Ptychozoon tokehos

Description of holotype. Adult female SVL 97.5 mm; head moderate (HL / SVL 0.25), wide (HW / HL 0.79), depressed (HD / HL 0.44), distinct from neck; snout rounded at tip in dorsal profile; prefrontal region weakly concave; lores rounded; rostral scale large, rectangular, in contact posteriorly with two supranasals and one postnasal, dorsolaterally with nostrils, and laterally with first supralabials; supralabials (10 R, 9 L) to mid-orbital position; infralabials (12 R, 11 L); nostrils elliptical with long axes oriented obliquely, occupying anterior portion of nasal scale, bordered anteriorly by rostral, dorsally by supranasal, posteriorly by four postnasals of varying sizes (upper largest), and ventrally by first supralabial; scales on rostrum granular larger than granular scales on top of head and occiput; eyes large (ED / HL 0.23), less than snout length; pupil vertically elliptical, crenelated; supraciliaries elongate, posteriormost pointed; auricular opening rounded, bearing a weak supra-auricular ridge; tympanum deeply sunk; infra-auricular flap broad, rounded, extending from below corner of mouth to lateral margin of neck midway between posterior margin of ear opening and forelimb insertion, measuring 5.0 mm at its widest point; dorsal scales of infra-auricular flap large, subimbricate proximally, small juxtaposed distally, ventral scales of flap minute and granular; mental triangular, as wide as deep, bordered laterally by first infralabials and posteriorly by paired, rectangular postmentals, posterior section of left postmental divided into three smaller scales; one row of enlarged sublabials bordering infralabials, anteriormost largest; gular scales granular, grading into larger imbricating throat and subimbricate pectoral and ventral scales. Body dorsoventrally depressed, relatively stout (AXG / SVL 0.53); patagia 8.9 mm at midpoint of body bearing enlarged, subimbricate, rectangular scales dorsally, minute, juxtaposed, subrectangular scales ventrally, ventral surface bearing raised scaly ridges extending from body to edge of flap; 88 minute, flat, round, juxtaposed midbody dorsal scales, largest mid-dorsally; no large, flat, dorsal scales immediately anterior to the hind limb insertions; 36 transverse rows of large, smooth, flat, subimbricate ventral scales much larger than dorsal scales, decreasing in size laterally into granular scales at the base of the flap; 21 enlarged, precloacal scales; five rows of enlarged, post-precloacal scales; and scales immediately anterior to vent granular. Limbs short, robust (FL / SVL 0.10; TBL / SVL 0.17); dorsal scales of forelimbs, flat, juxtaposed, larger than dorsal body scales; ventral forelimb scales small, subimbricate; anterior and posterior margins of forelimbs, and posterior margins of hind limbs bearing wide, cutaneous flaps; that of anterior margin of forearm (i. e. pre-antebrachial flap) emarginated distally and terminates low on the base of digit I, that of the foreleg does not reach the base of digit I; scales of forelimb flaps large, elongate, subimbricate; those of hind limb flaps smaller, more rounded, subimbricate; palmar scales smooth, rounded; digits fully webbed, relatively short, dorsoventrally compressed; undivided transverse subdigital lamellae number 11 (I), 13 (II), 12 (III), 13 (IV), 12 (V), distalmost lamellae V-shaped; claws arise from within the dorsal surface of digital pads; claw of digit I replaced by an enlarged, flat scale; dorsal scales of hind limbs, flat, juxtaposed, same size as dorsal body scales; ventral scales of hind limbs flat, subimbricate, smaller than ventral scales of belly; scales of anterior margin of thigh large, subimbricate; plantar scales smooth, subimbricate; digits fully webbed; transverse subdigital lamellae number 11 (I), 12 (II), 14 (III), 15 (IV), 13 (V), distalmost lamellae V-shaped; claws arise from within the dorsal surface of digital pads, and claw of digit I replaced by an enlarged, flat scale. Tail original, flattened, shorter than SVL (TL / SVL 0.88); two median rows of transversely widened, smooth subcaudals anteriorly becoming less regular and broken up posteriorly; postcloacal scales large, flat, imbricate; dorsal caudals flat, juxtaposed, larger than dorsal body scales, bearing whorls of larger scales; tail width and caudal lobes decrease posteriorly; 22 caudal lobes on each side slightly angled posteriorly; and tail terminates in a short, narrow flap (10.0 mm) bearing smooth edges. Dark phase coloration in life (Fig. 12). Dorsal ground color of head, body, and tail brown; top of head darkly speckled; darker, inverted Y-shaped marking overlying nape and occiput; labial scales lighter than body, delimited by thin, dark lines at their junctures; infra-auricular flap same color as labials; irregularly shaped, white, vertebral markings between and just posterior to the forelimb insertions and in the sacral region; four faint, thin, deeply sinuous dorsal bands between limb insertion transitioning into approximately five wide, faint, caudal bands; terminal caudal band on caudal flap dull-white; subcaudal region mottled, weakly banded; iris bronze; gular region, throat, ventral surfaces of limbs, pectoral region, and belly dull-white with stippled scales. In preservation, the coloration is uniformly dull-grey on all dorsal surfaces with only faint patterning visible. Variation (Fig. 12). Variation in coloration and pattern is highly variable due to this species’ having dark and light color phases and its ability to substrate match. Color pattern variation in the paratypes described here is based on preserved and living material. The paratypes closely approximate the holotype in all aspects coloration and pattern. Caudal banding is present in all specimens in varying degrees of distinctness. FMNH 261852 – 53 have a series of large, irregularly shaped, white, vertebral markings extending from the nape to the postsacral region whereas no other specimens (N = 17) have these markings. FMNH 261852 and 261854 have partially regenerated tails bearing a single flap with no lobes. FMNH 177359, 181844, and 261851 are males bearing 23, 22, and 21 pore-bearing precloacal scales. Variation in meristic characters is presented in Table 8. Comparisons (Tables 4, 5; Figs. 3, 5, 6). Differences between Ptychozoon tokehos sp. nov., P. kabkaebin sp. nov., and P. cicakterbang sp. nov. are listed above in the comparisons sections of those species. Ptychozoon tokehos sp. nov. differs from P. intermedium, P. kuhli, and P. trinotaterra in lacking, as opposed to having, caudal tubercles. From P. intermedium, P. nicobarense, P. rhacophorus, P. trinotaterra, and P. kaengkrachanense it differs in having four body bands as opposed to 0 – 3. Ptychozoon tokehos sp. nov. differs from P. bannaense, P. horsfieldii, P. intermedium, P. kuhli, P. nicobarense, P. rhacophorus, P. trinotaterra, and P. kaengkrachanense in having an emargination between the pre-antebrachial flap and digit I as opposed to no emargination. From P. popaense it differs by having a maximum SVL of 97.5 mm versus 86.2 mm. Ptychozoon tokehos sp. nov. is well-separated from P. cicakterbang sp. nov. and P. lionotum in the PCA and from all species in the DAPC where their 95 % confidence ellipses do not overlap. Ptychozoon tokehos sp. nov. occupies a significantly different position along PC 1 from that of P. cicakterbang sp. nov. and along PC 2, it occupies a significantly different positon from those of P. kabkaebin sp. nov. and P. lionotum. From all other species of the P. lionotum group it is further separated by an uncorrected pairwise sequence divergence of 4.1 – 15.5 %. Combinations of other characters differentiating P. kabkaebin sp. nov. from other more distantly related species are presented in Table 5.

