Cnemaspis sanctus, Khandekar & Thackeray & Agarwal, 2024

Khandekar, Akshay, Thackeray, Tejas & Agarwal, Ishan, 2024, Two new nocturnal species of South Asian Cnemaspis Strauch, 1887 (Squamata: Gekkonidae) of the wynadensis clade from the southern Western Ghats, India, Zootaxa 5443 (3), pp. 353-386 : 369-380

Cnemaspis sanctus sp. nov.

urn:lsid:zoobank.org:act:C76F88A6-3CCB-4F7E-94B1-18B3EA444F72

( Figs 8–12 ; Tables 6–8 )

Holotype. NRC-AA-8363 ( AK-R 1123 ), adult male, from near Kaalimala Durgadevi Temple (8.46623°N, 77.22640°E; ca. 520 m asl.), Pathukani, Kanyakumari District , Tamil Nadu State, India; collected by Akshay Khandekar, Ishan Agarwal, Swapnil Pawar and team on 6 th April 2022.

Paratypes. NRC-AA-8370 ( AK-R 1121 ), adult female, NRC-AA-8371 ( AK-R 1122 ) juvenile, same data as holotype ; NRC-AA-8364 ( AK-R 1115 ), NRC-AA-8365 ( AK-R 1116 ) adult males, NRC-AA-8366 ( AK-R 1117 ) subadult female, from near Kaalimala Hiking point (8.47266°N, 77.22780°E; ca. 400 m asl.) ; NRC-AA-8367 ( AK-R 1118 ) adult male, NRC-AA-8368 ( AK-R 1119 ), NRC-AA-8369 ( AK-R 1120 ) adult females, from near Thekkan Kurusumalai Pilgrim Center (8.469434°N, 77.22132°E; ca. 600 m asl.) ; NRC-AA-8372 ( AK-R 1124 ) adult female, NRC-AA-8373 ( AK-R 1125 ) juvenile, from near AK Plantations (8.46360°N, 77.23465°E; ca. 300 m asl.) ; same data as holotype .

Etymology. The specific epithet is the Latin noun sanctus , one who is holy or saintly, used in apposition (hence invariable) and alludes to the fact that the type locality has both a temple and a church close together.

Suggested Common Name. Holy dwarf gecko.

Diagnosis. A medium-sized Cnemaspis , maximum snout to vent length up to 45.2 mm (n = 11). Dorsal pholidosis homogeneous; weakly keeled granules which are smallest on paravertebral region, increasing in size laterally towards flank, largest on mid flank, gradually decreasing in size ventrolaterally; 47–53 granules around the body at midbody, ventral scales subequal from chest to vent, smooth, subcircular and subimbricate with rounded end; 20–25 scales across belly at midbody, 118–135 longitudinal scales from mental to cloaca; subdigital scansors smooth, unnotched, some divided and others entire, a slightly enlarged metacarpal scale below digit I; 12–14 lamellae under digit I of manus and 11–14 under digit I of pes, 17–21 lamellae under digit IV of manus and 20–24 lamellae under digit IV of pes; males with 3–5 femoral pore series on each thigh separated by 18–21 poreless scales (n = 5/11); scales on non-regenerated tail dorsum homogeneous; small, smooth, subcircular, flattened, and subimbricate scales, gradually increasing in size laterally; median row of subcaudals smooth, roughly rectangular, distinctly enlarged with a few irregularly arranged divided and/or entire, even enlarged scales in-between; postcloacal tubercle absent. No sexual dichromatism; dorsal colouration brown, a black spot on nape, light streak running through eye and onto dorsum, light middorsal streak with indistinct small light and black middorsal spots; anterior half of tail with alternating irregular light and dark bands, tip black. Juveniles dark with a prominent light Y-shaped marking on the head and dorsum, tail orange.

