Cnemaspis vangoghi, 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 vangoghi sp. nov.

Figs 2 , 3 , 4 , 5 , 6

Type material examined.

Holotype. NRC-AA-8342 (AK-R 1356), adult male, from near Neer Katha Ayyanar Kovil (9.5108°N, 77.4529°E; ca 250 m a.s.l.), Srivilliputhur-Meghamalai Tiger Reserve, Virudhunagar district, Tamil Nadu state, India; collected by Akshay Khandekar, Ishan Agarwal, Swapnil Pawar and team on 16 April 2022. Paratypes. NRC-AA-8343 (AK-R 1351), NRC-AA-8344 (AK-R 1352), adult males, same data as holotype; NRC-AA-8345 (AK-R 1358), adult female, from near Ayyanar Kovil waterfalls (9.5200°N, 77.4478°E; ca 400 m a.s.l.), same data as holotype; NRC-AA-8346 (AK-R 1373), NRC-AA-8347 (AK-R 1374), NRC-AA-8348 (AK-R 1380), adult males, from Settur Reserve Forest (9.4036°N, 77.3721°E; ca 350 m a.s.l.), same data as holotype except collected on 17 April 2022.

Diagnosis.

A small-sized Cnemaspis , snout to vent length ≤ 34 mm (n = 7). Dorsal pholidosis heterogeneous; smooth to weakly keeled granular scales intermixed with fairly regularly arranged rows of enlarged, weakly keeled, conical tubercles; 10 rows of dorsal tubercles at midbody, 7-14 tubercles in paravertebral rows; ventral scales subequal from chest to vent, smooth, subcircular and subimbricate with rounded end; 29-31 midventral scales across belly, 125-140 longitudinal ventral scales from mental to cloaca; subdigital scansors smooth, unnotched, some divided and others entire, a distinct enlarged metacarpal scale below digit I; 11-14 lamellae under digit I of manus and 11-13 under digit I of pes, 19-22 lamellae under digit IV of manus and 18-25 lamellae under digit IV of pes; males with continuous series of six or seven precloacal pores (n = 6); 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 seven whorls; six tubercles on first three whorl, four tubercles on fourth to seventh whorls, only a pair of paravertebral tubercles each on eighth to 11th whorls; rest of the tail lacking enlarged tubercles; median row of subcaudals smooth, roughly rectangular, distinctly enlarged, with condition of two enlarged scales alternating with a divided scale. Males with ochre anterior 1/2 of body, 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, juveniles with indistinct mid-dorsal streak.

Comparisons with members of Cnemaspis beddomei clade.

Cnemaspis vangoghi 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 ≤ 34 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 ); ten 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 , eight in C. galaxia , 16-18 in C. nairi , 13 or 14 in C. nigriventris , 12-14 in C. nimbus and C. ornata , 7-9 in C. regalis , 19-22 in C. smaug , six in C. sundara , 14 or 15 in C. wallaceii ); 125-140 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 ); 7-14 tubercles in paravertebral rows (vs paravertebral tubercles either absent or irregular in C. anamudiensis , C. azhagu , and C. sundara , 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 , 18-20 in C. wallaceii ); 29-31 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. 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 ). Cnemaspis vangoghi sp. nov. is diagnosed against the other new species as part of its description below.

Description of the holotype.

Adult male in good state of preservation except tail marginally bent towards left and tip is missing, hemipenis partially everted on right and fully on left side, and a 3.1 mm long incision in sternal region for tissue collection (Fig. 2A, B ); SVL 32.1 mm, head short (HL/SVL 0.25), wide (HW/HL 0.68), not strongly depressed (HD/HL 0.40), distinct from neck. Loreal region marginally inflated, canthus rostralis indistinct. Snout 1/2 head length (ES/HL 0.48), 2.5 × eye diameter (ES/ED 2.5); 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. 3A ). Eye small (ED/HL 0.19); with round pupil; supraciliaries short, larger anteriorly; eight interorbital scale rows across narrowest point of frontal bone; 27 scale rows between left and right supraciliaries at mid-orbit level (Fig. 3A ). Ear-opening deep, oval, small (EL/ HL 0.06); eye to ear distance much greater than diameter of eye (EE/ED 1.60) (Fig. 3C ). Rostral slightly> 2 × as wide (1.5 mm) as high (0.7 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 two much smaller, granular scales; rostral in contact with supralabial I, nostril, and supranasal on either side; nostrils oval, surrounded by four postnasals, supranasal, rostral and supralabial I on either side; four roughly circular postnasals on either side, the one touching supranasal largest, gradually decreasing in side posteriorly; two single row of scales separate orbit from supralabials (Fig. 3C ). Mental enlarged, subtriangular, marginally wider (2.0 mm) than high (1.6 mm); two pairs of postmentals, inner pair roughly rectangular, shorter (0.9 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 four enlarged chin shields on either side; three enlarged gular scales between left and right outer postmentals; all chin scales bordering postmentals more or less flattened, subcircular, smooth, and smaller than outermost postmentals; scales on rest of throat, much smaller, smooth, subcircular, and subimbricate (Fig. 3B ). Infralabials bordered below by a row or two of slightly enlarged, much elongated scales, decreasing in size posteriorly. Nine supralabials up to angle of jaw and five at midorbital position on each side; supralabial I largest, gradually decreasing in size posteriorly; eight infralabials on left and seven on right side up to angle of jaw, four at midorbital position on left and five on right side; infralabial I largest, gradually decreasing in size posteriorly (Fig. 3C ).

