Cyrtodactylus bokorensis, Murdoch & Grismer & Wood Jr & Neang & Poyarkov & Tri & Nazarov & Aowphol & Pauwels & Nguyen & Grismer, 2019

Murdoch, Matthew L., Grismer, L. Lee, Wood Jr, Perry L., Neang, Thy, Poyarkov, Nikolay A., Tri, Ngo Van, Nazarov, Roman A., Aowphol, Anchalee, Pauwels, Olivier S. G., Nguyen, Hung Ngoc & Grismer, Jesse L., 2019, Six new species of the Cyrtodactylus intermedius complex (Squamata: Gekkonidae) from the Cardamom Mountains and associated highlands of Southeast Asia, Zootaxa 4554 (1), pp. 1-62 : 27-32

Cyrtodactylus bokorensis sp. nov.

Bokor Plateau Bent-toed Gecko

Figs. 12 & 13 , Table 10.

Gymnodactylus intermedius Smith 1935:44 .

Cyrtodactylus intermedius Stuart & Emmett 2006:17 .

Holotype. Adult male LSUHC 8554 collected on 10 July 2007 by L. Lee Grismer and Neang Thy from the Bokor National Park Field Station , Kampot Province, Cambodia (10 37.611' N 104 01.541' E; 1033 m in elevation).

Paratypes. Adult males LSUHC 8541–42 , adult females LSUHC 8548–50 and 8555 bear the same collection data as the holotype .

Diagnosis. Adult males reaching 81.9 mm SVL, adult females reaching 93 mm SVL; eight supralabials, 8–10 infralabials; 30–33 paravertebral tubercles; 18–20 longitudinal rows of dorsal tubercles; 42–48 rows of ventral scales; six or seven expanded subdigital lamellae proximal to the digital inflection, 11–14 unmodified, distal, subdigital lamellae; 18–20 total subdigital lamellae on fourth toe; enlarged femoral and precloacal scales vary from being separated by a diastema to continuous; 26–30 enlarged femoral scales; proximal femoral scales less than half the size of distal proximal scales; 7–10 enlarged precloacal scales with pores on each in males; two or three rows of enlarged post-precloacal scales; two or three postcloacal tubercles; no pocketing present between digits of hind or forefeet; dark pigmented blotches on top of head vary from present to absent; posterior border of nuchal loop pointed, chevron-shaped; and four or five dark body bands ( Table 10). These characters are scored across all species of the Cyrtodactylus intermedius complex in Table 7.

Description of holotype. Adult male SVL 81.9 mm; head moderate in length (HL/SVL 0.28) and width (HW/ HL 0.65), somewhat flattened (HD/HL 0.36), distinct from neck, and triangular in dorsal profile; lores concave anteriorly, weakly inflated posteriorly, prefrontal region moderately concave, canthus rostralis rounded; snout elongate (ES/HL 0.39), rounded in dorsal profile; eye large (ED/HL 0.23); ear opening elliptical, obliquely oriented, moderate in size (EL/HL 0.08); eye to ear distance greater than diameter of eye; rostral rectangular, partially divided dorsally by a linear furrow, bordered posteriorly by large left and right supranasals and single moderately sized internasal, bordered laterally by first supralabials; external nares bordered anteriorly by rostral, dorsally by large supranasal, posteriorly by three moderately sized postnasals, bordered ventrally by first supralabial; 8(R,L) rectangular supralabials extending to below midpoint of eye, second supralabial slightly larger than first; 9(R,L) infralabials tapering smoothly to below and slightly past the termination of enlarged supralabials; scales of rostrum and lores flat to slightly raised, larger than granular scales on top of head and occiput; scales of occiput intermixed with distinct, enlarged tubercles; dorsal superciliaries not elongate or keeled; mental triangular, bordered laterally by first infralabials and posteriorly by large left and right trapezoidal postmentals which contact medially for 50% of their length posterior to mental; one row of slightly enlarged, elongate sublabials extending posteriorly to seventh infralabial; gular and throat scales small, granular, grading posteriorly into slightly larger, flatter, smooth, imbricate, pectoral and ventral scales.

and Methods. R = right, L = left, / = data unobtainable, r = regenerated, b = broken.

