A new potentially endangered limestone-associated Bent-toed Gecko of the Cyrtodactylus pulchellus (Squamata: Gekkonidae) complex from northern Peninsular Malaysia.

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A survey of a limestone forest at Gunung Baling, Kedah, West Malaysia lead to the discovery of an undescribed species of Bent-toed Gecko from the Cyrtodactylus pulchellus complex. Cyrtodactylus evanquahi sp. nov. can be distinguished from all other species in the C. pulchellus complex by a suite of morphological and color pattern characteristics: prominent tuberculation, higher number of dark body bands, and a smaller maximum SVL. It is further differentiated from all other species as follows; no tubercles on the ventral surface of the forelimbs, gular region, or in the ventrolateral folds; 31-34 paravetebral dorsal tubercles; 18-23 longitudinal rows of tubercles; 29-33 ventral scales; 22-23 subdigital lamellae on the fourth toe; 32-36 femoroprecloacal pores; a shallow precloacal groove in males; body bands and nuchal loop edged with a thin white line bearing tubercles; no scattered white spots on the dorsum; six or seven dark body bands much thinner than interspaces; 9-11 dark caudal bands on original tail; bands on the original tail separated by immaculate white caudal bands. It is further differentiated by an uncorrected pairwise genetic divergence of 6.50-15.67% from all other congeners in the C. pulchellus complex. It is most closely related to C. pulchellus from Penang Island ∼76 km to the southwest. In addition to the new samples from Gunung Baling, we added four samples of C. bintangrendah from the new locality of Belukar Semang, Perak. The discovery of yet another new species of the C. pulchellus complex from a limestone habitat continues to underscore the high degree of endemism and the importance of these unique habitats for biodiversity, and the continued need for their conservation.

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  • 10.3897/zookeys.858.34297
Morphological and molecular analyses reveal two new insular species of Cnemaspis Strauch, 1887 (Squamata, Gekkonidae) from Satun Province, southern Thailand.
  • Jul 1, 2019
  • ZooKeys
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We describe two new insular gecko species of the genus Cnemaspis from Tarutao, Adang, and Rawi islands in Satun Province, southern Thailand. The new species are distinguished from their congeners in having a unique combination of morphological, scalation, and color pattern characters, and by genetic divergence in the mitochondrial NADH dehydrogenase subunit 2 (ND2) gene. Cnemaspistarutaoensissp. nov. was found to be a member of the C.kumpoli group, but is distinguished from all other species in that group by having 8–9 supralabials and 8 infralabials; 4–5 pore-bearing precloacal scales, pores rounded; 17–19 paravertebral tubercles randomly arranged; 27–29 subdigital lamellae under the fourth toe; subcaudal region yellowish, with smooth scales and a single enlarged median row; black gular markings in males and females; and 17.24–22.36% uncorrected pairwise sequence divergences. Cnemaspisadangrawisp. nov. was found to be a member of the C.siamensis group, but is distinguished from all other species in that group by having 10 supralabials and 9 infralabials; 6–8 pore-bearing precloacal scales, pores rounded and arranged in a chevron shape; 23–25 randomly arranged, separated paravertebral tubercle rows; 26–28 subdigital lamellae under the fourth toe; subcaudal scales keeled, without enlarged median row; gular region, abdomen, limbs and subcaudal region yellowish in males only; gular marking absent in males and females; and 8.30–26.38 % uncorrected pairwise sequence divergences. Cnemaspistarutaoensissp. nov. occurs in karst formations on Tarutao Island, while Cnemaspisadangrawisp. nov. is found near granitic, rocky streams on Adang and Rawi islands.