Body relatively slender (BW/AGL 0.37), trunk <1/2 of SVL (AGL/SVL 0.42) without spine-like tubercles on flank (Fig. 4A-C ). Dorsal pholidosis heterogeneous; smooth to weakly keeled granular scales intermixed with a fairly regularly 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 10 longitudinal rows at midbody; 12 (left) and 14 (right) tubercles in paravertebral rows (Fig. 4A, 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 31; 138 ventral scales from mental to anterior border of cloaca (Fig. 4B ). A continuous series of six precloacal pores, femoral pores absent (Fig. 3D ).

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, elongate, subimbricate with 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. 2A, 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: (1-5-5-6-5 right manus, 2-7-7-7-4 right pes), (2-6-5-6-5 left manus, Fig. 3E ; 2-7-7-8-3 left pes, Fig. 3F ); distal lamellae series: (11-12-16-15-12 right manus, 10-12-16-16-16 right pes), (11-12-15-15-12 left manus, Fig. 3E ; 10-12-16-16-16 left pes, Fig. 3F ). Relative length of digits (measurements in mm in parentheses): IV (3.2)> III (3.1)> II (2.9)> V (2.7)> I (2.1) (left manus); IV (4.1)> V (3.9) = III (3.6)> II (2.9)> I (1.9) (left pes).

Tail original, subcylindrical, slender, not entire, tail tip is detached and missing, TL = 27.2 mm (Fig. 2C-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 seven whorls; six tubercles on first three whorl, four tubercles on fourth to seventh whorls, only a pair of paravertebral tubercles on 8th to 11th whorls; rest of the tail lacking enlarged tubercles (Fig. 2C, E ). Scales on tail venter much larger than those on dorsal aspect, smooth, roughly subcircular, flattened, subimbricate; median series smooth, roughly rectangular, distinctly enlarged than rest, with condition of two enlarged scales alternating with a divided scale (Fig. 2D ). Scales on tail base much smaller, smooth, imbricate; a single enlarged, smooth and weakly conical postcloacal tubercle on each side (Fig. 2D, E ).

Colouration in life

(Fig. 5A ). Dorsal ground colour of body, limbs and tail light grey; neck to mid-body ochre, fading slightly at mid-body. Light blue-grey preorbital streak runs from nostril to orbit; three light 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, just divided by indistinct continuation of chevron on neck, two small black spots anterior to the division. No distinct dorsal spots or bands, tubercles and a few adjacent scales at mid-body and posterior 1/2 of body pale blue-grey; similar spots on femur and bands on tibia; forelimbs with some ochre near insertions, otherwise whitish-grey with dark outlines of scales; digits with white and dark markings. Original tail without bands, blue-grey with dark outlines of scales. Ventral ground colouration grey-white; throat 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 dark markings and blue-grey scales toward the lateral margins; underside of limbs and tail with few dark markings; precloacal, femoral and tibial regions with almost no dark markings. Pupil black, iris reddish with a pale orange ring lining pupil.

