Cyrtodactylus septimontium, 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 : 46-54

Cyrtodactylus septimontium sp. nov.

Bảy Núi (Seven Mountains) Bent-toed Gecko

Figs. 20 & 21 , Table 14.

Cyrtodactylus intermedius Ngo and Grismer 2006: 328 ; Bobrov & Semenov 2008: 236; Nguyen, Ho, & Nguyen 2009: 768; Nguyen et al. 2013; Nguyen et al. 2014.

Holotype. Adult male LSUHC 12484 collected on 5 December 2005 by Ngo Van Tri at Nui Cam Mountain , An Giang province, Vietnam.

Paratypes. Adult male LSUHC 8244 and adult female 8243 bear the same collection data as holotype. Adult female LSUHC 12485 was collected at the same location. Adult male LSUHC 12488 and adult females LSUHC 12486–87 were collected on the adjacent hill Ta Soc Mountain , An Giang province, Vietnam. Adult males NAP– 0 5274, 0 5277, and adult females NAP–05272–73, 05275–76, all registered as ZMMU R–14773, were collected at Nui Cam mountain , An Giang Province, Vietnam, on 26 August 2015 by N.A. Poyarkov and Nguyen Ngoc Hung (N 10.51169; E 104.97193; 436 meters in elevation). Adult males NAP–05320–21, 0 5323, 0 5325, and adult females NAP–05322, 0 5324, all registered as ZMMU R–14775, were collected at Nui Co To mountain, An Giang Province, Vietnam, on 25 August 2015 by N.A. Poyarkov and Nguyen Ngoc Hung (N 10.38607; E 104.99169; 388 meters in elevation) .

Diagnosis. Adult males reaching 85.5 mm SVL, adult females reaching 90.4 mm SVL; 8–10 supralabials, 9– 11 infralabials; 23–30 paravertebral tubercles; 16–20 longitudinal rows of dorsal tubercles; 37–46 rows of ventral scales; six or seven expanded subdigital lamellae proximal to the digital inflection, 11–13 unmodified, distal, subdigital lamellae; 17–20 total subdigital lamellae on fourth toe; enlarged femoral and precloacal scales continuous; 24–33 enlarged femoral scales; proximal femoral scales less than one-half the size of distal proximal scales; 6–8 enlarged precloacal scales with pores on each in males; two or three rows of enlarged post-precloacal scales; two postcloacal tubercles; interdigital pocketing absent; dark pigmented blotches absent on top of head; posterior border of nuchal loop rounded; four dark body bands ( Table 14). These characters are scored across all species of the Cyrtodactylus intermedius complex in Table 7.

Description of holotype. Adult male SVL 80.3 mm; head moderate in length (HL/SVL 0.29) and width (HW/ HL 0.69), somewhat flattened (HD/HL 0.39), distinct from neck, and triangular in dorsal profile; lores concave anteriorly, weakly inflated posteriorly, prefrontal region deeply concave, canthus rostralis rounded; snout elongate (ES/HL 0.39), rounded in dorsal profile; eye large (ED/HL 0.24); ear opening elliptical, obliquely oriented, moderate in size (EL/HL 0.07); eye to ear distance greater than diameter of eye; rostral rectangular, partially divided dorsally by an linear furrow, bordered posteriorly by large left and right supranasals and one large azygous internasal, laterally by first supralabials; external nares bordered anteriorly by rostral, dorsally by large supranasal, posteriorly by three moderately sized postnasals, ventrally by first supralabial; eight right, nine left rectangular supralabials extending to below midpoint of eye, second supralabial slightly larger than first; eight right, nine left 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 sixth 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 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 or seven small, flat scales; similarly sized and spaced tubercles continue onto nape and occiput but diminish in size and distinction on top of head; approximately 19 longitudinal rows of tubercles at midbody between ventrolateral, body folds; 30 paravertebral tubercles; 42 flat, imbricate, ventral scales between ventrolateral body folds much larger than dorsal scales; eight large, pore-bearing, precloacal scales; and no deep precloacal groove or depression.

Forelimbs moderate in stature, relatively short (FL/SVL 0.16); granular scales of forearm larger than those on body, interspersed with large, conical tubercles; palmar scales rounded, slightly raised; interdigital pocketing absent; 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 0.19), 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 13(R) 14(L) enlarged femoral scales in contact with enlarged precloacal scales, terminating just proximal to the inflection of the knee; femoral pores absent; proximal femoral scales onefourth the size of the distal scales, forming abrupt union with smaller, rounded, ventral scales of posteroventral margin of thigh; plantar scales round, slightly raised; interdigital pocketing absent; 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; 18 total subdigital lamellae; and claws well-developed, sheathed by a dorsal and ventral scale at base.

Tail original, 114 mm in length, 6.2 mm in width at base, tapering to a point; dorsal scales of tail flat, square, in transverse rows; tail segmented with six or seven transverse scale rows per segment; posterior margin of segments bordered by three or four moderately sized, flat tubercles dorsally extending to anterior one-third of tail; subcaudal region bearing large, transverse scales for first one-half of tail, second half bearing smaller, irregularly shaped scales; base of tail bearing hemipenal swellings; two postcloacal tubercles on either side of base of hemipenal swellings; and postcloacal scales smooth, flat, large, imbricate.

