Cyrtodactylus thongphaphumensis, Grismer & Rujirawan & Chomdej & Suwannapoom & Yodthong & Aksornneam & Aowphol, 2023

Grismer, L. Lee, Rujirawan, Attapol, Chomdej, Siriwadee, Suwannapoom, Chatmongkon, Yodthong, Siriporn, Aksornneam, Akrachai & Aowphol, Anchalee, 2023, A new species of the Cyrtodactylus brevipalmatus group (Squamata, Gekkonidae) from the uplands of western Thailand, ZooKeys 1141, pp. 93-118 : 93

Cyrtodactylus thongphaphumensis sp. nov.

Suggested Common Name: Thong Pha Phum Bent-toed Gecko Figs 4 , 5

Cyrtodactylus sp. 9 Chomdej et al. 2021: 2; Grismer et al. 2022b: 248; Grismer et al. 2022c: 115.

Type material.

Holotype. Adult male ZMKU R 00953 from Thong Pha Phum National Park, Pilok Subdistrict, Thong Pha Phum District, Kanchanaburi Province, Thailand (14.69339°N, 98.40534°E, 914 m a.s.l.), collected by Korkhwan Termprayoon, Akrachai Aksornneam, Natee Ampai, and Siriporn Yodthong on 8 April 2019.

Paratypes. Adult males ZMKU R 00951, ZMKU R 00954 and ZMKU R 00956 and adult females ZMKU R 00950, ZMKU R 00952, ZMKU R 00955, and ZMKU R 00957 bear the same collection data as the holotype.

Diagnosis.

Cyrtodactylus thongphaphumensis sp. nov. can be separated from all other species of the Cyrtodactylus brevipalmatus group by the combination of having 12-14 supralabials, 8-10 infralabials, 30-36 paravertebral tubercles, 19-21 rows of longitudinally arranged tubercles, 30-34 longitudinal rows of ventrals, 150-173 transverse rows of ventrals, 8-10 expanded subdigital lamellae on the fourth toe, 11-14 unexpanded subdigital lamellae on the fourth toe, 20-24 total subdigital lamellae on the fourth toe; seven or eight expanded subdigital lamellae on the fourth finger, 10-12 unexpanded subdigital lamellae on the fourth finger, 18-20 total subdigital lamellae on the fourth finger; 12-16 total number of enlarged femoral scales, 12-16 total number of femoral pores in males; 15 precloacal pores in males; 15-17 enlarged precloacals; enlarged femorals and enlarged precloacals not continuous; proximal femorals smaller than distal femorals; small tubercles on forelimbs and flanks; large dorsolateral caudal tubercles and wide ventrolateral caudal fringe; ventrolateral caudal fringe composed scales of different size; tail square in cross-section; maximum SVL 76.6 mm; 3-5 dark transverse body bands (Table 5 ).

Description of holotype

(Fig. 4 ). Adult male SVL 73.2 mm; head moderate in length (HL/SVL 0.27), width (HW/HL 0.70), depth (HD/HL 0.39), distinct from neck, triangular in dorsal profile; lores concave slightly anteriorly, weakly inflated posteriorly; prefrontal region concave; canthus rostralis rounded; snout elongate (ES/HL 0.40), rounded in dorsal profile; eye large (ED/HL 0.25); ear opening horizontally elliptical, small; eye to ear distance greater than diameter of eye; rostral rectangular, divided by a dorsal furrow, bordered posteriorly by large left and right supranasals and one small azygous internasal, bordered laterally by first supralabials; external nares bordered anteriorly by rostral, dorsally by large supranasal, posteriorly by two unequally sized smaller postnasals, bordered ventrally by first supralabial; 14R/14L rectangular supralabials, second through eighth supralabials nearly same size as first, then tapering below eye; 10R/10L infralabials tapering smoothly to just below and slightly past posterior margin of eye; scales of rostrum and lores flat to slightly domed, larger than granular scales on top of head and occiput; scales of occiput intermixed with distinct, small tubercles; superciliaries subrectangular, largest anterodorsally; mental triangular, bordered laterally by first infralabials and posteriorly by large left and right trapezoidal postmentals contacting medially for 45% of their length posterior to mental; one row of enlarged, square to rectangular sublabials extending posteriorly to sixth(L) and fifth(R) infralabial; gular and throat scales small, granular, grading posteriorly into slightly larger, flatter, smooth, imbricate, pectoral and ventral scales.

