Hiding on jagged karst pinnacles: A new microendemic genus and species of a limestone-dwelling agamid lizard (Squamata: Agamidae: Draconinae) from Khammouan Province, Laos.

We describe a unique new species and genus of agamid lizard from the karstic massifs of Khammouan Province, central Laos. Laodracon carsticola Gen. et sp. nov. is an elusive medium-sized lizard (maximum snout-vent length 101 mm) specifically adapted to life on limestone rocks and pinnacles. To assess the phylogenetic position of the new genus amongst other agamids, we generated DNA sequences from two mitochondrial gene fragments (16S rRNA and ND2) and three nuclear loci ( BDNF, RAG1 and c-mos), with a final alignment comprising 7 418 base pairs for 64 agamid species. Phylogenetic analyses unambiguously place the new genus in the mainland Asia subfamily Draconinae, where it forms a clade sister to the genus Diploderma from East Asia and the northern part of Southeast Asia. Morphologically, the new genus is distinguished from all other genera in Draconinae by possessing a notably swollen tail base with enlarged scales on its dorsal and ventral surfaces. Our work provides further evidence that limestone regions of Indochina represent unique "arks of biodiversity" and harbor numerous relict lineages. To date, Laodracon carsticola Gen. et sp. nov. is known from only two adult male specimens and its distribution seems to be restricted to a narrow limestone massif on the border of Khammouan and Bolikhamxai provinces of Laos. Additional studies are required to understand its life history, distribution, and conservation status.

Two new species of Dixonius from Vietnam and Laos with a discussion of the taxonomy of Dixonius (Squamata, Gekkonidae).

Integrated analyses using maximum likelihood (ML), Bayesian inference (BI), principal component analysis (PCA), discriminate analysis of principal components (DAPC), multiple factor analysis (MFA), and analysis of variance (ANOVA) recovered two new diagnosable species of gekkonid lizards in the genus Dixonius, one from the Central Highlands, Gia Lai Province, Vietnam and another from the Vientiane Province, Laos. Phylogenetic analyses based on the mitochondrial NADH dehydrogenase subunit 2 gene (ND2) and adjacent tRNAs showed that Dixoniusgialaiensissp. nov. is the sister species of D.minhlei from Dong Nai Province, Vietnam and is nested within a clade that also includes the sister species D.siamensis and D.somchanhae. Dixoniusmuangfuangensissp. nov. is the sister species to D.lao from Khammouane Province, Laos and is embedded in a clade with D.vietnamensis, D.taoi, and undescribed species from Thailand. Multivariate (PCA, DAPC, and MFA) and univariate (ANOVA) analyses using combinations of 15 meristic (scale counts), six morphometric (measurements), and five categorical (color pattern and morphology) characters from 44 specimens encompassing all eight species of Dixonius from Vietnam and Laos clearly illustrate Dixoniusgialaiensissp. nov. and Dixoniusmuangfuangensissp. nov. are statistically different and discretely diagnosable from all closely related species of Dixonius. These integrative analyses also highlight additional taxonomic issues that remain unresolved within Dixonius and the need for additional studies. The discovery of these new species further emphasizes the underappreciated herpetological diversity of the genus Dixonius and illustrates the continued need for field work in these regions.

First record of the Cyrtodactylus brevipalmatus group (Squamata: Gekkonidae) from Vietnam with description of a new species.

A new species of the genus Cyrtodactylus is described from Dien Bien Province, northwestern Vietnam based on morphological and molecular data. Cyrtodactylus ngati sp. nov. can be distinguished from remaining congeners by the following combination of characters: maximum SVL 69.3 mm; dorsal pattern consisting of six dark irregular transverse bands between limb insertions; inter-supranasals one; dorsal tubercles present on occiput, body, hind limbs and on first half of tail; 1722 irregular dorsal tubercle rows at midbody; lateral folds clearly defined, with interspersed tubercles; 3238 ventral scales between ventrolateral folds; 13 precloacal pores separated by a diastema of 5/5 poreless scales from a series of 7/7 femoral pores in enlarged femoral scales; precloacal and femoral pores absent in females; 13 postcloacal tubercles on each side; transversely enlarged median subcaudal scales absent. In the molecular analyses, the new species is shown to be the sister taxon to C. interdigitalis from Thailand. This is the 47th species of the genus Cyrtodactylus and the first member of the C. brevipalmatus species group recorded from Vietnam.

A new species of Dixonius (Squamata: Gekkonidae) from Vientiane Capital, Laos.

A new species of the gekkonid genus Dixonius is described from Huaysorn-Huaysua village, Nasaithong District, Vientiane Capital, Laos. The new species can be distinguished from all other species by a combination of the following characters: maximum SVL 47.1 mm; 1921 longitudinal rows of dorsal tubercles at midbody; 2326 longitudinal rows of ventrals across the abdomen; 7 or 8 supralabials, 6 in mid-orbital position; 5 or 6 infralabials; 5 or 6 precloacal pores in males, femoral pores lacking; precloacal and femoral pores absent in females; a canthal stripe running from rostrum through the eye and terminating at back of head; dorsum brown with irregular dark marks. In phylogenetic analyses, the species is recovered as the sister taxon to D. siamensis, which occurs in Laos, Thailand, and Vietnam. Genetically, the two species are approximately 9.4% divergent from each other based on the complete mitochondrial ND2 gene with six partial or complete adjacent tRNAs. It is the 12th species known in the genus Dixonius and the second Dixonius species described from Laos.

A new species of the Gekko japonicus group (Squamata: Gekkonidae) from Khammouane Province, central Laos.

