Cyrtodactylus kulenensis, Grismer & Geissler & Neang & Hartmann & Wagner & Poyarkov, 2021

Grismer, L. Lee, Geissler, Peter, Neang, Thy, Hartmann, Timo, Wagner, Philipp & Poyarkov, Nikolay A., 2021, Molecular phylogenetics, PCA, and MFA recover a new species of Cyrtodactylus (Squamata: Gekkonidae) from an isolated sandstone massif in northwestern Cambodia, Zootaxa 4949 (2), pp. 261-288 : 278-281

Cyrtodactylus kulenensis sp. nov.

Suggested Common Name: Phnom Kulen Bent-toed Gecko

( Fig. 7 )

Cyrtodactylus cf. intermedius . Geissler et al. 2019:49.

Holotype. Adult male ZFMK 92573 from Phnom Kulen National Park , Phnom Kbal, Banteay Srei District, Siem Reap Province, Cambodia (13°41’21’’N, 104°00’55’’E °N at about 490 m in elevation) collected by TH and PG on 2 June 2011.

Paratypes. Adult females ZFMK 88356 , ZFMK 88357 , ZFMK 88359 and subadult male ZFMK 88358 collected by TH in September 2008. Adult female CBC (Centre for Biological Conservation) 03030 and juvenile ZFMK 90311 collected by TH in June 2009. Adult females ZFMK 92572 , ZFMK 92574 , ZFMK 92575 collected by TH and PG in June 2011. All paratypes were collected on Phnom Kbal Spean , Phnom Kulen National Park , Phnom Kbal, Banteay Srei District, Siem Reap Province, Cambodia (13°41’21’’N, 104°00’55’’E °N between 480 and 496 m in elevation) .

Diagnosis. Cyrtodactylus kulenensis sp. nov. can be separated from all other species of the C. intermedius group by having 8–11 supralabials, 8–11 infralabials, 33–38 paravertebral tubercles, 17–19 rows of longitudinally arranged tubercles, 38–44 ventrals, seven or eight expanded subdigital lamellae on the fourth toe, 11–13 unexpanded subdigital lamellae on the fourth toe, 18–21 total subdigital lamellae on the fourth toe, 12–21 enlarged femorals, nine or 10 enlarged precloacals, two or three rows of enlarged post-precloacals, two or three postcloacal tubercles, nine or 10 precloacal pores in males (N=2), enlarged femorals and enlarged precloacals continuous, proximal femorals less than one-half the size of the distal femorals, no digital pockets, maximum SVL 89.6 mm, no large dark blotches on top of head, three or four well-defined brown body bands edged with white tubercles, and body bands narrower than the beige interspaces ( Tables 1, 4).

Description of holotype ( Fig. 7 ). Adult male SVL 87.7 mm; head moderate in length (HL/SVL 0.28), width (HW/HL 0.67), somewhat flattened (HD/HL 0.36), distinct from neck, triangular in dorsal profile; lores concave slightly anteriorly, weakly inflated posteriorly; prefrontal region concave; canthus rostralis rounded; snout elongate (ES/HL 0.37), rounded in dorsal profile; eye large (ED/HL 0.30); ear opening elliptical, obliquely oriented, moderate in size; eye to ear distance slightly greater than diameter of eye; rostral rectangular, partially divided dorsally by inverted Y-shaped 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 smaller postnasals, bordered ventrally by first supralabial; 11,10(R,L) rectangular supralabials extending to below midpoint of eye, second supralabial slightly larger than first; 11,10(R,L) infralabials tapering smoothly to just below and slightly past posterior margin of eye; scales of rostrum and lores flat to domed, larger than granular scales on top of head and occiput; scales of occiput intermixed with distinct, small tubercles; superciliaries elongate, largest anteriorly; mental triangular, bordered laterally by first infralabials and posteriorly by large left and right trapezoidal postmentals contacting medially for 40% of their length posterior to mental; one row of slightly enlarged, elongate sublabials extending posteriorly to fourth infralabial; gular and throat scales small, granular, grading posteriorly into slightly larger, flatter, smooth, imbricate, pectoral and ventral scales.

Body relatively short (AG/SVL 0.44) with well-defined ventrolateral folds; dorsal scales small, granular interspersed with larger, conical, semi-regularly arranged, moderately keeled tubercles; tubercles extend from top of head onto base of tail forming transverse rows, terminating at regenerated portion of tail; smaller tubercles extend anteriorly onto nape and occiput, diminishing in size and distinction on top of head; approximately 19 longitudinal rows of tubercles at midbody; approximately 38 paravertebral tubercles; 39 flat, imbricate, ventral scales much larger than dorsal scales; 10 large, pore-bearing, precloacal scales; no deep precloacal groove or depression; and three rows of large post-precloacal scales on midline.

Forelimbs moderate in stature, relatively short (FL/SVL 0.14); granular scales of forearm slightly larger than those on body, interspersed with small tubercles; palmar scales rounded, slightly raised; interdigital pocketing absent; digits well-developed, 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; 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 9,10(R,L) enlarged femoral scales not continuous with enlarged precloacal scales, terminating distally before knee; proximal femoral scales smaller than distal femorals, the latter forming an abrupt union with smaller, rounded, ventral scales of posteroventral margin of thigh; femoral pores absent; plantar scales flat; interdigital pocketing absent; digits relatively long, well-developed, inflected at basal interphalangeal joints; 8(R,L) wide, transversely expanded subdigital lamellae on fourth toe proximal to joint inflection that extend onto sole; 12,12(R,L) narrower, transverse lamellae distal to inflection; 20 total subdigital lamellae; and claws welldeveloped, sheathed by a dorsal and ventral scale at base.