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  • 10.3897/zookeys.1125.94060
Hidden diversity of rock geckos within the Cnemaspissiamensis species group (Gekkonidae, Squamata): genetic and morphological data from southern Thailand reveal two new insular species and verify the phylogenetic affinities of C.chanardi and C.kamolnorranathi.
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  • ZooKeys
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Two new insular rock geckos in the genus Cnemaspis are described from Ko Samui in Surat Thani Province and Ko Similan in Phang-nga Province, southern Thailand, based on a combination of morphological and mitochondrial NADH dehydrogenase subunit 2 (ND2) data. Both new species represent divergent lineages within the Cnemaspissiamensis species group. Cnemaspissamui sp. nov. is distinguished from other species in the group by having eight or nine supralabial and infralabial scales; 5-8 pore-bearing precloacal scales in males, pores rounded; 25-27 paravertebral tubercles, arranged randomly; 22-25 subdigital lamellae under 4th toe; enlarged median subcaudal scale row present; gular region, abdomen, limbs and subcaudal region yellowish only in males, and uncorrected pairwise divergences of 8.86-26.83% from all other species in the C.siamensis species group. Cnemaspissimilan sp. nov. is distinguished from other species in the group by having eight or nine supralabial and seven or eight infralabial scales; one pore-bearing precloacal scale in males, pore rounded; 24 or 25 paravertebral tubercles, arranged randomly; 23 or 24 subdigital lamellae under 4th toe; no enlarged median subcaudal scale row; pale yellow reticulum on head, neck, flanks, belly and limbs in male only, and uncorrected pairwise divergences of 9.34-27.11% from all other species in the C.siamensis species group. Cnemaspissamui sp. nov. is found along granitic rocky stream outcrops of Hin Lad Waterfall, Ko Samui, Gulf of Thailand, while Cnemaspissimilan sp. nov. occurs in granitic rocky outcrops near Ao Nguang Chang Bay, Ko Similan, Andaman Sea. The phylogenetic analyses confirmed that C.chanardi and C.kamolnorranathi are also nested within the C.siamensis species group, as previously hypothesized from morphology and color pattern characters.

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  • 10.11646/zootaxa.4175.4.5
Historical considerations and comments on the type series of Cyrtodactylus marmoratus Gray, 1831, with an updated comparative table for the bent-toed geckos of the Sunda Islands and Sulawesi.
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Cyrtodactylus marmoratus Gray, 1831, a species of bent-toed gecko exhibiting a precloacal groove in males, was described on the basis of specimens collected by Heinrich Kuhl and Johan Conrad vanHasselt in Java, Greater Sunda Islands, Indonesia. Kluge (1985) subsequently designated a lectotype for C.marmoratus from a series of these specimens (i.e., syntypes), now housed in the herpetological collection at Naturalis (formerly the Rijksmuseum van Natuurlijke Historie; RMNH), Leiden, the Netherlands. Our work at Naturalis shows that the type series of C.marmoratus at RMNH actually comprises two sets of specimens, and that examination of specimens from one set or the other by different authors, including Kluge (1985), is responsible for some confusion surrounding the type series of this species. As a consequence, we present relevant morphological data for all 14 specimens constituting the type series of C.marmoratus at RMNH for the first time. The type status of two specimens of C.marmoratus in the collection at the Muséum National d'Histoire Naturelle, Paris, France, remains unresolved at present. Owing to the inconsistent naming and application of terms for some key characters (e.g., groove, sulcus, pit, hollow, depression) used in the diagnoses of Cyrtodactylus species, we here propose a set of novel and useful definitions that are supported by photographs. We also illustrate the sexually dimorphic expression of this character in C.marmoratus. Finally, we present a revised comparative table for the bent-toad geckos of the Sunda Islands and Sulawesi.

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A new species of bent-toed gecko, genus Cyrtodactylus Gray, 1827 (Reptilia: Squamata: Gekkonidae), from Jawa Timur Province, Java, Indonesia, with taxonomic remarks on C. fumosus (Müller, 1895).
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  • Zootaxa
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Hiding in plain sight: a new species of bent-toed gecko (Squamata: Gekkonidae: Cyrtodactylus) from West Timor, collected by Malcolm Smith in 1924.
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  • Research Article
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Species of bent-toed gecko (Cyrtodactylus) in Vietnam have been described at a rate of nearly four species per year since 2007 mostly based on morphological data. A tool that guides species delimitation will accelerate the rate of documentation, and at a time when the recognition of species greatly benefits conservation. We use DNA barcoding using COI (550 bp) to re-examine the levels of genetic divergence and taxonomic status of 21 described species of Vietnamese bent-toed geckos. Tree-based analyses resolve all sampled species and identify potential undescribed taxa. Kimura 2-parameter genetic distances between the described species average 21.0±4.2% and range from 4.3% to 28.7%. Further, our analyses discover two potentially new species from Vietnam, two from Laos and one from China. Herein we describe the new species Cyrtodactylus puhuensis sp. nov. from Vietnam on the basis of both genetics and morphology. Genetically, it differs from the remaining species by an average K2P distance of 24.0±1.8%. Morphologically, the new species is diagnosed by its medium-size (snout-vent length 79.24 mm and tail length 82.59 mm, for the single known individual), in having a series of moderately enlarged transverse subcaudals and a series of moderately enlarged femoral scales that extend from precloacal scales, in possessing femoral scales without pores, with males having five precloacal pores, and in exhibiting 8 supralabials, 10 infralabials, 23 narrow subdigital lamellae on its fourth toe, and 36 transverse ventrals.

