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.

A new species of Cyrtodactylus Gray, 1827 (Squamata: Gekkonidae) from the Thai-Malay Peninsula and the independent evolution of cave ecomorphology on opposite sides of the Gulf of Thailand.

An integrative taxonomic analysis recovers a distinctive new species of the gekkonid genus Cyrtodactylus Gray, 1827 from Satun Province in extreme southern Thailand as the sister species to the Cyrtodactylus intermedius group of southern Indochina, approximately 600 km to the northeast across the Gulf of Thailand. Based on 1449 base pairs of the mitochondrial gene NADH dehydrogenase subunit 2 (ND2) and its flanking tRNAs, the new species, C. disjunctus sp. nov., bears a pairwise sequence divergence from the mean divergences of the intermedius group species ranging from 17.923.6%. Three different principal component analyses (PCA) and a multiple factor analysis (MFA) recover C. disjunctus sp. nov. as a highly distinctive karst cave-adapted species based on morphology and color pattern. Its sister species relationship to the intermedius groupto which it is added herefurther underscores a growing body of analyses that have recovered a trans-Gulf of Thailand connection across the submerged Sunda Shelf between the southern Thai-Malay Peninsula and southern Indochina. Fragmented karstic archipelagos stretching across Indochina have served as foci for the independent evolution of nearly 25% of the species of Cyrtodactylus. The description of C. disjunctus sp. nov. continues to highlight the fact that karstic habitats support an ever-increasing number of threatened site-specific endemics that compose much of the reptile diversity of many Asian nations but, as of yet, most of these landscapes have no legal protection.