Coloration in alcohol. Dorsal ground color of head, body, limbs, and tail light-brown; brown nuchal loop with rounded posterior border extends from posterior margin of one eye to posterior margin of other eye, edged with thin, light, lines; four similarly colored dorsal body bands with slightly lightened centers occur between limb insertions; first band terminates at shoulders; second and third bands terminate dorsal to ventrolateral fold; fourth band terminates at anterior margin of hind limb insertions; light edging on body bands generally restricted to the tubercles producing a spotted appearance; body band/interspace ratio 1.3; additional dark-brown postsacral band; and 11 dark and 12 light caudal bands ( Fig 20 ).

Variation. The paratypes closely approach the holotype in coloration ( Fig 20 ). In life, the base a tan color. Edging of dark dorsal bands and tubercles white. The interiors of the body bands are nearly as light as base body coloration. The light caudal bands also contain dark centers ( Fig 21 ).

Distribution. Cyrtodactylus septimontium sp. nov. is known from the Bảy Núi Hill range in western An Giang Province, Vietnam. Bảy Núi translates to “Seven Mountains” in Vietnamese in reference to the hills’ seven prominent peaks. Specimens were collected from two of these hills, Nui Cam and Nui Co To, but it is presumed that the species is found throughout the range.

Etymology. The specific epithet, septimontium , is a noun in apposition in reference to a Latinization of the Vietnamese name for the hill range Bảy Núi meaning the “Seven Mountains”.

Natural history. The type locality of the new species, Nui Cam Mountain is part of the Bảy Núi Mountains – a small range of seven larger mountains and several smaller hills of volcanic origin surrounded by the vast agricultural lowlands of the Mekong Delta flood plain. Nui Cam is the highest of these mountains reaching 710 m in elevation. Bảy Núi mountains are covered by old growth secondary semideciduous forest and highly disturbed forest with numerous granitic outcroppings, large rocks with caverns and caves between them.

At the type locality specimens of Cyrtodactylus septimontium sp. nov. were collected at night (from 19:00 h to 24:00 h) mostly on large granite rocks, occasionally specimens were recorded on tree trunks up to 2.5 m above the ground, or on the forest floor hiding in the leaf litter. Most specimens were recorded on vertical surfaces of large granite rocks or in caverns between them. On Nui Cam Mountain Cyrtodactylus septimontium sp. nov. was most abundant at elevations from ca. 300 to 490 m a.s.l. Sympatric species of lizards recorded with the new species include Cnemaspis nuicamensis Grismer & Ngo , Gehyra mutilata (Wiegmann) , Hemiphyllodactylus sp., Calotes versicolor (Daudin) , Lipinia vittigera (Boulenger) and Scincella cf. rufocaudata (Darevsky & Nguyen). On Nui Co To Mountain Cyrtodactylus septimontium sp. nov. was also recorded mostly on large granite rocks at elevations 350 – 450 m a.s.l., where it was found in sympatry with Cyrtodactylus grismeri Ngo and Cnemaspis tucdupensis Grismer & Ngo.

Comparisons. Cyrtodactylus septimontium sp. nov. is a member of the eastern group sister species to C. intermedius complex incertae sedis 2 from Kirirom National Park from which it is separated by 2.9% sequence divergence ( Table 4). The PCA analysis indicates C. septimontium sp. nov. is well-separated from all other species in morphospace except for overlap with C. bokorensis sp. nov. and C. intermedius ( Figs. 6 ). DAPC analysis shows C. septimontium as distinct from C. bokorensis sp. nov., C. laangensis sp. nov., and C. thylacodactylus sp. nov. but having general overlap with the remaining members of the complex. C. septimontium 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, ventral scales, unmodified, expanded, and total number of subdigital lamellae, enlarged femoral scales, pre-cloacal scales, and post-cloacal tubercles ( Table 6). It differs from C. auralensis sp. nov. by lacking dark blotches on the top of the head. It differs from C. bokorensis sp. nov. in having a nuchal loop with a rounded posterior border. It differs from C. laangensis in having contact between femoral and precloacal scales. It differs from C. cardamomensis and C. thylacodactylus sp. nov. in having proximal femoral scales that are less than half the size of the distal scales. It is further differentiated from C. thylacodactylus sp. nov. in lacking interdigital pocketing ( Table 7).

Remarks. Analysis of five specimens from Kirirom National Park, Cambodia, FMNH 263238-42, shows no morphological differences and they may be conspecific with the populations form the Bảy Núi Hills. The two populations have a sequence divergence of 2.9% ( Table 4) despite a physical distance of 130km. However, for the scope of this research the specimens from Kirirom will not be placed within septimontium sp. nov. due to the great distance and lack of known intermediate populations where gene flow may exist.

Figures

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

FIGURE 20. Type series of Cyrtodactylus septimontium sp. nov. from left to right: Top: holotype LSUHC 12484, paratypes LSUHC 8243-44, 12485-86, 12488, 12487. Middle: NAP 05276-77, 05275, 05274, 05273, 05272. Bottom: paratypes NAP 05321, 05320, 05322, 05324, 05323, 05323.

FIGURE 21. Cyrtodactylus septimontium sp. nov. Top: adult male (Holotype LSUHC 12484) from Nui Cam Mountain, An Giang province, Vietnam (photo by Ngo Van Tri). Middle: adult female from Nui Cam Mountain, An Giang Province, Vietnam (photo by Nikolay A. Poyarkov). Bottom: Granite boulder forest microhabitat from the slopes of Nui Cam Mountain (photo by L. Grismer).