Cnemaspis nanayakkarai, Karunarathna & Ukuwela & De Silva & Bauer & Madawala & Poyarkov & Botejue & Gabadage & Grismer & Gorin, 2023

Karunarathna, Suranjan, Ukuwela, Kanishka D. B., De Silva, Anslem, Bauer, Aaron M., Madawala, Majintha, Poyarkov, Nikolay A., Botejue, Madhava, Gabadage, Dinesh, Grismer, L. Lee & Gorin, Vladislav A., 2023, A phylogenetic and taxonomic assessment of the Cnemaspis alwisi group (Reptilia: Gekkonidae) in Sri Lanka with a description of two new species from isolated misty-mountains, Vertebrate Zoology 73, pp. 205-236 : 205

Cnemaspis nanayakkarai sp. nov.

Figs 8 , 9

Holotype.

NMSL.2021.06.01, adult male, 32.6 mmSVL, collected from a large granite cave covered with dence canopy close to a freshwater tank in Galgiriya mountain range, Kurunegala District, North Western Province, Sri Lanka (7.915631N, 80.379361E, WGS1984; elevation 218 m a.s.l., around 11.00 hrs) on 22 December 2019 by Suranjan Karunarathna.

Paratypes (n = 2).

NMSL.2021.06.02, adult male, 31.2 mmSVL and NMSL.2021.06.03, adult female, 30.6 mmSVL, collected from a large granite cave covered with dence canopy cover close to a freshwater tank, Galgiriya mountain range, Kurunegala District, North Western Province, Sri Lanka (7.911525N, 80.382047E, WGS1984; elevation 225 m a.s.l., around 14.00 hrs) on 22 December 2019 by Suranjan Karunarathna.

Diagnosis.

Cnemaspis nanayakkarai sp. nov., can be readily distinguished from its Sri Lankan congeners by a combination of the following morphological and meristic characteristics and also color pattern: maximum SVL 32.6 mm; dorsum with homogeneous, smooth granular scales; 2/2 supranasals, 3 internasals and 1/1 postnasal; 4 enlarged postmentals; postmentals bounded by 6 chin scales; smooth chin and gular scales, granular, juxtaposed (Fig. 8 ); pectoral and abdominal scales smooth and subimbricate; 5 or 6 poorly developed tubercles on posterior flank; 122-131 paravertebral granules linearly arranged; 25-27 belly scales across the venter; precloacal pores absent in males, 7 or 8 femoral pores in males, on each side separated by 20-22 unpored interfemoral scales, 6 or 7 unpored posterior femoral scales; 116-122 ventral scales; 86-99 midbody scales; subcaudals smooth, subhexagonal, enlarged, subequal, forming a regular median row; 7-9 supralabials; 7 or 8 infralabials; 16 or 17 total lamellae on digit IV of manus, and 17 or 18 total lamellae on digit IV of pes. It is also differentiated by its significantly different morphospatial placement in the multivariate analyses.

Comparisons with other Sri Lankan species.