Fig. 12

Diagnosis. Ptychozoon tokehos sp. nov. differs from all other species of Ptychozoon by having the following unique combination of characters: a maximum SVL of 97.5 mm; supranasals not in contact; 8 – 11 supralabials; 10 – 12 infralabials; infra-auricular cutaneous flap; weak supra-auricular ridge present; no dorsal or caudal tubercles; imbricate parachute support scales on dorsal surface of patagia; prominently raised ridges on ventral surface of patagia; 80 – 95 midbody dorsal scales; 30 – 37 ventral scales; an emargination between the pre-antebrachial flap and digit I; no enlarged femoral scales; 20 – 24 pore-bearing precloacal scales in males; 18 – 25 enlarged precloacal scales; 4 – 7 rows of enlarged post-precloacal scales; 13 – 18 transverse subdigital lamellae on the fourth toe; approximately 28 – 34 scales across the widest portion of the caudal flap; enlarged dorsal caudal scales forming intermittent whorls; distal lobes fusing to form a short, narrow, caudal flap; edges of caudal flap smooth; caudal lobes angled posteriorly; caudal lobes variably showing posterior reduction in size; postorbital striping variable; four dark body bands between limb insertions; and irregularly shaped, white, vertebral markings usually not present (absent in 14 of 16 specimens; Tables 4, 5).

Distribution (Fig. 1). Ptychozoon tokehos sp. nov. has a circum-Gulf of Thailand distribution extending from Cat Tien, Dong Nai Province and Phu Quoc Island, Kien Giang Province in southern Vietnam (Nguyen et al. 2009), across the mountainous Cardamom region of southern Cambodia and eastern Thailand, around the Chao Phraya Basin and southward down the Thai-Malay Peninsula of Thailand and Myanmar to at least Hat Yai, Songkla Province, Thailand. Nguyen et al. (2009) report P. tokehos sp. nov. from Trang Bom, Dong Nai Province, in southern Vietnam based on an illustration in Bourret (2009; Fig. 39.) The specimen illustrated however, has three body bands instead of four indicating it may be P. trinotaterra. We have examined photographs of specimens from southern Thailand near the Thai-Malay border from Hat Yai, Songkla (LUSDPC 10946) and Muang Trat, Trat (LSUDPC 10947) that we consider P. tokehos sp. nov. and not P. cicakterbang sp. nov. as they have a weak supra-auricular ridge as opposed to a prominent supra-auricular lobe. Confirmation awaits the examination of these specimens (Grismer et al. in prep).

