Bent-toed Gecko Research Articles

Modeling the Distribution of the Ota’s Bent-toed Gecko (Cyrtodactylus otai)

The Ota’s bent-toed gecko (Cyrtodactylus otai) was discovered in isolated karst outcrops of Hang Kia Commune, Mai Chau District, Hoa Binh Province, in 2015 and in Chieng Yen Commune, Van Ho District, Son La Province in 2017, in northwestern Vietnam. This gecko is both an endemic and endangered species of Vietnam, and its known range to date is restricted to a severely fragmented and small regions. Hence, to identify more populations and to better understand the distribution patterns of this cryptic species, we conducted field surveys in surrounding regions of the type localities from 2020 to 2023. We discovered eight new populations for C. otai, and expanded the known range of the species in Van Ho District (Son La Province) and Mai Chau District (Hoa Binh Province). We used species occurrence data from previous studies and our field surveys to model the gecko’s distribution using MaxEnt. The model results showed that the distribution of C. otai may include other nature reserves in surrounding regions, such as Pu Hu and Pu Luong (Thanh Hoa), and Ngoc Son – Ngo Luong (Hoa Binh). Based on the model results, there is a possibility that the Ota’s bent-toed gecko also occur in nearby Lao regions. Therefore, future research and conservation initiatives may focus their efforts in such areas to look for new populations of the Ota’s bent-toed gecko, as well as to assess the distribution, habitat, and ecological patterns of this poorly known reptile.

A new species of karst-dwelling bent-toed gecko of the Cyrtodactylusintermedius group (Squamata, Gekkonidae) from eastern Thailand and the phylogenetic placement of C.intermedius.

A new karst-dwelling bent-toed gecko of the Cyrtodactylusintermedius group is described from Khlong Hat District, Sa Kaeo Province, eastern Thailand, based on an integrative taxonomic analysis of genetic data and morphological characteristics. Phylogenetic analyses using the mitochondrial NADH dehydrogenase subunit 2 (ND2) gene revealed that topotypes of C.intermedius were sister to a clade containing C.kulenensis from Cambodia, an unnamed lineage from Sakaerat Biosphere Reserve in Nakhon Ratchasima Province, Thailand, and the Khlong Hat lineage described here as Cyrtodactyluskhlonghatensis sp. nov. Multivariate analyses of morphometric and meristic characters showed that C.khlonghatensis sp. nov. is morphologically distinct from all other species in the group by having the combination of SVL 76.5-82.8 mm in adult males and 88.5 mm in an adult female; eight supralabial and nine infralabial scales; 30-32 paravertebral tubercles; 20 or 21 longitudinal rows of dorsal tubercles; 43 or 44 ventral scales; seven or eight expanded subdigital lamellae on the 4th toe; 12 unmodified subdigital lamellae on the 4th toe; 19 or 20 total subdigital lamellae on the 4th toe; 31 or 32 total number of enlarged femoral scales; enlarged femoral and precloacal scales continuous; 6-8 pore-bearing precloacal scales in males; three or four rows of enlarged post-precloacal scales; 1-3 postcloacal tubercles; proximal femoral scales less than one-half the size of distal femoral scales; absence of interdigital pocketing between digits of forefeet and hindfeet; and posterior border of the nuchal loop rounded. Uncorrected pairwise genetic divergences (p-distances) between the new species and other species of the intermedius group ranged from 4.73-22.55%. The discovery of this new species exclusively in isolated karst formations from the Thai-Cambodia border suggests that there may be further undiscovered Cyrtodactylus in unexplored karst landscapes along the border of eastern Thailand and western Cambodia.

Additions to the herpetofauna of Hon Son Island, Rach Gia Bay, Kien Giang Province, southern Vietnam with a discussion of syntopy between the granite cave-adapted Bent-toed Gecko Cyrtodactylus eisenmanae and a new Cyrtodactylus of uncertain taxonomic status.

An updated herpetofaunal checklist of Hon Son Island, Rach Gia Bay, Kien Giang Province, southern Vietnam is presented which reports of new records for Kaloula pulchra, Sylvirana cf. mortenseni, Cyrtodactylus sp., and Gehyra mutilata bringing the island total to 21 species. Cyrtodactylus sp. is an unidentified granite-cave adapted species that occurs in syntopy with the granite-cave adapted C. eisenmanae, bringing the total number of Cyrtodactylus on this tiny island (11.5 km2) to three. The implications of highly specialized syntopic congeneric ecomorphs is discussed.