Comparisons with members of wynadensis clade. Cnemaspis sanctus sp. nov. can be easily distinguished from all 11 members of the wynadensis clade and C. bireticulata by a combination of the following differing or non-overlapping characters: A medium-sized Cnemaspis , snout to vent length up to 45.2 mm (versus large-sized Cnemaspis , snout to vent length <50 mm in C. anaikattiensis , C. lithophilis , C. magnifica , C. sisparensis , and C. zacharyi ; snout to vent length 40 mm or lower in C. persephone sp. nov. and C. wynadensis ); dorsal pholidosis homogeneous consisting of granules that are smallest on paravertebral region and largest on mid flank (versus dorsal pholidosis heterogeneous consisting of granules intermixed with enlarged tubercles in C. anaikattiensis , C. bireticulata , C. chengodumalaensis , C. heteropholis , C. kottiyoorensis , C. lithophilis , C. magnifica , and C. wynadensis ); 20–25 ventral scales across belly at midbody (versus 28–32 ventral scales across belly at midbody in C. anaikattiensis , 26 in C. bireticulata , and 27–30 in C. sisparensis ); 118–135 longitudinal ventral scales from mental to cloaca (versus 147–153 longitudinal ventral scales from mental to cloaca in C. anaikattiensis , 141–150 in C. chengodumalaensis , 133–160 in C. magnifica , 139–143 in C. sisparensis , and 150–153 in C. zacharyi ); males with 3–5 femoral pore series on each thigh separated by 18–21 poreless scales (versus males with seven or eight femoral pores on each thigh separated by 15 or 16 poreless scales in C. anaikattiensis , eight to nine femoral pores separated by 14–16 poreless scales in C. balerion , seven or eight femoral pores separated by 16 poreless scales in C. bireticulata , 6–8 femoral pores separated by 14–16 poreless scales in C. chengodumalaensis , six or seven femoral pores separated by 15 or 16 poreless scales in C. magnifica , five or six femoral pores separated by 13 poreless scales in C. persephone sp. nov., seven or eight femoral pores separated by 17–19 poreless scales in C. sisparensis , five or six femoral pores separated by 22–24 poreless scales in C. zacharyi , and a continuous series of 24–28 precloaco-femoral pores in C. kolhapurensis ); 47–53 granules around the body at midbody (versus 40–43 granules around the body at midbody in C. persephone sp. nov.).

Description of the holotype. Adult male in good state of preservation except tail and head bent towards right side, a small patch of skin (3.5 and 2.2 mm) missing at base of right forelimb on dorsal side and on precloacal region respectively, and a 2.6 mm long incision in sternal region for tissue collection ( Fig. 8A, B ); SVL 36.7 mm, head short (HL/SVL 0.24), wide (HW/HL 0.69), not strongly depressed (HD/HL 0.42), distinct from neck. Loreal region marginally inflated, canthus rostralis indistinct. Snout half of head length (ES/HL 0.46), almost 2.5 times eye diameter (ES/ED 2.36); scales on snout and canthus rostralis somewhat elongate, weakly conical, subequal, smooth to weakly keeled, much larger than those on forehead and interorbital region; scales on forehead similar to those on snout and canthus rostralis except smaller; scales on interorbital region, occipital, and temporal region even smaller, granular ( Fig. 9B ). Eye small (ED/HL 0.19); with round pupil; supraciliaries short, larger anteriorly; 13 interorbital scale rows across narrowest point of frontal bone; 33 scale rows between left and right supraciliaries at mid-orbit ( Fig. 9C ). Ear-opening deep, oval, small (EL/ HL 0.08); eye to ear distance much greater than diameter of eye (EE/ ED 1.57) ( Fig. 9C ). Rostral much wider (1.7 mm) than high (1.0 mm), incompletely divided dorsally by a strongly developed rostral groove and a slightly enlarged internasal scale for more than half of its height; a single enlarged, roughly rectangular supranasal on each side, almost three times larger than upper postnasal, and separated from each other by a slightly smaller internasal scale; rostral in contact with supralabial I, nostril, supranasal, and internasal on either side; nostrils oval, surrounded by two postnasals, supranasal, rostral and supralabial I on either side; two roughly circular postnasals on either side, the one touching supranasal more than twice larger than lower, not in contact with lower postnasal; two single row of scales separate orbit from supralabials ( Fig. 9A, C ). Mental enlarged, subtriangular, slightly wider (2.0 mm) than high (1.5 mm); two pairs of postmentals, inner pair roughly triangular, much shorter (0.7 mm) than mental, separated from each other below mental by an enlarged median chin shield; inner pair bordered by mental, infralabial I, outer postmental, median chin shield, and a two slightly enlarged chin shields on left and three on right side; outer postmentals roughly rectangular, slightly smaller (0.5 mm) than inner pair, bordered by inner postmentals, infralabial I and II, and four enlarged chin shields on left and three on right side; six slightly enlarged gular scales between left and right outer postmentals; all chin scales bordering postmentals more or less flattened, subcircular, smooth, juxtaposed, and much smaller than outermost postmentals; scales on rest of gular region and throat, even smaller, flattened, subcircular, smooth, and juxtaposed ( 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 on either side, and five on left and six on right side at midorbital position; supralabial I largest, gradually decreasing in size posteriorly; eight infralabials up to angle of jaw on either side, and five at midorbital position on either side; infralabial I largest, gradually decreasing in size posteriorly ( Fig. 9C ).

