalis , 33-37 in C. rubraoculus , 35 or 36 in C. sundara ); a distinct white ocellus on ventrolateral sides of neck present in males (vs white ocellus on ventrolateral sides of neck absent in C. aaronbaueri , C. anamudiensis , C. azhagu , C. beddomei , C. maculicollis , C. nimbus , C. regalis , C. rubraoculus , C. smaug , C. wallaceii ); tail unbanded (tail distinctly banded in C. nairi , C. nigriventris , C. ornata , C. rashidi , C. smaug , C. sundara ).

Description of the holotype.

Adult male in good state of preservation except tail marginally bent towards right, hemipenis fully everted on right, and a 4.1 mm long incision in sternal region for tissue collection (Fig. 8A-E ); SVL 32.1 mm, head short (HL/SVL 0.27), wide (HW/HL 0.74), not strongly depressed (HD/HL 0.52), distinct from neck. Loreal region marginally inflated, canthus rostralis indistinct. Snout almost 1/2 of head length (ES/HL 0.44), 2 × eye diameter (ES/ED 2.2); scales on snout and canthus rostralis subcircular to elongate, subequal, smooth, weakly conical, much larger than those on forehead and interorbital region; scales on forehead similar to those on snout and canthus rostralis except almost 2 × smaller and elongate; scales on interorbital region, occipital, and temporal region even smaller, granular (Fig. 9A ). Eye small (ED/HL 0.20); with round pupil; supraciliaries short, larger anteriorly; seven interorbital scale rows across narrowest point of frontal bone; 29 scale rows between left and right supraciliaries at mid-orbit level (Fig. 9A, C ). Ear-opening deep, oval, small (EL/HL 0.05); eye to ear distance much greater than diameter of eye (EE/ED 1.61) (Fig. 9C ). Rostral slightly> 2 × as wide (1.7 mm) as high (0.8 mm), incompletely divided dorsally by a strongly developed rostral groove for> 1/2 of its height; a single enlarged, roughly rectangular supranasal on each side, almost 3 × larger than upper postnasal, and strongly in contact with each other on snout; a pair of enlarged scales on snout behind internasals, separated from each other by a single smaller, granular scale; rostral in contact with supralabial I, nostril, and supranasal on either side; nostrils oval, surrounded by three postnasals, supranasal, rostral and supralabial I on either side; three postnasals on either side, the one touching supranasal largest, roughly rectangular, gradually decreasing in side posteriorly; two single row of scales separate orbit from supralabials (Fig. 9C ). Mental enlarged, subtriangular, marginally wider (2.1 mm) than high (1.9 mm); two pairs of postmentals, inner pair roughly rectangular, shorter (1.0 mm) than mental, separated from each other below mental by a single enlarged median chin shield; inner pair bordered by mental, infralabial I, outer postmental, median chin shield and a single enlarged chin shields on either side; outer postmentals roughly rectangular, slightly smaller (0.6 mm) than inner pair, bordered by inner postmentals, infralabial I and II, and five enlarged chin shields on either side; three enlarged gular scales (including median chin shield) between left and right outer postmentals; all chin scales bordering postmentals more or less flattened, subequal, subcircular, smooth, and smaller than outermost postmentals; scales on rest of throat granular, smooth, subcircular, and juxtaposed scales (Fig. 9B ). Infralabials bordered below by a row or two of slightly enlarged, much elongated scales, decreasing in size posteriorly. Eight supralabials up to angle of jaw and five at midorbital position on each side; supralabial I largest, gradually decreasing in size posteriorly; seven infralabials up to angle of jaw and five at midorbital position on either side; infralabial I largest, gradually decreasing in size posteriorly (Fig. 9C ).

Body relatively slender (BW/AGL 0.50), trunk <1/2 of SVL (AGL/SVL 0.39) without spine-like tubercles on flank (Fig. 10A-C ). Dorsal pholidosis heterogeneous; smooth to weakly keeled granular scales intermixed with irregularly arranged rows of enlarged, weakly keeled, conical tubercles; granular scales gradually increasing in size towards each flank, largest on mid-flank; granular scales on occiput and nape slightly smaller than paravertebral granules; enlarged tubercles in approximately six longitudinal rows at midbody; enlarged tubercles in paravertebral rows absent, (Fig. 10A, C ). Ventral scales much larger than granular scales on dorsum, subequal from chest to vent, smooth, subcircular and subimbricate with rounded end; scales on precloacal region and four or five rows on femur distinctly enlarged; midventral scale rows across belly 30; 132 ventral scales from mental to anterior border of cloaca (Fig. 10B ). A continuous series of seven precloacal pores, femoral pores absent (Fig. 9D ).