Diet of Invasive Rough Bent-Toed Geckos, Cyrtopodion scabrum (Heyden, 1827), in Southeastern Algeria.

Rough Bent-Toed Gecko, Cyrtopodion scabrum (Heyden, 1827), is an invasive species in Algeria and northwestern Africa. We provide detailed information on the morphometry and diet of C. scabrum from an urban area in Debila (northeastern Oued Souf), Algeria. We found a significant correlation between morphological characters (body length, snout-vent length, and tail length) in individuals within each sex, but no differences in morphometry between females and males. Analysis of stomach contents of 30 specimens (15 adult males, 15 adult females) resulted in identification of 198 prey items belonging to 2 classes, 8 orders, 20 families, and 29 genera. The diet of C. scabrum was mainly composed of arthropods and was highly diverse (Shannon index = 4.3). Insects were the main food item, accounting for 96.5% of prey consumed, followed by arachnids (3.5%). The most important prey categories were Hymenoptera (40.4%), Diptera (19.7%), Lepidoptera (12.6%), and Coleoptera (12.1%).

Bewildering biogeography: Waves of dispersal and diversification across southern Wallacea by bent-toed geckos (genus: Cyrtodactylus)

Bent-toed Geckos, genus Cyrtodactylus, are one of the most diverse terrestrial vertebrate groups, and their range extends from South Asia into Australo-Papua and adjacent Pacific islands. Given the generally high faunal endemism on Wallacean islands, it is rather paradoxical that the diversity in these geckos appears to be so low (21 species in Wallacea, 15 in the Philippines) compared with continental shelf assemblages (>300 species on Sunda + Sahul Shelves + adjacent islands). To determine whether this shortfall was real or an artifact of historical undersampling, we analyzed mitochondrial DNA sequences of hundreds of southern Wallacean samples (Lesser Sundas + southern Maluku). After screening to guide sample selection for target capture data collection, we obtained a 1150-locus genomic dataset (1,476,505 bp) for 119 samples of southern Wallacean and closely related lineages. The results suggest that species diversity of Cyrtodactylus in southern Wallacea is vastly underestimated, with phylogenomic and clustering analyses suggesting as many as 25 candidate species, in contrast to the 8 currently described. Gene exchange between adjacent candidate species is absent or minimal across the archipelago with only one case of > 0.5 migrants per generation. Biogeographical analysis suggests that the hitherto unrecognized diversity is the result of at least three independent dispersals from Sulawesi or its offshore islands into southern Wallacea between 6 and 14 Ma, with one invasion producing small-bodied geckos and the other two or three producing larger-bodied geckos. The smaller-bodied laevigatus group appears to be able to coexist with members of either larger-bodied clade, but we have yet to find members of the two larger-bodied clades occurring in sympatry, suggesting that ecological partitioning or competitive exclusion may be shaping individual island assemblages.

Scratching the surface: a new species of Bent-toed gecko (Squamata, Gekkonidae, Cyrtodactylus) from Timor-Leste of the darmandvillei group marks the potential for future discoveries.

A new species of limestone-dwelling Bent-toed gecko (genus Cyrtodactylus) is described from Nino Konis Santana National Park in the far-east region of Timor-Leste. Both genetic and morphological data strongly support the evolutionary distinctness of the new species, which we describe herein as Cyrtodactylussantana sp. nov. Phylogenetic analysis based on the ND2 mitochondrial gene inferred the new species as part of the C.darmandvillei group with close genetic affinities to C.batucolus, C.seribuatensis, C.petani, C.sadleiri, and two undescribed lineages from the Moluccas in Indonesia. The new species represents the first species of Cyrtodactylus identified at the species level from Timor-Leste and fills an important gap in our understanding of the biogeography and evolutionary history of Cyrtodactylus especially in the Wallacean region. Our results strongly suggest that the diversity of Cyrtodactylus in Wallacea is still underestimated and many more unnamed species remain to be described.

A fortuitous encounter with the invasive gecko, Cyrtopodion scabrum (Heyden,1827) (squamata: Gekkonidae): A new locality of an in the province wilaya of Ouargla, south-east Algeria

The Rough Bent-toed Gecko Cyrtopodion scabrum (Heyden,1827) is one of the invasive species in Algeria and Northwestern Africa. where was it recorded in Algeria, from the east (Souf) and west (Ghardaïa) of north Sahara. In this note, another new locality of this species in the province wilaya of Ouargla, south-east Algeria. C. scabrum is medium-size adult may reach 4.5±0.8Cm of snout vent length and up to 9.5 ±2Cm total length.