Among species of the Cnemaspis podihuna clade, Cnemaspis nanayakkarai sp. nov. readily differs from C. kandambyi , C. manoae , C. molligodai and C. podihuna by the absence (vs presence) of precloacal pores, and subhexagonal (vs hexagonal) subcaudals; from C. anslemi by the presence of more belly scales (25-27 vs 19-21), more non-pored interfemoral scales (20-22 vs 9 or 10), fewer femoral pores (7 or 8 vs 14 or 15), and fewer lamellae under 4th toe (17 or 18 vs 20 or 21); from C. gemunu by the presence of a greater number of belly scales (25-27 vs 13-16), greater number of paravertebral granules (122-131 vs 79-93), more non-pored interfemoral scales (20-22 vs 10-12), and fewer femoral pores (7 or 8 vs 11-14); from C. godagedarai by the presence of fewer ventral scales (116-122 vs 133-137), more paravertebral granules (122-131 vs 101-106), more non-pored interfemoral scales (20-22 vs 7-9), fewer femoral pores (7 or 8 vs 12 or 13), and fewer lamellae under 4th toe (17 or 18 vs 20 or 21); from C. jayaweerai sp. nov. by the presence of a greater number of midbody scales (86-99 vs 70-77), more non-pored interfemoral scales (20-22 vs 15-17), and fewer femoral pores (7 or 8 vs 10 or 11); from C. phillipsi by the presence of fewer ventral scales (116-122 vs 128-143), more paravertebral granules (122-131 vs 86-93), more non-pored interfemoral scales (20-22 vs 11-14), and fewer femoral pores (7 or 8 vs 15 or 16); from C. scalpensis by the presence of a greater number of belly scales (25-27 vs 17-19), more paravertebral granules (122-131 vs 102-112), more non-pored interfemoral scales (20-22 vs 8-12), fewer flank spines (5 or 6 vs 9-11), and fewer femoral pores (7 or 8 vs 13-15); from C. alwisi by the presence of fewer ventral scales (116-122 vs 145-153), more midbody scales (86-99 vs 71-78), more paravertebral granules (122-131 vs 89-97), and a smaller SVL (32.6 mm vs 40.4 mm); from C. gunasekarai by the presence of a greater number of belly scales (25-27 vs 20-22), more non-pored interfemoral scales (20-22 vs 15-17), and fewer femoral pores (7 or 8 vs 9 or 10); from C. gunawardanai by the presence of fewer ventral scales (116-122 vs 159-162), fewer paravertebral granules (122-131 vs 148-155), fewer lamellae on 4th finger (16 or 17 vs 19-21), and fewer lamellae on 4th toe (17 or 18 vs 21-23); from C. hitihamii by the presence of fewer ventral scales (116-122 vs 132-135), fewer paravertebral granules (122-131 vs 143-149), fewer non-pored interfemoral scales (20-22 vs 24-26), and fewer lamellae on 4th toe (17 or 18 vs 21 or 22); from C. kohukumburai by the presence of fewer ventral scales (116-122 vs 131-134), fewer paravertebral granules (122-131 vs 150-159), fewer lamellae under 4th finger (16 or 17 vs 21 or 22), and fewer lamellae under 4th toe (17 or 18 vs 23-25); from C. nilgala by the presence of a greater number of belly scales (25-27 vs 17-19), more midbody scales (86-99 vs 71-78), fewer paravertebral granules (122-131 vs 179-187), and greater non-pored interfemoral scales (20-22 vs 14 or 15); from C. punctata by the presence of fewer ventral scales (116-122 vs 129-137), more midbody scales (86-99 vs 71-78), more paravertebral granules (122-131 vs 83-91), fewer non-pored interfemoral scales (20-22 vs 25-27), and fewer flank spines (5 or 6 vs 11-13); from C. rajakarunai by the presence of fewer infralabials (7 or 8 vs 9-11), fewer ventral scales (116-122 vs 146-186), more midbody scales (86-99 vs 69-74), and more paravertebral granules (122-131 vs 81-85), from C. rammalensis by the presence of fewer ventral scales (116-122 vs 186-207), fewer midbody scales (86-99 vs 119-131), more paravertebral granules (122-131 vs 94-96), fewer femoral pores (7 or 8 vs 14-16), fewer lamellae under 4th finger (16 or 17 vs 22 or 23), fewer lamellae under 4th toe (17 or 18 vs 22 or 23), and a smaller SVL (32.6 mm vs 53.8 mm) respectively.

Among species of the Cnemaspis kandiana clade, Cnemaspis nanayakkarai sp. nov. differs by the presence (vs absence) of clearly enlarged, subhexagonal subcaudal scales and absence (vs presence) of precloacal pores from the following species: C. amith , C. butewai , C. dissanayakai , C. gotaimbarai , C. ingerorum , C. kallima , C. kandiana , C. kawminiae , C. kivulegedarai , C. kotagamai , C. kumarasinghei , C. latha , C. lokugei , C. menikay , C. nandimithrai , C. pava , C. pulchra , C. retigalensis , C. samanalensis , C. silvula , C. tropidogaster , and C. upendrai .