Variation and additional information from type series

(Figs 5B, C , 6 ). Mensural, meristic and additional character state data for the type series is given in Tables 3 - 5 , respectively. There are four adult males, a single subadult male, and a single adult female ranging in size from 28.6-33.6 mm (Fig. 6A, B ). All paratypes resemble the holotype except as follows: three postnasals on either side in NRC-AA-8344, NRC-AA-8346, and NRC-AA-8348. Inner postmentals bordered by mental, infralabial I, outer postmental, enlarged median chin shield in all paratypes, additionally, bordered by two small chin scales on either side in NRC-AA-8343, single chin scale on left and two on right side in NRC-AA-8344. Outer postmentals bordered by inner pair, infralabial I and II in all paratypes, additionally, bordered by five chin scales on left and four on right side in NRC-AA-8344, NRC-AA-8345, NRC-AA-8347; four on left and five on right side in NRC-AA-8348; outer postmental separated from each other by five chin scales including median chin shield in NRC-AA-8343, four chin scales in NRC-AA-8344. NRC-AA-8348 with original and complete tail, slightly longer than body (TL/SVL 1.23); three paratypes, NRC-AA-8344, NRC-AA-8346, and NRC-AA-8347, with original partially broken tails; NRC-AA-8343 with small and partially regenerated tail, and NRC-AA-8345 with complete regenerated tail, detached from the body (Fig. 6A, B ). NRC-AA-8347 with damaged skink on the snout; NRC-AA-8343 with fully everted hemipenis on either side, NRC-AA-8347 with fully everted hemipenis only on left side.

The new species is strongly sexually dimorphic and also shows ontogenetic colour variation (Fig. 5A-C ): females brown with numerous black and pale blotches, collar pale brown, flanked anteriorly by thick black, divided by an extension of the neck chevron; distinct black ocellus on occiput; white ocelli on side of neck absent; forelimbs brown, hindlimbs with scattered dark and pale markings, digits banded. Regenerated tail grey, without bands. Ventral ground colouration of gular, body and tail grey-white; underside of limbs with few dark markings. Subadult male brown with an indistinct, cream mid-dorsal streak formed by the extension of the neck chevron, five or six spots in the streak; black ocellus on occiput and white ocelli on side of neck distinct; forelimbs brown, hindlimbs with scattered dark and pale markings, digits banded. Original tail without bands, grey with dark outlines of scales, regenerated portion brown. Ventral ground colouration of gular, body and tail grey-white; a white spot on either side of the throat posterior to jaw; belly without dark markings; underside of limbs and tail with few dark markings.

Etymology.

The specific epithet is a patronym for Dutch painter Vincent Van Gogh (1853-1890). The colouration of the new species is reminiscent of one of Van Gogh’s most iconic paintings, The Starry Night. Suggested common name is Van Gogh’s starry dwarf gecko.

Distribution and natural history.

Cnemaspis vangoghi sp. nov. is known only from two closely spaced localities (Ayyanar Kovil and Settur Reserve Forest, both in Meghamalai-Srivilliputhur Tiger Reserve, Tamil Nadu) within <15 km straight line distance (Fig. 1 ). The new species was recorded in seasonally dry tropical forest with a mix of evergreen and deciduous species between elevations of 250-400 m a.s.l. on eastern slopes of the Western Ghats (Fig. 7A ). Individuals of the new species were observed active during the daytime (0830-1400 hrs) on rocks and tree trunks <2 m high from the base (Fig. 7B ). A large number of individuals (n ≥ 25/hr) were observed at both the locations indicating high abundance. At Ayyanar Kovil, a few individuals were observed inactive, resting on rocks during evening and night time (1800-2030 hrs). We also observed Giant wood spider ( Nephila sp.) feeding on an adult female individual of the new species. Sympatric lizards at the type locality include Cnemaspis cf. gracilis , Hemidactylus cf. frenatus , H. cf. leschenaultii , H. vanam Chaitanya, Lajmi & Giri, 2018, Dravidoseps srivilliputhurensis Agarwal, Thackeray & Khandekar, 2024, Eutropis carinata (Schneider, 1801), E. macularia (Blyth, 1853), 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 3. Cnemaspis vangoghi sp. nov. (holotype, NRC-AA- 8342) 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 4. Cnemaspis vangoghi sp. nov. (holotype, NRC-AA- 8342) A dorsal view of midbody B ventral view of midbody C lateral view of midbody. Photos by Akshay Khandekar. Scale bars: 5 mm.

Figure 5. Cnemaspis vangoghi sp. nov., in life A adult male (holotype, NRC-AA- 8342) B adult female (paratype, NRC-AA- 8345), and C subadult male (paratype, NRC-AA- 8348). Photos by Akshay Khandekar.

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.