A new species of the Gekko (Japonigekko) japonicus group from Khammouane Province, central Laos is described based on morphological characters and molecular evidence. Morphologically, Gekko khunkhamensis sp. nov. can be distinguished from the remaining congeners by a combination of the following characters: size moderate (SVL 69.775.2 mm); nares in contact with rostral; internasals absent; postmentals enlarged; interorbital scales between anterior corners of the eyes 31 or 32; dorsal tubercles absent; ventrals between mental and cloacal slit 181185; midbody scales 127138; ventral scales 4245; subdigital lamellae on first toe 13 or 14, on fourth toe 14 or 15; tubercles on upper surface of fore and hind limbs absent; precloacal pores absent in the male and females; postcloacal tubercles 2; tubercles absent on dorsal surface of tail base; subcaudals distinctly enlarged; dorsal surface of body with five dark grey bands, which become irregular posteriorly. Genetically, the new species is placed in a clade, consisting of G. bonkowskii, G. nadenensis, G. scientiadventura, G. sengchanthavongi, and G. thakhekensis and differs from other congeners by at least 13% in terms of pairwise distance based on a fragment of the mitochondrial ND2 gene.

Two new species of Cyrtodactylus (Squamata: Gekkonidae) from northern Laos, including new finding and expanded diagnosis of C. bansocensis.

Two new Cyrtodactylus species are described from Houaphan and Luang Prabang provinces in Laos based on morphological and molecular data. Cyrtodactylus houaphanensis sp. nov. differs from all other Cyrtodactylus in the C. wayakonei species group by at least 3.3 % genetic divergence in the COI gene and can be diagnosed in morphology as follows: SVL 75.8 mm; supralabials 9 or 10; infralabials 8 or 9; ventral scales 35; dorsal tubercles in 20 rows at midbody; precloacal pores 6 in the male; femoral pores absent; subcaudals enlarged; five irregular, brown bands between limb insertions. The new species morphologically resembles C. chauquangensis and revealed to be a sister taxon to C. puhuensis according to our genetic analyses, from which it mainly differs in the absence of enlarged femoral scales. Cyrtodactylus ngoiensis sp. nov. differs from other closely related congeners by at least 11.6 % genetic divergence in the COI gene and can be diagnosed in morphology as follows: maximum SVL 95.3 mm; supralabials 6-9; infralabials 8-11; ventral scales 38-43; dorsal tubercles in 15-21 rows at midbody; enlarged femoral scales present; precloacal pores 7 in the male, 7 pitted scales in females; femoral pores 14 in the male, absent in females; five bright yellowish transverse dorsal bands; subcaudals enlarged. The new species is shown to be a member of the C. wayakonei species group, but morphologically resembles C. dumnuii from Thailand. According to our phylogenetic analyses, it is a basal taxon to a clade comprising C. spelaeus, C. chauquangensis, C. vilaphongi, C. cucphuongensis, C. puhuensis, C. houaphanensis, C. otai and C. bobrovi. Based on a new record of C. bansocensis from central Laos, which represents the first recorded female we provide a redescription of C. bansocensis including expanded diagnosis. In addition, an updated identification key for the Cyrtodactylus known from Laos is provided.

A new species of Dixonius (Squamata: Gekkonidae) from the karst forest of Khammouane Province, central Laos.

A new species of Dixonius is described on the basis of three specimens from the karst forests around Thakhek town, Khammouane Province, Laos. The new species from Laos can be distinguished from other species of Dixonius based on molecular and morphological divergences. It is characterized by a maximum SVL of 55.4 mm; 20-23 longitudinal rows of dorsal tubercles at mid-body; 23-24 longitudinal rows of ventrals across the abdomen; 8-10 supralabials, 7 or 8 in mid-orbital position; 7 or 8 infralabials; 8 precloacal pores in male; the male without femoral pores; precloacal and femoral pores absent in females; uniformly pebble brown dorsum. In phylogenetic analyses, the new species is shown to be the sister taxon to two undescribed taxa from Thailand but differs by at least 8.6% in genetic pairwise distance from the latter based on the complete sequences of the mitochondrial ND2 gene with partial or complete sequences of six adjacent tRNAs. This is the ninth known species of Dixonius, and the second recorded species from Laos.

A new species of Cyrtodactylus (Squamata: Gekkonidae) from Vientiane Province, northern Laos.

A new species of the genus Cyrtodactylus from Vientiane Province, northern Laos is described based on morphological and molecular data. Cyrtodactylus muangfuangensis sp. nov. can be distinguished from remaining congeners by the following combination of characters: maximum SVL 83.9 mm; dorsal pattern consisting of dark nuchal loop, nape band and five dark transversal bands between limb insertions; intersupranasals two; dorsal tubercles present on occiput, body, hind limbs and tail base; 15 or 16 irregular dorsal tubercle rows at midbody; lateral folds clearly defined, without interspersed tubercles; 31-37 ventral scales between ventrolateral folds; six precloacal pores and 15 femoral pores in males, which are interrupted by six to eight poreless scales; six precloacal pitted scales plus in total 10-15 pitted femoral scales in females, which are separated by six to eight poreless scales; enlarged precloacal and femoral scales present; two or three postcloacal tubercles; median subcaudal scales transversely enlarged. In molecular analyses, the new species is strongly supported as a member of the Cyrtodactylus phongnhakebangensis species group, and weakly corroborated as a sister taxon to C. pageli. Pairwise genetic comparison shows that it is at least 18% divergent from other congeners in the species group based on a fragment of the mitochondrial cytochrome C oxidase subunit I gene.