Description of holotype.

An adult male, 32.6 mmSVL, and 35.7 mmTAL. Body somewhat stout, relatively short (TRL/SVL ratio 39.0%). Head relatively small (HL/SVL ratio 26.1% and HL/TRL ratio 66.9%), very narrow (HW/SVL ratio 14.8% and HW/HL ratio 56.7%), less depressed (HD/SVL ratio 9.5% and HD/HL ratio 36.6%) and distinct from neck. Snout relatively very long (ES/HW ratio 74.0% and ES/HL ratio 41.9%), more than twice the eye diameter (ED/ES ratio 52.8%), more than half length of jaw (ES/JL ratio 62.2%), snout slightly concave in lateral view; eye relatively large (ED/HL ratio 22.1%), less than twice larger than the ear (EL/ED ratio 47.3%), pupil rounded; orbit length greater than eye to ear distance (OD/EE ratio 122.9%) and little longer than digit IV of the manus (OD/DLM IV ratio 103.2%); supraocular ridges not prominent; ear opening relatively large (EL/HL ratio 10.5%), deep, taller than wide, larger than nostrils; 2 rows of scales separate orbit from supralabials; interorbital distance is relatively broad (IO/ES ratio 99.7%), shorter than head length (IO/HL ratio 41.8%); eye to nostril distance greater than the eye to ear distance (EN/EE ratio 122.9%).

Dorsal surface of the trunk with small, smooth, homogeneous granules, 131 paravertebral granules; 122 smooth midventral scales; 88 midbody scales across belly; 6/6 weakly developed, large tubercles on the flanks; ventrolateral scales not enlarged; granules on snout smooth and flat, larger than those on interorbital and occipital regions; canthus rostralis not pronounced, 13/14 smooth oval scales from eye to nostril; scales of the interorbital region round and smooth; ear opening vertically oval, slanting from anterodorsal to posteroventral, 23/21 scales between anterior margin of the ear opening and the posterior margin of the eye. Supralabials 8/9 and infralabials 7/7, becoming smaller towards the gape. Rostral scale longer than wide, partially divided (90%) by a median groove, in contact with first supralabial. Nostrils separated by 2/2 enlarged supranasals with 3 internasal and 1/1 postnasal; no enlarged scales behind the supranasals. Nostrils oval, dorsolaterally orientated, not in contact with first supralabials.

Mental quadtriangular, longer than wide, posteriorly in contact with 4 enlarged postmentals (smaller than mental, and larger than chin scales); postmentals contact and bordered posteriorly by 6 smooth chin scales (larger than nostrils), contact with the 1st infralabials; ventral scales larger than chin scales, and larger than nostrils. Smooth, rounded, juxtaposed granular scales on chin and gular region; pectoral and abdominal scales smooth, subimbricate towards precloacal region, abdominal scales larger than dorsals; 25 belly scales across venter; smooth, subimbricate scales around base of the tail; 8/7 femoral pores; 22 unpored interfemoral scales; 6/6 large posterior femoral scales. Original tail of holotype longer than snout-vent length (TAL/SVL ratio 109.6%), less spine-like tubercles along tail side, homogeneous scales on the dorsal aspect of the tail directed backwards, tail with 2 or 3 enlarged flattened obtuse scales forming whorls; hemipenial bulge greatly swollen (TBW 3.1 mm), a very small, round post-cloacal spur on each side; smooth subcaudals are arranged into a median series of clearly enlarged, subhexagonal scales.