Scales on palm and soles granular, smooth, rounded, and flattened, a distinct enlarged metacarpal scale on palm below digit I; scales on dorsal aspects of limbs heterogeneous in shape and size; scales on upper arm and thigh much larger than granular scales on body dorsum, smooth and a few feebly keeled, slightly elongate, subimbricate with weakly pointed ends; scales on lower arm and shank granular, similar in size to granular scales on body dorsum, smooth, rounded, gradually becoming larger, flattened and subimbricate anterolaterally and posteriorly, largest on anterolateral aspect of the hands and feet; scales on ventral aspect of upper arm smooth, granular, much smaller than granular scales on body dorsum, scales on ventral aspect of lower arm with much larger scales than those on upper arm, smooth, subcircular and flattened scales; ventral aspect of thigh and shank with enlarged, smooth, flattened, subimbricate scales, much larger than midventrals (Fig. 8A, B ). Forelimbs and hindlimbs slightly long, slender (LAL/ SVL 0.14); (CL/SVL 0.19); digits long, with a strong, recurved claw, distinctly inflected, distal portions laterally compressed conspicuously. Digits with both paired and unpaired lamellae, separated into a basal and narrower distal series by single enlarged lamella at inflection; one or two most basal paired on basal series and 1-4 paired lamellae above the inflection; basal lamellae series: (1-5-4-6-3 right manus, 1-6-7-8-2 right pes), (1-5-4-6-4 left manus, Fig. 9E ; 1 - 6 - 7 - 8 - 2 left pes, Fig. 9F ); distal lamellae series: (10-12-14-14-12 right manus, 10-12-16-16-16 right pes), (10-12-15-14-12 left manus, Fig. 9E ; 10-13-16-15-15 left pes, Fig. 9F ). Relative length of digits (measurements in mm in parentheses): IV (3.4) = III (3.4)> II (3.1)> V (3.0)> I (2.2) (left manus); IV (4.1) = III (4.1)> II (3.4) = II (3.3)> I (2.2) (left pes).

Tail mostly original with regenerated tip, entire, subcylindrical, slender, marginally longer than body (TL/SVL = 1.14) (Fig. 8C-E ). Dorsal pholidosis on tail heterogeneous; small, smooth, subcircular, flattened, subimbricate scales intermixed on anterior one third portion with enlarged, weakly keeled, and weakly conical tubercles forming eight whorls; six tubercles on first whorl, four tubercles on second to fourth whorls, only a pair of paravertebral tubercles each on fifth to eighth whorls; rest of the original and regenerated tail lacking enlarged tubercles (Fig. 8C, E ). Scales on tail venter much larger than those on dorsal aspect, smooth, roughly subcircular, flattened, subimbricate; median series smooth, roughly subcircular, distinctly enlarged than rest, with condition of two enlarged scales alternating with a divided scale (Fig. 8D ). Scales on tail base much smaller, smooth, imbricate; a single enlarged, smooth, and weakly conical postcloacal tubercle on each side (Fig. 8D, E ).

Colouration in life

(Fig. 11A ). Dorsal ground colour of body, limbs, and tail pale grey; neck and trunk ochre, fading slightly near hindlimb insertions. Pale blue-grey preorbital streak runs from nostril to orbit; three pale postorbital streaks, uppermost on either side meeting in parietal region forming an inverted chevron enclosing a single large elongate black ocellus on occiput, middle terminating on neck and lowermost continuing until ear opening. Head finely reticulated with pale blue-grey, a white ocellus on a black patch of scales on each side of ventrolateral aspect of neck just anterior to forelimb insertions; a fine yellow collar at anterior edge of forelimb insertions, broken in the centre, two fine black spots anterior to and a yellow spot on the division. Fine black spots and paler blotches on dorsum, tubercles and a few adjacent scales around hindlimb insertions and on tail pale blue-grey; similar spots on posterior flank, femur and bands on tibia; upper 1/2 of upper arm ochre, otherwise whitish-grey with dark outlines of scales; digits with white and dark markings. Original tail without bands, blue with dark outlines of scales and darker markings. Ventral ground colouration grey-white; throat fairly strongly marked with black up to forelimb insertions except for a fine pale border just below infralabials, a white spot on either side of the throat posterior to jaw; belly with scattered dark markings and blue-grey scales toward the lateral margins; underside of limbs and tail with few dark markings; precloacal and femoral region with almost no dark markings. Pupil black, iris dark red with a pale orange ring lining pupil.

Variation and additional information from type series

(Figs 11B, C , 12 ). Mensural, meristic, and additional character state data for the type series is given in Tables 3 - 5 , respectively. There are three adult males, and a single subadult female ranging in size from 26.7-33.0 mm (Fig. 12 ). All paratypes resemble the holotype except as follows: inner postmentals bordered by mental, infralabial I, outer postmental, enlarged median chin shield in all paratypes, additionally, bordered by two small chin scales on left and a single scale on right side in NRC-AA-8351. Outer postmentals bordered by inner pair, infralabial I & II in all paratypes, additionally, bordered by four chin scales on left and five on right side in NRC-AA-8350, four on left and five on right side in NRC-AA-8351 and NRC-AA-8353, four on either side in NRC-AA-8352; outer postmental separated from each other by four chin scales including median chin shield in NRC-AA-8351. NRC-AA-8350 with almost original tail with tip regenerated, marginally longer than body (TL/SVL 1.17), NRC-AA-8351 with original tail with missing tail tip, equal to body (TL/SVL 1.02); Two paratypes, NRC-AA-8352 and NRC-AA-8353 with completely missing tails; NRC-AA-8351 with damaged skink on the tail base; NRC-AA-8350 with fully everted hemipenis only on left side.