How many more species are out there? Current taxonomy substantially underestimates the diversity of bent-toed geckos (Gekkonidae, Cyrtodactylus) in Laos and Vietnam.

Cyrtodactylus is the most diverse genus of the family Gekkonidae and the world's third largest vertebrate genus. The number of species has increased more than fourfold over the last two decades. Indochina, especially Vietnam and Laos, has witnessed a surge in new species discoveries over the last three decades. The species number reported from Laos and Vietnam has remarkably increased from five in 1997 to 71 species in 2021. However, within the genus, several taxonomic issues have not yet been fully resolved. Based on recently collected samples from Laos and Vietnam, we conducted a comprehensive molecular review of Cyrtodactylus occurring in Laos and Vietnam. Our molecular analysis with support from morphological comparisons showed that C.thuongae is a junior synonym of C.dati and C.rufford is a junior synonym of C.lomyenensis. In total, 68 described species distributed in Laos and Vietnam are undisputed with strong support from both molecular and morphological evidence. On the other hand, the molecular analyses revealed that there are at least seven undescribed species in Vietnam and Laos, one in the C.angularis group, one in the C.chauquangensis, and five in the C.irregularis group. This number will likely increase significantly, as previous work suggested that the C.angularis and C.irregularis groups harbor three and six unnamed lineages, respectively. Based on survey gaps identified in our study, it is clear that additional new species will be discovered in poorly studied regions of central Vietnam and northern and southern Laos. As many species in the genus are facing high extinction risks, several undescribed populations might already be severely threatened by human activities in both countries. Therefore, urgent taxonomic research is needed before conservation assessments of newly discovered taxa can be undertaken to protect them from anthropogenic threats.

A new species of bent-toed geckos of the genus Cyrtodactylus Gray, 1827 from western Arunachal Pradesh, India

A new species of bent-toed geckos of the genus Cyrtodactylus is described from western Arunachal Pradesh. The new species is a member of the Indo-Burma clade and is embedded within the “peguensis” group, a relationship deduced contingent on a partial fragment of mitochondrial NADH subunit 2 gene. Cyrtodactylus kamengensissp. nov. is morphologically similar to C. himalayicus from which it differs in bearing a distinct ventrolateral fold and 6–8 basal lamellae on digit IV of pes. Genetically, the new species is sister to the Indian lineage of the “peguensis” group containing C. bhupathyi and C. gubernatoris. The Indian lineage of the “peguensis” group diverged from its Burmese relatives during the mid-Oligocene likely followed by the beginning of the Himalayan uplift, highlighting the role of the Himalayas in the diversification of biota.

A new species of Cyrtodactylus Gray (Squamata: Gekkonidae) from Manipur State, northeast India, with a critical review highlighting extensive errors in literature covering bent-toed geckos of the Indo-Burma region

ABSTRACT A new species of Cyrtodactylus is described from Tamenglong District in northwestern Manipur State, northeast India. The new species is diagnosed from other congeners based on a combination of morphological characters and molecular data (NADH dehydrogenase subunit 2 gene, ND2). Molecular analyses placed the new species as the sister taxon to C. montanus. Due to inconsistencies in the hierarchical clade terminology for Cyrtodactylus species in the Indo-Burma region, recommendations are made for stabilising the terminology and the names for various levels of clades. Based on this revised terminology, the new species was found to be nested within the gansi group of the khasiensis clade, within the Indo-Burma radiation of Cyrtodactylus. A large number of errors and inconsistencies in literature covering species of the Indo-Burma radiation were discovered, particularly in summary tables of measurements and meristic data. Other notable errors found included incorrect identifications of type specimens in figure captions, errors in museum catalogue numbers of type series, incorrect GPS coordinates for type localities, a variety of issues involving GenBank accession numbers and associated data, and many others. We highlight these specific errors and inconsistencies and attempt to clarify or correct them where possible. Suggestions and recommendations are given for authors, journal editors and reviewers on how to improve the accuracy and consistency of morphological and molecular data provided in taxonomic and molecular phylogenetic papers. We also encourage authors and scientific journals to follow or enforce the basic citation guidelines set by NCBI when using sequences downloaded from GenBank, which have been largely overlooked, or ignored. It is hoped that the issues discussed here will be taken as a reminder that errors in peer reviewed papers are an inevitability, and that users of this literature must always carefully assess the accuracy of others’ data when it is important for the interpretation of their results to reduce the propagation of errors in the literature. http://www.zoobank.org/urn:lsid:zoobank.org:pub:9E00496B-C8D0-4391-B1E5-18522B221FBD