Forelimbs moderately short, slender, upper arm little longer than lower arm (LAL/SVL ratio 13.3% and UAL/SVL ratio 14.5%); hind limbs relatively long, tibia shorter than the femur (TBL/SVL ratio 19.1% and FEL/SVL ratio 22.5%). Anterior, dorsal and posterior surfaces of upper arm and lower arms with somewhat keeled scales, ventral surface smooth, those on ventral surface little large than those on other faces of limb. Scales on anterior and posterior surfaces of the femur and tibia somewhat keeled, scales on the dorsal surface granular, ventral surface smooth, anterior surface is twice the size of those of the other parts. Dorsal and ventral scales on the manus and the pes smooth, granular; dorsal surfaces of digits with granular scales. Digits elongate and slender with inflected distal phalanges, all bearing slightly recurved claws. Subdigital lamellae entire (except divided at first interphalangial joint), unnotched; total lamellae on manus (left/right): digit I (12/11), digit II (14/15), digit III (17/16), digit IV (17/17), digit V (14/13); total lamellae on pes (left/right): digit I (11/12), digit II (15/14), digit III (17/16), digit IV (18/18), digit V (18/17); interdigital webbing absent; length order of digits of left manus: I (1.6 mm), II (1.9 mm), V (2.2 mm), III (2.6 mm), IV (3.1 mm); length order of digits of left pes: I (1.9 mm), II (2.8 mm), V (3.4 mm), III (3.7 mm), IV (4.3 mm).

Variation of the type series.

The SVL of adult specimens in the type series of Cnemaspis nanayakkarai sp. nov. (n = 3) ranges from 30.6 to 32.6 mm; number of supralabials 7-9, and infralabials 7 or 8 (Tables 2 - 4 ); spines on flank 5 or 6; interorbital scales 26-33; supraciliaries 15 or 16; canthal scales 12-14; scales from eye to tympanum 20-23; ventral scales 116-122, midbody scales 86-99; paravertebral granules 122-131; belly scales 25-27. Precloacal pores absent in males, femoral pores in males 7 or 8; unpored interfemoral scales in males 20-22, and unpored posterior femoral scales in males 6 or 7. Total lamellae under digits of the manus: digit I (11 or 12), digit II (14 or 15), digit III (16 or 17), digit IV (16 or 17), digit V (12-14); total lamellae under digits of the pes: digit I (11 or 12), digit II (14 or 15), digit III (16 or 17), digit IV (17 or 18), digit V (17 or 18).

Color of living specimens.

The dorsal color of the head, body and limbs generally grey to brown, with 5-7 paired small black and white paravertebral blotches and 4-6 white crown-like markings along vertebra in both sexes; tail is cinnamon-brown on the dorsum with 12-14 faded cream-white and dark crossbands along its length (Fig. 9 ); a large blackish nuchal dash present on the head, reticulated pattern on the occipital area, snout yellowish; the pupil circular and black with the surrounding scales reddish brown in both sexes; supraciliaries grey; supralabials and infralabials yellowish and dusted with black; a straight, thin and dark postorbital stripe on either side running towards ear; chin and gular region pure white; throat, pectoral, abdomen, cloacal and subcaudal scales are bright-yellow without dark spots; limbs, pale-yellow ventrally, with white dorsal spots and dark irregular bands dorsally in both sexes; manus and pes with irregular black and white crossbands on dorsum.

Color of preserved specimens.

Dorsum faded brown intermixed with pale crown-like markings; paravertebral blotches distinct light-brown and dirty white spots intermixed; reticulated pattern on the occipital clearly distinct in both sexes; limbs with dark and light dorsal spots; dorsal tail is pale-brown with dark cross bands; chin, gular, pectoral, cloacal and subcaudals dirty white with some scales on thigh, tail base and arms with irregular dark-brown margins in both sexes.

Etymology.

The specific epithet ( Cnemaspis nanayakkarai ) is a Latinized eponym in the masculine genitive singular, honouring Mr. Ananda Lal Nanayakkara (a senior member and a senior instructor of the reptile study group of the Young Zoologists’ Association (YZA) of Sri Lanka; reputed lawyer; policy maker, researcher) for his friendship and valuable contribution to reptile conservation in Sri Lanka.

Distribution and natural history.