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  • Cite Count Icon 6
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Two new karst-adapted species in the Cyrtodactyluspulchellus group (Reptilia, Gekkonidae) from southern Thailand.
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  • ZooKeys
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The exploration of unsurveyed areas in southern Thailand discovered two new karst-adapted species, Cyrtodactylussungaiupesp. nov. and Cyrtodactyluswangkhramensissp. nov., from Thung Wa and La-ngu Districts, Satun Province, respectively. These new species are members of the C.pulchellus group that occur along the Thai-Malay Peninsula. The new species can be distinguished from all other congeners by their key morphological characters and genetic divergence. Morphologically, Cyrtodactylussungaiupesp. nov. and Cyrtodactyluswangkhramensissp. nov. can be diagnosed from other members by having a combination of differences in body size; degree of dorsal tuberculation; absence of tubercles on ventral surfaces; number of ventral scales, paravertebral tubercles and femoroprecloacal pores in males only; deep precloacal groove only in males; absence of a scattered pattern of white dorsal tubercles; number of dark body bands; and the extent of caudal tubercles on an original tail. Although the two species are sister taxa and have nearly identical morphologies, they are considered to be different species, based on a relatively high uncorrected pairwise genetic divergence of the mitochondrial ND2 gene (6.59-6.89%), statistically significant univariate and multivariate morphological differences (PERMANOVA and ANOVA) and diagnostic characteristics of caudal tuberculation on the original tail. Moreover, Cyrtodactylussungaiupesp. nov. and Cyrtodactyluswangkhramensissp. nov. are currently restricted to their karstic type localities which may serve as a geographic barrier to dispersal and gene flow.

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An integrative taxonomic analysis based on the mitochondrial gene ND2 and its flanking tRNAs, morphology, and color pattern indicates that a newly discovered gecko described herein as Hemiphyllodactylus cicak sp. nov. from Penang Hill on the Island of Penang, Peninsular Malaysia is a member of the H. harterti group. Hemiphyllodactylus cicak sp. nov. is most closely related to the clade composed of the sister species H. harterti from Bukit Larut, Perak in the Bintang Mountain Range and H. bintik from Gunung Tebu, Terengganu from the Timur Mountain Range. These three allopatric species form a monophyletic group that extends approximately 270 km across three isolated mountain ranges in northern Peninsular Malaysia. The molecular analysis also indicates that H. titiwangsaensis from the Titiwangsa Mountain Range is composed of three genetically distinct allopatric populations. The southern two populations from Fraser's Hill and Genting Highlands, Pahang have an uncorrected pairwise sequence divergence of 3.5% whereas these two populations have 12.4 and 12.8 % sequence divergences, respectively, from the northern population at Cameron Highlands, Pahang. Although the high sequence divergence clearly distinguishes the southern two populations from the former as a different species, all three populations are morphologically indistinguishable, leading to the hypothesis of a true, cryptic speciation event.

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A new species of geckos of the genus Cyrtodactylus Gray, 1827 from Arunachal Pradesh, India
  • Jan 28, 2021
  • Evolutionary Systematics
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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.

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  • 10.11646/zootaxa.2419.1.2
Another new Rock Gecko (genus Cnemaspis Strauch 1887) from Pulau Langkawi, Kedah, Peninsular Malaysia
  • Apr 6, 2010
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A new species of forest dwelling Rock Gecko, Cnemaspis roticanai sp. nov., is described from the upper elevations of Gunung Raya, Pulau Langkawi, Kedah, Peninsular Malaysia. Cnemaspis roticanai is the second species of Cnemaspis described from Pulau Langkawi and is differentiated from all other Southeast Asian Cnemaspis in having a unique combination of color pattern and scale characteristics including keeled subtibials, ventrals, subcaudals, dorsal tubercles, and forearm scales; 25–27 paravertebral tubercles; a median row of enlarged, keeled subcaudals; five or six precloacal, pore-bearing scales in males separated medially by one or two non-pore-bearing scales; 26–29 subdigital lamellae on the fourth toe; no dark, longitudinal gular markings or blotches; no dark shoulder patch enclosing a white to yellow ocellus; and having a yellow to white, prescapular crescent. Cnemaspis roticanai is the latest species in a growing list of new taxa being discovered from the Langkawi Archipelago.