A new insular species of the Cyrtodactylus pulchellus group (Reptilia, Gekkonidae) from Tarutao Island, southern Thailand revealed by morphological and genetic evidence

The bent-toed geckos of the Cyrtodactyluspulchellus group are widely distributed along the Thai-Malay Peninsula. Although taxonomic and phylogenetic studies of this species group have been continuously conducted, only some populations from Thailand have been included, resulting in hidden diversity within this group. In this study, we used morphological and molecular data to clarify the taxonomic status and describe a new population from Tarutao Island, Satun Province, southern Thailand. Cyrtodactylusstellatussp. nov. can be distinguished from its congeners by the combination of the following morphological characters: body size; tuberculation; number of dark body bands, ventral scales, and femoroprecloacal pores in males; presence of precloacal pores in females; and scattered pattern on dorsum. Phylogenetic analyses of the mitochondrial ND2 gene recovered the new species as the sister species to C.astrum, with an uncorrected pairwise divergence of 9.78–12.37%. Cyrtodactylusstellatussp. nov. is currently only known from Tarutao Island, Thailand. The discovery of this species suggests that the diversity within the C.pulchellus group remains underestimated and future exploration of unsurveyed areas are needed to further the understanding of this group and its geographic range.

Another New Bent-toed Gecko, genus Cyrtodactylus Gray 1837 (Squamata: Gekkonidae), from Borneo.

To reveal the diversity of Indonesian bent-toed geckos, we pay attention to Kalimantan (Borneo)an island which has received less attention than other Indonesian islands such as Sumatra, Java, Sulawesi, the Moluccas, and the Lesser Sunda archipelagos. About 30 years after Hikida (1990) described three new Cyrtodactylus from Borneo, four more species were described, namely C. limajalur and C. muluensis in 2019, and C. hantu and C. miriensis in 2021, all by Davis et al. Through examination of the collection at MZB and three addition specimens collected from Tawau, we found several undescribed species, one of which we describe here. This new species is easily differentiated from all other congeners by the combination of the following characters: maximum SVL of at least 65.8 mm; no tubercles on dorsal surface of upper arm; tubercles present in the ventrolateral body folds; 2830 paravertebral tubercles; 1720 longitudinal dorsal tubercle rows; 3946 ventral scale rows at midbody; 1719 subdigital lamellae on fourth toe; precloacal pit with 57 pores in males arranged in a wide -shape but absent in females; no enlarged transverse median subcaudals; paired dark brown semilunar-shaped markings on the upper nape. Further study is needed to reveal its molecular phylogenetic position and biogeographical history.

A new species of Cyrtodactylus (Squamata: Gekkonidae) from Ninh Thuan Province, southern Vietnam.

A new species of the Cyrtodactylus irregularis group is described from Ninh Thuan Province, southern Vietnam based on molecular divergence and morphological differences. Cyrtodactylus orlovi sp. nov. is distinguished from the remaining Indochinese bent-toed geckos by having the unique combination of the following characters: size medium (SVL 61.077.7 mm); dorsal tubercles in 1620 irregular rows; 3639 ventral scale rows; precloacal pores absent in females, 5 or 6 in males, in a continuous row; femoral pores absent; 38 enlarged femoral scales; postcloacal spurs 1 or 2; lamellae under toe IV 1619; a continuous neckband; a highly irregular transverse banded dorsal pattern; the absence of transversely enlarged median subcaudal scales. In phylogenetic analyses, the new species was revealed to be the sister taxon to a clade consisting of Cyrtodactylus cattienensis and the most recently described species from Vietnam, C. chungi, with 12.112.4% and 11.7 % pairwise genetic divergence from the two species, respectively, based on a fragment of the mitochondrial COI gene.