Body relatively short (AG/SVL 0.47) with poorly defined ventrolateral folds; dorsal scales small, granular interspersed with relatively large, conical, semi-regularly arranged, weakly keeled tubercles; tubercles extend from occiput to caudal constriction and onto tail where they occur in transverse rows separated by six small flat scales; caudal tubercles largest dorsally, weak laterally, and absent ventrally; similarly sized and spaced tubercles continue onto occiput and nape of the neck but diminish in size and distinction on top of the head; approximately 20 longitudinal rows of tubercles at midbody between ventrolateral, body folds; 33 paravertebral tubercles; 42 flat, imbricate, ventral scales between ventrolateral body folds, ventral scales much larger than dorsal scales; nine large, pore-bearing, precloacal scales; no deep precloacal groove or depression; and three rows of post-precloacal scales.

Forelimbs moderate in stature, relatively short (FL/SVL 0.15); granular scales of forearm larger than those on body, interspersed with large, conical tubercles; palmar scales rounded, slightly raised; interdigital pocketing absent on the forefeet; digits well-developed, inflected at basal, interphalangeal joints; digits slightly more narrow distal to inflections; subdigital lamellae transversely expanded proximal to joint inflections, more granular distal to inflection; claws well-developed, claw base sheathed by a dorsal and ventral scale; hind limbs more robust than forelimbs, moderate in length (TBL/SVL 0.18), covered dorsally by granular scales interspersed with large, conical tubercles and anteriorly by flat, slightly larger scales; ventral scales of thigh flat, imbricate, larger than dorsals; subtibial scales flat, imbricate; one row of 14(R), 13(L) enlarged femoral scales in contact with enlarged precloacal scales, terminate just medial to inflection of knee; femoral pores absent; proximal femoral scales one-fourth the size of those distal, form abrupt union with smaller, rounded, ventral scales of posteroventral margin of thigh; plantar scales flat; interdigital pocketing absent on hind feet; digits relatively long, well-developed, inflected at basal, interphalangeal joints; 6(R,L) transversely expanded subdigital lamellae on fourth toe proximal to joint inflection that extend onto the sole, 12(R,L) unmodified lamellae distal to inflection; and claws well-developed, sheathed by a dorsal and ventral scale at base.

Tail original, 119 mm in length, 8.1 mm in width at base, tapering to a point; dorsal scales small, square, in transverse rows; tail segmented with five transverse scale rows per segment; posterior margin of segments bordered by four large, keeled tubercles dorsally extending to anterior two-thirds of tail; subcaudal region bearing large, transverse scales for first half of tail, second half bearing smaller, irregularly shaped scales; base of tail bearing hemipenal swellings; three postcloacal tubercles on either side of hemipenal swellings; and postcloacal scales smooth, flat, large, imbricate.

Coloration in alcohol. Dorsal ground color of head, body, limbs and tail dark-brown; dark-brown blotches on top of head ringed with white tubercles; dark-brown nuchal loop with pointed chevron-shaped posterior border extending from posterior margin of one eye to posterior margin of other eye; nuchal loop edged with thin, white, lines; four similarly colored dorsal bands with slightly lightened centers occur between limb insertions; first band terminates at shoulders; second and third bands bear notches on their anterior borders, terminate dorsal to ventrolateral fold; fourth band terminates at anterior margin of hind limb insertions; light edging on body bands generally restricted to tubercles giving edging a spotted appearance; body band/interspace ratio 1.00; additional dark-brown band posterior to hind limbs; 13 dark, caudal bands; and 12 light caudal bands infused with dark pigment ( Fig 11 ).