The new species is strongly sexually dichromatic and shows ontogenetic colour variation (Fig. 11A-C ): subadult female pale brown with a cream mid-dorsal streak that continues onto tail formed by the extension of the neck chevron, dorsum with scattered black and pale blotches, collar pale brown, flanked anteriorly by a few black spots; distinct black central ocellus on occiput, white ocelli on side of neck absent; forelimbs brown, hindlimbs with scattered dark and pale markings, digits banded. Original tail grey, without bands, regenerated portion blue in male paratypes. Ventral ground colouration of gular, body and tail grey-white; underside of limbs with few dark markings. Juveniles brown with a cream mid-dorsal streak that continues onto tail where it is orange formed by the extension of the neck chevron; distinct black central ocellus on occiput, white ocelli on side of neck absent; forelimbs brown, hindlimbs with scattered dark and pale markings, digits banded. Original tail grey, without bands, regenerated portion blue in male paratypes (Fig. 12A, B ). Ventral ground colouration of gular, body and tail grey-white; underside of limbs with few dark markings.

Etymology.

The specific epithet is a toponym for the type locality of the new species, Sathuragiri mountain in Srivilliputhur-Megamalai Tiger Reserve (SMTR), Virudhunagar District, Tamil Nadu. Suggested Common name is Sathuragiri dwarf gecko.

Distribution and natural history.

Cnemaspis sathuragiriensis sp. nov. is known only from its type locality (Sathuragiri hills in Virudhunagar district, Tamil Nadu) between elevations of 250-400 m a.s.l. on eastern slopes of the Western Ghats (Fig. 1 ). Individuals of the new species were observed active during the daytime (0830-1100 hrs) on rocks and tree trunks <2 m high from the base in seasonally dry tropical forest with a mix of evergreen and deciduous species (Fig. 13A ). The species was observed in high abundance (n ≥ 20/hr), more commonly on boulders in shaded areas than tree trunks (Fig. 13B ). Sympatric lizards at the type locality include Cnemaspis cf. gracilis , Hemidactylus cf. frenatus , H. cf. leschenaultii , H. vanam , Dravidoseps srivilliputhurensis , Eutropis carinata , E. macularia , and Psammophilus cf. blanfordanus .

Figures

Figure 1. Maximum likelihood phylogeny of the Cnemaspis beddomei clade (ND 2 + 16 S concatenated, 1610 base pairs) with photographs of the new species and C. galaxia (not to scale); numbers at nodes represent bootstrap support / posterior probability> 70 / 0.99 (not shown close to terminal nodes). Inset, elevation map of the southern Western Ghats showing type and sampled localities for the Cnemaspis ornata subclade.

Figure 2. Cnemaspis vangoghi sp. nov. (holotype, NRC-AA- 8342) A dorsal view of body B ventral view of body C dorsal view of tail D ventral view of tail E lateral view of tail. Photos by Akshay Khandekar. Scale bars: 10 mm.

Figure 6. Paratype series of Cnemaspis vangoghi sp. nov., from left to right, NRC-AA- 8343 - 8348 A dorsal view, and B ventral view. Photos by Akshay Khandekar. Scale bar: 10 mm.

Figure 7. Habitat of Cnemaspis vangoghi sp. nov. A general view at Settur Reserve Forest (paratype locality), and B microhabitat at type locality. Photos by Akshay Khandekar.

Figure 8. Cnemaspis sathuragiriensis sp. nov. (holotype, NRC-AA- 8349) A dorsal view of body B ventral view of body C dorsal view of tail D ventral view of tail E lateral view of tail. Photos by Akshay Khandekar. Scale bars: 10 mm.

Figure 9. Cnemaspis sathuragiriensis sp. nov. (holotype, NRC-AA- 8349) A dorsal view of head B ventral view of head C lateral view of head on right D view of femoral region showing femoral pores E ventral view of left manus F ventral view of left pes. Photos by Akshay Khandekar. Scale bars: 5 mm.

Figure 10. Cnemaspis sathuragiriensis sp. nov. (holotype, NRC-AA- 8349) A dorsal view of midbody B ventral view of midbody C lateral view of midbody. Photos by Akshay Khandekar. Scale bars: 5 mm.

Figure 11. Cnemaspis sathuragiriensis sp. nov., in life A adult male (holotype, NRC-AA- 8349) B subadult female (paratype, NRC-AA- 8353), and C juvenile (uncollected). Photos by Akshay Khandekar.

Figure 12. Paratype series of Cnemaspis sathuragiriensis sp. nov., from left to right, NRC-AA- 8350 - 8353 A dorsal view, and B ventral view. Photos by Akshay Khandekar. Scale bars: 10 mm.

Figure 13. Habitat of Cnemaspis sathuragiriensis sp. nov. at the type locality A general view, and B microhabitat from where types were collected. Photos by Akshay Khandekar.