A new species of Bent-toed gecko (Squamata: Gekkonidae: Cyrtodactylus Gray, 1827) from the Garo Hills, Meghalaya State, north-east India, and discussion of morphological variation for C. urbanus

Recent taxonomic and systematic research on Cyrtodactylus khasiensis has found that this nomen comprises a large number of superficially similar but deeply divergent species-level taxa from throughout north-east India and surrounding countries. In this study we focus on the taxonomic status of recently surveyed populations from the East Garo Hills and West Garo Hills districts and a single specimen collected from Ri Bhoi District in Meghalaya State, north-east India. Based on a combination of morphological and molecular data we found that the Ri Bhoi specimen is conspecific with the recently described C. urbanus, and that the Garo Hills populations represent a new species of Cyrtodactylus described herein. Molecular analyses (using the NADH dehydrogenase 2, nd2 and adjoining tRNA genes) demonstrate that the new species is nested within the khasiensis group of the Indo-Burma radiation of Cyrtodactylus, and is well-supported as sister to a clade that comprises C. septentrionalis and C. guwahatiensis. We morphologically compare the new C. urbanus specimen with the original description of the species, identify a number of errors and ambiguities in the original description, and notably expand the known morphological variation for the species based on 23 characters. The discovery of an endemic new species of lizards from the Garo Hills further highlights the region as an overlooked centre of biodiversity importance. We discuss several misidentifications in the literature of other reptile species from the region emphasising the need for further attention by taxonomists to review the herpetofauna of the Garo Hills.

A new locality of an invasive Gecko, Cyrtopodion scabrum (Heyden,1827) in Algeria (Squamata: Gekkonidae)

The Rough Bent-toed Gecko Cyrtopodion scabrum (Heyden,1827) was recently recorded in Algeria, from the east part of countries. In this note, another new locality of this species in the central Algeria (Ghardaïa region), situated at 450 km west form the last locality, based on one specimen fond in Bord of Sebkhet. C. scabrum is listed as an invasive species and it was reported as a desert species, in our finding it was recorded in an important wetland (Sebkhet El Melah) which is classified in the Ramsar list in 2004, this statement proves once again the ecological plasticity of this species.

Convergent evolution of karst habitat preference and its ecomorphological correlation in three species of Bent-toed Geckos (Cyrtodactylus) from Peninsular Malaysia

Abstract By studying ecomorophology in the context of phylogeny, researchers can parse out similarity due to common ancestry versus that due to convergence. This is especially true among relatively closely related species where both phylogenetic and environmental constraints may be operating simultaneously. We explored these issues among three karst-associated species from two lineages of Cyrtodactylus—the sworderi group from Peninsular Malaysia and the swamp clade from Peninsular Malaysia and western Indonesia of the agamensis group. A stochastic character mapping analysis using five different habitat preferences corroborated a larger previous analysis in recovering a general habitat preference as an ancestral condition for all habitat preferences and a karst habitat preference in C. guakanthanensis and C. gunungsenyumensis of the sworderi group and C. metropolis of the swamp clade as convergently evolved. Multivariate and univariate analyses of 10 morphometric characters revealed that the ecomorphological similarity between C. guakanthanensis and C. gunungsenyumensis of the sworderi group was also convergent. The ecomorphology of C. metropolis of the swamp clade was intermediate between a karst-adapted ecomorphology and a swamp-generalists ecomorphology. Of the 10 morphometric characters employed in this analysis, only three—head length, head width, and forelimb width—showed any signs of phylogenetic signal. Cyrtodactylus metropolis is hypothesized to be a recently refuged swamp-dwelling species that frequented the Batu Caves environments prior to urbanization of the surrounding swamp habitat to which it is now confined.

A new granite cave-dwelling Bent-toed Gecko from Vietnam of the Cyrtodactylus irregularis group (Squamata; Gekkonidae) and a discussion on cave ecomorphology

An integrative analysis of genetic, morphological, and ecological data recovered a new granite cave-adapted species, Cyrtodactylus raglaisp. nov., from the Song Giang River Valley, Khanh Hoa Province, Vietnam. Cyrtodactylus raglaisp. nov. is nested within one of two major clades within the irregularis species group where it forms a monophyletic group with C. cryptus and its sister species C. kingsadai. It differs from its sister species by an uncorrected pairwise sequence divergence of 16.5% and 16.8% based on the mitochondrial genes NADH dehydrogenase subunit 2 and its flanking tRNAs and the first subunit of cytochrome oxidase c (CO1), respectively. Cyrtodactylus raglaisp. nov. is a narrow-range endemic restricted to a riparian, granite cave microhabitat and its overall morphology bears that of other granite cave-dwelling ecomorphs in the genus. The Song Giang River Valley and its associated waterways are currently threatened by the construction of a hydropower station which will negatively impact the surrounding ecosystem. Urgent field surveys in this region are necessary in order to obtain critical data on its biodiversity and importance to conservation efforts in southern Vietnam.