Body relatively slender (BW/AGL 0.38), trunk marginally less than half of SVL (AGL/SVL 0.45) without spine-like tubercles on flank ( Fig. 10A–C ). Dorsal pholidosis homogeneous; weakly keeled granules which are smallest on paravertebral region and increasing in size towards either side of flank, largest on mid flank, gradually decreasing in side ventrolaterally; granules on occiput and nape slightly smaller than paravertebral granules; 50 granules around the body at midbody ( Fig. 10A ). Ventral scales much larger than granules on dorsum, subequal from chest to vent, smooth, subcircular and subimbricate with rounded to weakly pointed ends; scales on precloacal region and femur marginally enlarged; midbody scale rows across belly 23; 125 scales from mental to anterior border of cloaca ( Fig. 10B ). Precloacal pores absent, femoral pores elongate, four on each thigh, separated medially by 21 poreless scales ( Fig. 9D ).

Scales on palm and soles granular, smooth, rounded, and flattened, a slightly enlarged metacarpal scale on palm below digit I; scales on dorsal aspects of limbs homogeneous; weakly keeled and slightly larger than those on paravertebral region; dorsal scales on forelimb slightly smaller than those on hind limb; those on wrist weakly keeled, flattened and subimbricate; scales on ventral aspect of upper arm smooth, granular, much smaller than granules on paravertebral region, scales on ventral aspect of lower arm with much larger scales than those on upper arm, smooth, subcircular and subimbricate scales, much smaller than midbody ventrals; ventral aspect of thigh and shank with enlarged, smooth, flattened, subimbricate scales, marginally larger than body ventrals ( Fig. 8A, B ). Forelimbs and hindlimbs slightly long, slender (LAL/ SVL 0.14); (CL/SVL 0.16); 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 paired on basal series, and 1–4 paired lamellae above the inflection; basal lamellae series: (3-4-4-6-2 right manus, Fig. 9E ; 3-5-5-5-2 right pes), (3-4-3-5-2 left manus, 3-5-5-5-2 left pes, Fig. 9F ); distal lamellae series: (10- 13-15-15-14 right manus, Fig. 9E ; 10-13 -16-17-17 right pes), (11-13-15-15-14 left manus; 10-13-16-16-15 left pes, Fig. 9F ). Relative length of digits (measurements in mm in parentheses): IV (3.6)> III (3.5)> II (3.3)> V (3.2)> I (2.5) (left manus); IV (4.8)> V (4.3)> III (4.1)> II (3.7)> I (2.2) (left pes).

Tail original, subcylindrical, slender, entire, slightly longer than body (TL/SVL = 1.19) ( Fig. 8C, D ). Dorsal pholidosis on tail homogeneous; small, smooth, subcircular, flattened, and subimbricate scales, gradually increasing in size laterally ( Fig. 8C ). 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 a few irregularly arranged divided scales in-between ( Fig. 8D ). Tail base with much smaller, smooth, subimbricate scales; postcloacal tubercle absent on either side ( Fig. 8D ).