The type locality, Galgiriya (8.0910 to 8.1514N and 80.6246 to 80.6896E), is an isolated mountain range with granite rock outcrop forests dominated by tall shade-bearing trees (e.g. Hopea brevipetiolaris ), belonging to the dry mixed semi-evergreen forest type ( Gunatileke and Gunatileke 1990). The land area is approximately 1000 ha and situated in the Kurunegala District, North Western Province (dry bioclimatic zone) of Sri Lanka. The mean annual rainfall varies between 1,000 and 1,500 mm, which is received mainly during the northeast monsoon (No-vember-February), but a lesser amount during the southwest monsoon (May-September). The mean annual temperature of the area is 29.2-30.5°C, and its elevational range is 120-550 m a.s.l. Based on our preliminary investigations (22 December 2019, 10 February 2020, and 16 August 2020), Cnemaspis nanayakkarai sp. nov. appeared to be common in Galgiriya forest. Our survey of 12 ha revealed 32 ( ± 0.2) geckos for 24 man-hours. This species was restricted to granite caves (mainly prehistoric granite caves modified 1,000 years ago by natives) in closed canopy forest, and old buildings associated with granite caves within the forest (Fig. 10 ). Furthermore, this species prefers narrow (~7-12 mm), long (~180-450 mm) and deep (~130-210 mm) crevices as hiding places. These microhabitats were poorly illuminated (light intensity: 246-692 Lux), relatively moist (relative humidity: 65-80% and canopy cover: 70-95%) and moderately cool (ambient temperature: 29.5-31.2°C and substrate temperature: 28.2-29.4°C). The new species was sympatric with several other gecko species: Gehyra mutilata , Hemidactylus depressus , H. frenatus , H. parvimaculatus , and H. triedrus . Eggs, hatchlings and juveniles were not observed in the habitat, but gravid females were observed in year 2019 and 2020.

Conservation status.

Application of the IUCN Red List criteria indicates that Cnemaspis nanayakkarai sp. nov. is Critically Endangered (CR) due to having an area of occupancy (AOO) <10 km2 (six locations - single forest block, 0.27 km2 in total assuming a 100 m radius around each georeferenced location) and an extent of occurrence (EOO) <100 km2 (1.45 km2) in the North Western Province [Applicable criteria B2-b (iii)] (Fig. 7 ) of Sri Lanka.

Figures

Figure 7. Currently known distribution of the members of the Cnemaspis alwisi and Cnemaspis rammalensis groups with new species - Cnemaspis jayaweerai sp. nov. and Cnemaspis nanayakkarai sp. nov. with the three major mountain habitats and seven elevational ranges in Sri Lanka (abbreviations: AZ Semi-arid zone, DZ dry zone, IZ intermediate zone, and WZ wet zone; Inset top to bottom: Knuckles mountain massif, Central highlands, and Rakwana mountain massif). Photos: Vimukthi Weeratunga and Ashan Geganage. Map: Buddhika Madurapperuma.

Figure 8. Cnemaspis nanayakkarai sp. nov. male holotype (NMSL. 2021.06.01): A dorsal aspect of head, B lateral aspect of head, C ventral aspect of head, D homogeneous scales on dorsal surface of trunk, E lateral surface of trunk, F smooth ventral scales, G cloacal characters with only femoral pores, H subdigital lamellae of manus, I subdigital lamellae of pes, J dorsal side of tail, K lateral side of tail, L large subhexagonal subcaudals. Scale bar: 2 mm. Photos: Suranjan Karunarathna.

Figure 9. Body coloration of Cnemaspis nanayakkarai sp. nov.: A dorsal view in life in-situ of female paratype (NMSL. 2021.06.03), B ventral aspect of male holotype (NMSL. 2021.06.01) showing gular, ventral, and tail coloration, and C lateral aspect of male holotype in life in-situ with parasites. Photos: Suranjan Karunarathna.

Figure 10. General habitat of Cnemaspis nanayakkarai sp. nov. in Galgiriya, Kurunegala District of Sri Lanka: A an isolated granite mountain ridge with a dense forest, B historic granite cave complex with lots of cracks and holes in a Buddhist monastry, C dense canopy cover with humid conditions inside the forest. Photos: Suranjan Karunarathna.