Etymology. The specific epithet tokehos is the Khmer (Cambodian) word used for Ptychozoon. Natural history. Ptychozoon tokehos sp. nov. is a forest-dwelling species found in hilly areas from sea level to at least 700 m in elevation. This species does quite well in disturbed forests and is commonly found on man-made structures. The holotype and paratypes from Kirirom National Park (FMNH 261851 – 54) were all found during the day (1400 – 1630 h) on or near the exterior walls of a building on a grassy plateau within open pine forest. FMNH 261851 was found on the branch of a large tree abutting an exterior wall, FMNH 261852 was found beneath a layer of paint peeling off the exterior wall of the building approximately 2.5 m above the ground, and FMNH 261853 – 54 were found on the exterior walls. Pauwells et al. (2000) noted that MNHN 1998.590 and 1999.7661 from Phang- Nga were collected from walls inside a forestry department office building where other juveniles and adults were seen. They also observed other specimens inside houses and on the outside of cages in a zoo. MNHN 1999.7661 was carrying two eggs. Additionally they found a pair of the eggs 1.6 m above the ground glued to a tree in evergreen forest of which one contained a fully formed embryo. These observations indicate that the reproductive season of P. tokehos sp. nov. in southern Thailand occurs during mid-February. All paratypes from Bokor National Park (CBC 03162, NCSM 98986 – 87; Fig. 13) were found at night approximately 1.3 m above the ground on the trunks of trees along a trail in disturbed evergreen forest between 315 m and 328 m in elevation. The paratype FMNH 18144 and additional specimens from Sakaerat (FMNH 181823 – 24, 181828 – 29) were collected from an undisturbed lowland forest at approximately 16 m in elevation. The Tanintharyi specimen (USNM 587523) was collected from the trunk of a tree along a logging road in secondary forest at 58 m in elevation. The paratype and additional specimens (FMNH 177358 – 59, 177550) from Khao Chong, Thailand were all collected from primary forest at approximately 130 m in elevation. A hatchling (FMNH 177360) from Khao Chong was collected during June.

Holotype. FMNH 261853 adult female, collected by Bryan L. Stuart and Dara Anon 5 June 2000 from Kirirom National Park, Phnom Sruoch District, Kampong Speu Province, Cambodia (11.32611 ° N, 104.06556 ° E, 700 m in elevation). Paratypes. FMNH 261851 – 52 bear the same collection data as the holotype except they were collected on 3 June 2000. FMNH 261854 bears the same collection data as the holotype except it was collected on 5 November 2000 by Joe Walston. CBC 03162 adult female collected by Neang Thy on 9 June 2017 from Bokor National Park, Teuk Chou District, Kampot Province, Cambodia (10.60156 ° N, 104.03200 ° E, 325 m in elevation). NCSM 98986 adult female collected by Neang Thy on 10 June 2017 from Bokor National Park, Teuk Chou District, Kampot Province, Cambodia (10.60372 ° N, 104.02944 ° E, 328 m in elevation). NCSM 98987 adult female collected by Neang Thy on 12 June 2017 from Bokor National Park, Teuk Chou District, Kampot Province, Cambodia (10.58753 ° N, 104.03269 ° E, 315 m in elevation). FMNH 177359 adult male collected by Edward H. Taylor on 11 June 1969 from the Khao Chong Reserve, Trang Province, Thailand (7.54350 ° N 99.79800 ° E, 127 m in elevation). FMNH 181844 adult male collected by W. Ronald Heyer on 11 June 1969 from Pak Thong Chai District, Nakhon Ratchasima Province, Sakaerat (Environmental Research Station), Thailand (14.50000 ° N, 100.86670 ° E, 16 m in elevation). Additional specimens examined. FMNH 177358 and 177550 adult females collected by Edward H. Taylor on 11 June 1969 from the Khao Chong Reserve, Trang Province, Thailand (7.54350 ° N 99.79800 ° E, 127 m in elevation). FMNH 181823 – 24, 181828 – 29 adult males collected by W. Ronald Heyer on 11 June 1969 from Pak Thong Chai District, Nakhon Ratchasima Province, Sakaerat (Environmental Research Station), Thailand (14.50000 ° N, 100.86670 ° E, 16 m in elevation). USNM 587523 adult female collected by Daniel Mulcahy on 27 May 2015 from the proposed Lenya National Park, Tanintharyi Region, Myanmar (11.05080 ° N 98.91720 ° E, 58 m in elevation). FMNH 177548 adult male collected by Oliver G. Young in 1961 from Chiang Mai, Chiang Mai District, Chiang Mai Province, Thailand (18.79528 ° N 98.99861 ° E, 314 m in elevation). MNHN 1998.590 and 1999.7661 collected on 16 February 1998 by Olivier S. G. Pauwels from the Phang-Nga Wildlife Breeding Station, Muang District, Phang Nga Province, Thailand (8.45014 ° N, 98.525532 ° E, 154 m in elevation).