Colouration in life ( Fig. 11A ). Dorsal ground colour of head, body, limbs and tail brown; head with small black spots and thick light brown reticulations on parietal region, two light brown preorbital streaks from eye to nostril enclosing black streak, a light brown postorbital streak flanked by black that continues till forelimb insertions; supralabials and infralabials olive brown; two lighter streaks running ventrolaterally from angle of jaw onto throat. A small black spot on the occiput and a larger one on the neck; followed by seven faint small light grey middorsal spots alternating with four smaller dark markings near tail base; seven indistinct cross-bars extending slightly outward from middorsal streak flanked by darker markings; flanks mottled with black, brown, light grey, straw and white; tail with alternating irregular light and dark bands and mottled posterior half. Pupil black outlined by thin, orange iris. Limbs with scattered dark spots and lighter bands, digits alternating with light and dark bands. Ventrals pale grey; throat, underside of neck and limbs, and edges of belly with thick reticulation of black; one or two rows of scales bordering infralabials and postmentals off-white. Ventral surface of tail light grey with fine dark border of scales.

Variation and additional information from the paratype series. Mensural, meristic and additional character state data of the type series is given in Tables 6–8 respectively. There are four adult males, three adult females, one subadult female, and two juvenile specimens ranging in size from 21.7–45.2 mm ( Figs 11B, C ; 12A, B ). All paratypes resemble the holotype except as follows: rostral divided dorsally by two internasal scales for almost half of its height in NRC-AA-8372. Inner postmental separated from each other below mental by enlarged median chin shield and a slightly smaller chin scale in NRC-AA-8367, NRC-AA-8369, NRC-AA-8371, NRC-AA-8373; inner postmentals bordered by mental, infralabial I, outer postmental and median chin shield in all paratypes, additionally, by three slightly enlarged chin shields on either side in NRC-AA-8364 and NRC-AA-8367, two slightly enlarged chin shields on either side in NRC-AA-8365, NRC-AA-8366, NRC-AA-8370 and NRC-AA-8371, four slightly enlarged chin shields on left and two on right side in NRC-AA-8369. The type of scales and their numbers bordering outer postmentals are variable in all paratypes. Four paratypes —NRC-AA-8366, NRC-AA-8367, NRC-AA-8370 and NRC-AA-8372 with original and complete tail, slightly longer than body (TL/ SVL 1.16 , 1.18 , 1.11 and 1.12 respectively); two paratypes —NRC-AA-8369 and NRC-AA-8371 with entire but partially regenerated tails, slightly longer than or equal to body (TL/ SVL 1.11 and 0.99 respectively); three paratypes —NRC-AA-8364, NRC-AA-8365 and NRC-AA-8368 with complete but fully regenerated tail, slightly shorter than body (TL/ SVL 0.85, 0.83 and 0.82 respectively); and NRC-AA-8373 with completely broken and missing tail. Both males and females in the type series have similar colouration in varying shades of brown, regenerated portion of the tail being dark brown ( Figs 11B, C ; 12A, B ). The new species shows ontogenetic colour variation where juveniles and subadults are dark brown with a prominent light straw-coloured Y-shaped marking formed by a streak bordered by black that runs from the nostril through the eye and onto the dorsum meeting at forelimb insertions and continuing as a broad light straw middorsal streak with fine black middorsal spots, limbs light grey, tail suffused with orange

Distribution and natural history. Cnemaspis sanctus sp. nov. is currently known only from around its type locality, Kaalimalai in Pathukani, Kanyakumari District, Tamil Nadu ( Fig. 1 ). The new species was predominantly seen in evergreen forest patches between elevations of 300–600 m asl.. on western slopes of the Western Ghats ( Fig. 13A ). Individuals of the new species were observed active only after dusk (1830–2000 hrs) emerging from low (<100 cm height) stone walls and rock crevices. ( Fig. 13B ). A large number of individuals (n => 15/hr) were observed at all the sampled locations indicating high abundance. Sympatric lizards at the type locality include Cnemaspis cf. australis , Hemidactylus cf. frenatus , H. cf. leschenaultii , Eutropis carinata , E. brevis , Ristella sp. , and Monilesaurus cf. ellioti .