Variation. The paratypes closely approach the holotype in coloration ( Fig 11 ). LSUHC 8548 has five bands instead of four. All paratypes have a pointed posterior border of the nuchal loop but vary between sharply and bluntly pointed. All paratypes lack pigmented blotches on the top of their heads. Living specimens have light edging along the dark dorsal bands and the tubercles are white. Tubercles border the dark dorsal bands and the dorsal margin of the high is white. Dark blotches occur on the dorsal margin of the thigh ( Fig 12 ). Meristic differences among the type specimens and additional specimens examined are presented in Table 10.

Additional specimens examined. Seven additional specimens from the type locality were examined ( Table 10).

Distribution. Cyrtodactylus bokorensis sp. nov. is known only from Bokor National park, Kampot province, Cambodia.

Natural history. The type locality is located at 1033 m in elevation near the center of the Bokor Plateau in a wide, open area among low hills. Summit habitat of the plateau is composed of scattered sandstone rocks and boulders among highly disturbed wind-blown scrub vegetation. Also abundant at 350 m elevation in wet evergreen forest associated with rocky areas on the southern side of Bokor NP and therefore probably common throughout the park ( Fig. 12 ). All specimens were collected at night during light intermittent rain showers in the vicinity of the Bokor National Park Field Station. Lizards were found moving across the ground in the open, on the sides of boulders, and on rock walls associated with the field station. Stuart & Emmet (2006) noted that some specimens were collected on vertical walls of a reservoir and one was collected on a piece of sandstone in grassland.

Etymology. The specific epithet, bokorensis sp. nov., is an adjective in reference to type locality of the Bokor Plateau to which it is presumably endemic.

Comparisons. Cyrtodactylus bokorensis sp. nov. is a member of the eastern group and the sister species of Cyrtodactylus laangensis sp. nov. from Phnom Laang from which it is separated by 3.9% sequence divergence ( Table 4). The PCA analysis indicates Cyrtodactylus bokorensis sp. nov. is distinct in morphospace from all other species with the exceptions of C. septimontium sp. nov. and C. cardamomensis sp. nov. with which there is overlap ( Fig 6 ). The concatenated DAPC analysis Cyrtodactylus bokorensis sp. nov. shows complete separation from all other species ( Fig. 7 ). Cyrtodactylus bokorensis sp. nov. is well-differentiated from all other members of the C. intermedius complex by having varying combinations of statistically different mean values of supralabial and infralabial scales, paravertebral tubercles, longitudinal rows of tubercles, ventral scales, unmodified, expanded, and total number of subdigital lamellae, enlarged femoral scales, precloacal scales, and postcloacal tubercles ( Table 6). It differs further from all other members of the complex in the posterior border of the nuchal loop being chevron shaped and relatively pointed as opposed to rounded. It is differentiated from C. thylacodactylus sp. nov. in lacking interdigital pocketing ( Table 7).

Figures

FIGURE 6. Principal component analysis (PCA) of the species of the Cyrtodactylus intermedius complex showing ordination along the first two principal components.

FIGURE 7. Discriminant analysis of principal components (DAPC) of the species of the Cyrtodactylus intermedius complex emphasizing between-group variance and minimizing within-group variance based on retention of the first eight components. Circles represent 95% confidence intervals.

FIGURE 11. Cyrtodactylus auralensis sp. nov. Upper left: LSUDPC 1180; adult female. Upper right: forested microhabitat from the slopes of Phnom Aural at camp II. Lower right: forested microhabitat from the slopes of Phnom Aural at camp I. Bottom right: LSUDPC 1178 hatchling. All photos by L. Grismer.

FIGURE 12. Type series and additional specimens examined of Cyrtodactylus bokorensis sp. nov. Upper: Type series from left to right: holotype LSUHC 8554, paratypes LSUHC 8541-42, 8548-50, 8555. Lower: additional specimens examined.

FIGURE 13. Cyrtodactylus bokorensis sp. nov. Upper left: adult male (photo by Neang Thy). Upper right: wind-swept grassy microhabitat from the top of the Bokor Plateau (photo by L. Grismer). Lower left: Granite boulder strewn stream bed microhabitat from the Bokor Plateau (photo by L. Grismer). Lower right: adult male (photo by Neang Thy).