  • Research Article
  • Cite Count Icon 23
  • 10.11646/zootaxa.1875.1.4
A new species of karst dwelling gecko (genus Cnemaspis Strauch 1887) from the border region of Thailand and Peninsular Malaysia
  • Sep 12, 2008
  • Zootaxa
  • L. LEE GRISMER + 3 more

A new species of karst dwelling gecko, Cnemaspis biocellata sp. nov. is described from the border region in the Satun Province of southern Thailand and the state of Perlis in northern Peninsular Malaysia. Cnemaspis biocellata sp. nov. is differentiated from all other species of Southeast Asian Cnemaspis by having a maximum SVL of 40.1 mm; 6–10 supralabials; 5–7 infralabials; weakly keeled scales on anterior portion of forearm; smooth ventral scales; no femoral pores; 8–12 precloacal pores; smooth subcaudals with an enlarged median row; one or two cloacal tubercles; 29–37 subdigital lamellae on fourth toe; no dark bands encircling tail; two distinct, white, well defined, occipital ocelli; a black occipital band bordering a series of closely spaced, large, white to yellow spots which form a nuchal band and a small, black shoulder patch enclosing a single white to yellow ocellus. This species is restricted to the karst formations of the Nakawan Range spanning the Thai-Malaysian border and has been misidentified as C. siamensis by previous authors.

  • Research Article
  • Cite Count Icon 29
  • 10.11646/zootaxa.1931.1.1
The distribution, taxonomy, and redescription of the geckos Cnemaspis affinis (Stoliczka 1887) and C. flavolineata (Nicholls 1949) with descriptions of a new montane species and two new lowland, karst- dwelling species from Peninsular Malaysia
  • Nov 12, 2008
  • Zootaxa
  • L Lee Grismer + 3 more

We provide data supporting the continued recognition of Cnemaspis affinis (Stoliczka) and Cnemaspis flavolineata (Nicholls) as separate species and restrict their distribution to Pulau Pinang, Penang for the former and the Titi Wangsa Range and Gunung Benom, Peninsular Malaysia for the latter. For the montane population of Cnemaspis from Bukit Larut, Perak, which has been referred to as both C. affinis and C. kendallii, we demonstrate that it is discretely diagnosable from all other Southeast Asian Cnemaspis on the basis of size and numerous color pattern and scale characteristics and for it we provide the new name Cnemaspis mcguirei sp. nov. Two new lowland, karst-dwelling species from isolated locations along the foothills of the Titi Wangsa and Timur ranges in northern Peninsular Malaysia are demonstrably differentiable from all other Southeast Asia Cnemaspis on the basis of color pattern and scale morphology and are described herein as Cnemaspis karsticola sp. nov. from Gunung Reng, Kelantan and Cnemaspis bayuensis sp. nov. from Kampung Bayu, Kelantan.

  • Research Article
  • Cite Count Icon 19
  • 10.1093/rpd/ncr230
Measurements of 222Rn activity concentration in domestic water sources in Penang, northern peninsular Malaysia
  • Jun 3, 2011
  • Radiation Protection Dosimetry
  • B G Muhammad + 3 more

Measurements of (222)Rn activity concentration were carried out in 39 samples collected from the domestic and drinking water sources used in the island and mainland of Penang, northern peninsular, Malaysia. The measured activity concentrations ranged from 7.49 to 26.25 Bq l(-1), 0.49 to 9.72 Bq l(-1) and 0.58 to 2.54 Bq l(-1) in the raw, treated and bottled water samples collected, respectively. This indicated relatively high radon concentrations compared with that from other parts of the world, which still falls below the WHO recommended treatment level of 100 Bq l(-1). From this data, the age-dependent associated committed effective doses due to the ingestion of (222)Rn as a consequence of direct consumption of drinking water were calculated. The committed effective doses from (222)Rn resulting from 1 y's consumption of these water were estimated to range from 0.003 to 0.048, 0.001 to 0.018 and 0.002 to 0.023 mSv y(-1), for age groups 0-1, 2-16 and >16 y, respectively.

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