Note. The material from southern side of Kanyakumari District, that is <28 km south (Valli Chunai) and <20 km south east (Jeyasekharan estate) in straight-line distance from the type locality of C. sanctus sp. nov., is> 5 % divergent in ND2 sequence data from Cnemaspis sanctus sp. nov., higher than the 3.7 % cutoff proposed by Agarwal et al. (2017) and of similar levels to some recently described species (e.g. Agarwal et al. 2022). However, this population cannot be diagnosed using colouration ( Fig. 14 ), morphological data ( Tables 9–11 ), nor sizeadjusted mensural data (not shown). The only significantly different measurements/ ratios were of EN/ ES and IN/ ES, suggesting subtle differences in head shape (not shown). We refer to this population as Cnemaspis cf. sanctus pending further data, which is distributed at elevations between 150–600 m asl. in moist deciduous forest at Valli Chunai and a plantation in evergreen forest in Jeyasekharan Estate, Kanyakumari District, Tamil Nadu (Appendix 1). These populations are also nocturnal and were observed emerging from stone walls after dark at high abundance (n => 15).

Figures

FIGURE 1. Elevation map of Peninsular India portraying the Western Ghats showing type and additional sampled localities of the wynadensis clade and the Palghat Gap; left, Maximum Likelihood phylogeny of the wynadensis clade (ND2 + 16S concatenated, 1589 base pairs); numbers at nodes represent bootstrap support/ posterior probability>70/0.99 (not shown close to terminal nodes).

FIGURE 3. Cnemaspis persephone sp. nov. (holotype, NRC-AA-8354): (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, and (F) ventral view of left pes. Scale bars 5 mm; photos by Akshay Khandekar.

FIGURE 4. Cnemaspis persephone sp. nov. (holotype, NRC-AA-8354): (A) dorsal view of midbody, (B) ventral view of midbody, and (C) lateral view of midbody. Scale bars 5 mm; photos by Akshay Khandekar.

FIGURE 5. Cnemaspis persephone sp. nov. in life: (A) adult male (holotype, NRC-AA-8354), (B) adult female (paratype, NRC-AA-8356), and (C) subadult female (paratype, NRC-AA-8360). Photos by Swapnil Pawar (A) and Akshay Khandekar (B, C).

FIGURE 8. Cnemaspis sanctus sp. nov. (holotype, NRC-AA-8363): (A) dorsal view of body, (B) ventral view of body, (C) dorsal view of tail, and (D) ventral view of tail. Scale bars 10 mm; photos by Akshay Khandekar.

FIGURE 9. Cnemaspis sanctus sp. nov. (holotype, NRC-AA-8363): (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 right manus, and (F) ventral view of left pes. Scale bars 5 mm; photos by Akshay Khandekar.

FIGURE 10. Cnemaspis sanctus sp. nov. (holotype, NRC-AA-8363): (A) dorsal view of midbody, (B) ventral view of midbody, and (C) lateral view of midbody. Scale bars 5 mm; photos by Akshay Khandekar.

FIGURE 11. Cnemaspis sanctus sp. nov., in life: (A) adult male (holotype, NRC-AA-8363), (B) adult female (paratype, NRC- AA-8367), and (C) juvenile (paratype, NRC-AA-8371). Photos by Akshay Khandekar.

FIGURE 12. Paratype series of Cnemaspis sanctus sp. nov., from left to right, NRC-AA-8364–8370, NRC-AA-8372: (A) dorsal view and (B) ventral view. NRC-AA-8371 and NRC-AA-8373 are not shown. Scale bars 10 mm; photos by Akshay Khandekar.

FIGURE 13. Habitat of Cnemaspis sanctus sp. nov. at the type locality: (A) general view, and (B) microhabitat from where some paratypes were collected. Photos by Ishan Agarwal.

FIGURE 14. Specimens of Cnemaspis cf. sanctus used in the study: (A) dorsal view and (B) ventral view. Scale bars 10 mm; photos by Akshay Khandekar.