Tail 108.4 mm in length, first 8.1 mm original, 6.2 mm in width at base, tapering to a point; dorsal scales of original portion, flat, square; regenerated portion covered with small, smooth subcircular scales; median row of transversely expanded subcaudal scales, significantly larger than dorsal caudal scales on original portion; base of tail bearing hemipenal swellings; three conical postcloacal tubercles at base of hemipenal swellings; and postcloacal scales flat, imbricate.

Coloration in preservation ( Fig. 7 ). Ground color of top of head, limbs, and dorsum brown, immaculate; wide dark-brown nuchal loop edged with white tubercles extends from posterior margin of one orbit across nape to posterior margin of opposing orbit; four dark-brown, straight-edged, bands bordered with white tubercles and slightly wider beige interspaces extend from forelimb insertion to groin, no caudal bands on unicolor brown, regenerated tail; and ventral surfaces of gular region, limbs and body dull-white to beige, bearing fine, dark, stippling.

Variation. The paratypes generally resemble the coloration and pattern of the holotype with the exception of ZMFK 88358 in which the first band is divided into three, oval-shaped parts, and the second band is nearly divided on the midline of the body and in ZMFK 88356 , where the first band is divided on the midline ( Fig. 8 ). With the exception of ZMFK 88356–57 , the dark caudal bands are wider than the light caudal bands and encircle the tail. Meristic variation is provided in Table 4. Coloration in life is illustrated in Figure 8 .

Distribution. Cyrtodactylus kulenensis sp. nov. is known only from the type locality in the Phnom Kulen National Park, Banteay Srei District, Siem Reap Province, Cambodia ( Fig. 1 ).

Etymology. The specific epithet kulenensis is a Latinized toponymic adjective named after Phnom (=Mount) Kulen National Park, Banteay Srei District, Siem Reap Province, Cambodia. “Phnom Kulen” means “the Mountain of Lychees” in Khmer language.

Comparisons. Cyrtodactylus kulenensis sp. nov. is most closely related to Cyrtodactylus sp. 2 but is differentiated from it by having a significantly higher mean number of supralabial scales (SL), paravertebral tubercles (PVT), enlarged femoral scales (FS), and enlarged precloacal scales (PS). It is differentiated from C. intermedius s.s. by having continuous as opposed to discontinuous enlarged femoral and precloacal scales ( Smith 1917). It can be further differentiated from all other members of the C. intermedius group by having a significantly greater mean number of supralabials and paravertebral tubercles. It differs further from C. auralensis , C. bokorensis , C. cardamomensis , C. phuquocensis , C. thylcodactylus , and C. septimontium by having a higher mean number of proximal expanded subdigital lamellae (TLE) and is further differentiated from C. bokorensis , C. laagensis , C. kohrongensis , C. phuquocensis , and C. septimontium in having a higher mean number of enlarged precloacal scales. Other differences between C. kulenensis sp. nov. and various combinations of species are illustrated in Figure 5 and listed Table 1. Cyrtodactylus kulenensis sp. nov. is well-separated from all other species in all three multivariate analyses ( Figs. 4 and 6 ). Additionally, C. kulenensis sp. nov. differs from its sister species Cyrtodactylus sp. 2 by an uncorrected pairwise sequence divergence of 4.4%. It is likely this percentage would be much different using a full read of ND2 and its flanking tRNAs.

Natural history. The Phnom Kulen National Park encompasses a small (374 km 2), forested, hilly, habitat-island in the Phnom Kulen mountain massif surrounded by the lowlands of northern Cambodia in the Tonle Sap Basin. The massif reaches 500 m in elevation and supports semi-evergreen forest on the hillsides and upper elevations and degraded dry deciduous dipterocarp forest at lower elevations. According to Geissler et al. (2019), all specimens were collected from 17:30–23:00 hrs in the month of June and September hiding in rock crevices or while foraging on sandstone rocks in semi-evergreen forest ( Fig. 9 ).

Figures

FIGURE 1. Distribution of the species of the Cyrtodactylus intermedius group.

FIGURE 4. A. PCA of the species the Cyrtodactylus intermedius group based on meristic characters. Plot points with white borders are centroids. B. DAPC of same. C. Histograms of the factor loadings of the characters contributing most to the variation along PC1, PC2, PC3, and PC4. Abbreviations are in the materials and methods.

FIGURE 5. Boxplot comparisons of meristic characters among the species of the Cyrtodactylus intermedius group. Light-blue circles are means and the black horizontal bars are medians. Asterisks denote species bearing statistically significant mean differences from C. kulenensis sp. nov.

FIGURE 6. MFA scatter plot showing the morphospatial relationships among the species of the Cyrtodactylus intermedius group and bar graphs showing the percent contribution of each data type to the overall variation in the data set. The dashed red line in the bar graphs indicates the expected average value if the contributions of each data type were equal.

FIGURE 7. Holotype of adult male Cyrtodactylus kulenensis sp. nov. (ZFMK 92573. A. Dorsal view. B. Ventral view of femoral and precloacal regions. C. Ventral view of left foot. D. Lateral view of head. E. Dorsal view of head. F. Ventral view of gular region.

FIGURE 8. In situ view of Cyrtodactlus kulenensis sp. nov. A. ZFMK 92575 adult female. B. ZFMK 92572 adult female. C. ZFMK 88357 adult female. D. ZFMK 88358 subadult male.

FIGURE 9. Habitat of Cyrtodactylus kulenensis sp. nov. at Phnom Kulen National Park, Phnom Kbal Spean, Banteay Srei District, Siem Reap Province, Cambodia.