THE ANTHROPOGENIC ADAPTATION INDEX OF REPTILES IN URBANIZED AREAS OF THE ASHBERON PENINSULA

The strong urbanization of Absheron peninsula highlights the urgency of studying the level of adaptation of reptiles that characterize these areas. Therefore, we have aimed to study the degree of anthropogenic adaptation of each reptile species inhabiting the peninsula. The anthropogenic adaptation index of separate reptiles in the Absheron Peninsula is different in terms of reproductive strategy. Thus, relatively high adaptive anthropogenic intensity is observed in the Caspian bent-toed geckoes (24.5) which are habitats of single-storey buildings, moderately adapted water snakes (17.2), and poorly adapted Mediterranean turtles (10.4). In the mixed-storey residential area, the anthropogenic adaptation were 21.4, 12.8 and 3.7 respectively in geckoes, water snakes and turtles. The anthropogenic adaptation was 0 due to the absence of water snakes and Mediterranean turtles in the residential area with multi-storey buildings, but the Caspian bent-toed gecko was rarely found (1,3). In the area of industrial facilities, the Caspian bent-toed gecko predominates over the reptile species studied, but the level of anthropogenic adaptation in woodlands and control area was much lower.

A new species of geckos of the genus Cyrtodactylus Gray, 1827 from Arunachal Pradesh, India

We here describe a new species of bent-toed geckos from the northeastern Indian state of Arunachal Pradesh, which is widespread across the Dafla and Mishmi hills, occurring at elevations ranging from 179 m to 1400 m. The new species is recovered as sister to the Cyrtodactylus khasiensis clade based on a molecular phylogeny inferred from mitochondrial NADH-ubiquinone oxidoreductase, subunit 2 gene. Intraspecific uncorrected pairwise sequence divergence (p-distance) for the new species was found to be between 0 and 5%, whereas the interspecific divergence from the closely-related congeners was between 19 and 30%. The new species can be differentiated from members of the C. khasiensis clade using a suite of morphological characters: moderate body size (SVL 64.9–81.7); 8–11 supralabials; 8–10 infralabials; 24–26 bluntly conical, feebly keeled dorsal tubercles; 50–60 paravertebral tubercles; ~38 ventral scales between ventrolateral folds; no precloacal groves; 6–10 precloacofemoral pores in a continuous series; 10–16 distal subdigital lamellae on IV of pes; subcaudal scalation of original tail without enlarged plates. This is the fourth reptile species described from Arunachal Pradesh from the expedition led by the team, and this further highlights the need for further herpetological investigations into the region.

Phylogenetic analyses of distantly related clades of bent-toed geckos (genus Cyrtodactylus) reveal an unprecedented amount of cryptic diversity in northern and western Thailand

Cyrtodactylus species are the most diverse of the geckos and are widely distributed in Southeast Asia, including Thailand. However, their patterns of distribution, especially in northern and western parts of Thailand, remain unknown because few Cyrtodactylus species in these regions have been described. Thus, a data set of mitochondrial NADH dehydrogenase 2 (ND2) gene and flanking tRNAs from Cyrtodactylus found in northern and western Thailand, including contiguous areas, was assembled to elucidate phylogenetic relationships and identify the distribution patterns of these geckos. The results showed four well-supported clades, a northwestern clade (A), a northern clade (B), a western clade (C), and a special clade characterized by specific morphological features (D). Clades A–C were grouped with strong support by the geography of their localities from northern Thailand (Mae Hong Son and Chiang Mai Provinces) along the Tenasserim mountain ranges to Phang-Nga Province, Thailand. Clade D is a distinct clade of Cyrtodactylus species characterized by a tuberculate and prehensile tail and distributed widely in mainland Southeast Asia. Overall, the results suggest a pattern of geographic separation and distribution of Cyrtodactylus in northern and western Thailand. Additionally, this study provides evidence of a hidden biodiversity of Cyrtodactylus in these regions.