Body relatively short (AG/SVL 0.46) with well-defined ventrolateral folds; dorsal scales small, granular interspersed with larger, conical, semi-regularly arranged, weakly keeled tubercles; tubercles extend from occipital region onto base of tail and slightly beyond as paravertebral rows; smaller tubercles extend anteriorly onto nape and occiput, diminishing in size anteriorly; approximately 20 longitudinal rows of tubercles at midbody; approximately 34 paravertebral tubercles; tubercles on flanks; 34 longitudinal rows of flat, imbricate, ventral scales much larger than dorsal scales; 166 transverse rows of ventral scales; 15 large, pore-bearing, precloacal scales; no deep precloacal groove or depression; and two rows of enlarged post-precloacal scales on midline.

Forelimbs moderate in stature, relatively short (ForL/SVL 0.13); granular scales of forearm larger than those on body, interspersed with large flat tubercles; palmar scales rounded, slightly raised; digits well-developed, relatively short, inflected at basal interphalangeal joints; digits narrower distal to inflections; subdigital lamellae wide, transversely expanded proximal to joint inflections, narrower transverse lamellae distal to joint inflections; claws well-developed, claw base sheathed by a dorsal and ventral scale; 8R/8L expanded and 11R/11L unexpanded lamellae beneath the fourth finger; hind limbs larger and thicker than forelimbs, moderate in length (TibL/SVL 0.14), covered dorsally by granular scales interspersed with moderately sized, conical tubercles dorsally and posteriorly and anteriorly by flat, slightly larger, subimbricate scales; ventral scales of thigh flat, imbricate, larger than dorsals; subtibial scales flat, imbricate; one row of 6R/8L enlarged pore-bearing femoral scales not continuous with enlarged pore-bearing precloacal scales, terminating distally at knee; 7R/8L enlarged femoral scales; proximal femoral scales smaller than distal femorals, the former forming an abrupt union with much smaller, rounded, ventral scales of posteroventral margin of thigh; plantar scales flat, subimbricate; digits relatively long, well-developed, inflected at basal interphalangeal joints; 8R/8L wide, transversely expanded subdigital lamellae on fourth toe proximal to joint inflection extending onto sole, and 12R/12L unexpanded lamellae beneath the fourth toe distal to joint inflection; and claws well-developed, claw base sheathed by a dorsal and ventral scale.

Tail original, 94.6 mm long (TL/SVL 1.29), 5.0 mm in width at base, tapering to a point; nearly square in cross-section; dorsal scales flat, intermixed with tubercles forming paravertebral rows anteriorly and larger tubercles forming dorsolateral longitudinal rows; large, posteriorly directed, semi-spinose tubercles forming wide ventrolateral caudal fringe; larger scales of ventrolateral fringe occur at regular intervals; medial subcaudals enlarged but not paired, an enlarged single medial subcaudal longitudinal row absent; subcaudals, larger than dorsal caudals; base of tail bearing hemipenal swellings; 3R/3L conical postcloacal tubercles at base of hemipenal swellings; and postcloacal scales flat, imbricate.

Coloration in life

(Fig. 4 ). Ground color of the head body, limbs, and tail dull yellow; diffuse darker mottling on the top of the head; wider, pale-brown pre- and postorbital stripe extends from external nares to angle of jaw; whitish canthal and postorbital stripe dorsal to pale-brown pre- and postorbital stripe; faint, pale brown, nuchal band bearing two posteriorly directed projections; paired dark-brown paravertebral blotches on nape; four wide, irregularly shaped and broken transverse body bands edged in slightly pale brown between limb insertions; band interspaces bearing irregularly shaped scattered pale-brown markings; very faint pale-brown speckling on limbs and digits; seven wide pale-brown caudal bands separated by seven paler colored bands; posterior five pale-brown caudal bands encircle tail; ventral surfaces of body and limbs beige, generally immaculate, subcaudal region generally darker; iris orange-gold in color bearing black vermiculations.

Variation

(Fig. 5 , Table 5 ). Individuals of the type series are very similar in overall coloration and pattern. TL and TW of complete original tails (ZMKU R 00951-00952, ZMKU R 00954, ZMKU R 00957) are 80.1-94.7 mm (mean 89.1 ± 6.5 mm; N = 4) and 4.2-4.9 mm (mean 4.7 ± 0.3; N = 4), respectively. ZMKU R 00956 has a short, partially regenerated tail which lacks banding (TL 27.7 mm, TW 5.1 mm). Similarly, the posterior sections of the tails in ZMKU R 00950 (TL 75.5 mm, TW 5.0 mm) and ZMKU R 00955 (TL 73.3 mm, TW 4.7 mm) are regenerated. Specimens ZMKU R 00950, ZMKU R 00952, and ZMKU R 00954 have three as opposed to four body bands in the holotype and ZMKU R 00955 has five body bands. Raw morphometric and meristic differences within and among all species of the Cyrtodactylus brevipalmatus group are listed in Table 5 .

Distribution.

Cyrtodactylus thongphaphumensis sp. nov. is currently known only from the type locality at Thong Pha Phum National Park, Pilok Subdistrict, Thong Pha Phum District, Kanchanaburi Province, Thailand (Fig. 1 ).

Etymology.

The specific epithet Cyrtodactylus thongphaphumensis is in reference to the type locality of Thong Pha Phum National Park.

Comparisons.

Cyrtodactylus thongphaphumensis sp. nov. is the sister species to a clade composed of eight lineages in the phylogenetic sequence of C. uthaiensis , sp. 11, C. interdigitalis , C. cf. ngati 1, C. cf. ngati 2, C. ngati 3, and the sister lineages C. ngati 4 and C. ngati (Fig. 2 ). Cyrtodactylus thongphaphumensis sp. nov. differs from those lineages by an uncorrected pairwise sequence divergence of 7.6-9.7% and from all members of the Cyrtodactylus brevipalmatus group by 7.6-22.3% (Table 2 ). It differs discretely from C. elok by having as opposed to lacking paravertebral tubercles, femoral and precloacal pores, and by having 19-21 as opposed to 4-7 longitudinal rows of tubercles. It differs from C. brevipalmatus , C. fluvicavus , C. interdigitalis , C. ngati , C. ngati 3, and C. rukhadeva in having statistically significant different mean values of combinations of the morphometric characters of AG, HumL, ForL, TibL, HL, HW, HD, EE, ES, EN, EL, and IN (Table 3 ). It differs further from those same species in having statistically significant different mean values of combinations of the meristic characters SL, PVT, LRT, VS, VSM, TL4T, FL4E, FL4U, FL4T, FS, PCS, and BB (Table 3 ). Discrete differences between Cyrtodactylus thongphaphumensis sp. nov. and other putative species and populations are presented in Table 5 .

Natural history.

All individuals were found in hill evergreen forest at 914 m elevation (Fig. 6 ). Specimens (N = 8) were collected at night (1900-2100 h) during the dry season (April) on tree trunks (62.5%; N = 5), on a building (12.5%; N = 1), and the ground (25.0%; N = 2) with a temperature of 27.0 °C and relative humidity of 71.1%. The holotype (ZMKU R 00953) and four paratypes (ZMKU R 00950, ZMKU R 00954, ZMKU R 00956-00957) were found on tree trunks ≤ 160 cm above ground level. One specimen (ZMKU R 00951) was found on a building. Two specimens (ZMKU R 00952, ZMKU R 00955) were found on ground. At night, the new species was found to co-occur with other gekkonid lizards, Cyrtodactylus oldhami (Theobald, 1876), Gekko kaengkrachanense (Sumontha, Pauwels, Kunya, Limlikhitaksorn, Ruksue, Taokratok, Ansermet & Chanhome, 2012), and Hemidactylus garnotii Duméril & Bibron, 1836.

Figures

Figure 1. Distribution of nominal species and unnamed populations of the Cyrtodactylus brevipalmatus group. Stars denote type localities. White circles are literature localities from which specimens were not examined and remain unidentified. Locality data for all material examined is in Grismer et al. (2022 c: table 1).

Figure 2. Maximum clade credibility BEAST phylogeny of the Cyrtodactylus brevipalmatus group highlighting the new species described herein. Bayesian posterior probabilities (BPP) are listed at the nodes.

Figure 4. Adult male holotype of Cyrtodactylus thongphaphumensis sp. nov. ZMKU R 00953 (field no. AA 06933) from Thong Pha Phum National Park, Pilok Subdistrict, Thong Pha Phum District, Kanchanaburi Province, Thailand. A dorsal view B ventral view C dorsal view of head and ventral view of pelvic region D dorsal view of tail and E ventral view of tail in preservative F holotype in life.

Figure 5. Paratypes of Cyrtodactylus thongphaphumensis sp. nov. in preservative from Thong Pha Phum National Park, Pilok Subdistrict, Thong Pha Phum District, Kanchanaburi Province, Thailand.

Figure 6. Habitat of the type locality at Thong Pha Phum National Park, Pilok Subdistrict, Thong Pha Phum District, Kanchanaburi Province, Thailand.