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Sophina is a poorly known and neglected genus due to the inaccessibility of the Salween Basin, Southern Myanmar. Taxonomic status, distribution, and phylogeny are being revised based on an integrative analysis of genitalia, radula, and molecular data. Morphological variation in shells and genitalia, together with a phylogenetic tree from concatenated data of mitochondrial and nuclear genes, revealed the existence of ten species/subspecies. Penial morphology and genetic divergence were generally consistent and useful in delimiting species, while shell characters showed little overall taxonomic utility in some species. Taxonomic placement of the previous subspecies “bensoni” shows clear distinction in both genitalia and molecular evidence, and is currently recognized as a distinct species. The nominal species “S. schistostelis” and “S. calias” possess similar genitalia and shell morphology, and molecular evidence suggested that they are sister taxa representing geographically isolated populations. Four new species are additionally described herein as S. furfuracea n. sp., S. pisinna n. sp., S. salweenica n. sp., and S. tonywhitteni n. sp. based on both morphology and molecular evidence. Phylogenetic analyses supported monophyly of Sophina, and further a split into two principal clades. These two clades showed little difference in genitalia, but more clear differences in the umbilical area and allopatric distribution in upper and lower reaches of the Gyaing River. High genetic divergence was revealed and this coincided with remarkable degree of endemism and localization with a pattern of one outcrop for one lineage. These data highlight the importance of the Salween Basin's karst ecosystems as an evolutionary and endemic biodiversity hotspot, and indicate that a focus on conservation and management in this area is urgently required.

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A phylogenetic taxonomic analysis of a monophyletic subgroup of the salamandrid genus Tylototriton revealed that a newly discovered population from Ngar Su Village, 1 km south of Ywangan, Shan State, Myanmar is a new species and most closely related to T. shanorum from approximately 80 km to the west in the vicinity of Taunggyi, Shan State. Tylototriton ngarsuensis sp. nov. differs from other closely related species of Tylototriton on basis of varying combinations of characteristics associated with it shorter head, larger size, rib nodule morphology, and overall drab, very dark, coloration, along with its genetic differentiation. Tylototriton ngarsuensis sp. nov. also appears to breed later in the year than most other species. Unfortunately, this species like many other Asian newts, is being harvested for the pet and medicinal trade and given its restricted distribution, this could pose a serious threat to its long-term survival.

Lizards and snakes (squamates) are known for their varied sex determining systems, and gecko lizards are especially diverse, having evolved sex chromosomes independently multiple times. While sex chromosomes frequently turnover among gecko genera, intrageneric turnovers are known only from Gekko and Hemidactylus. Here, we used RADseq to identify sex-specific markers in two species of Burmese bent-toed geckos. We uncovered XX/XY sex chromosomes in Cyrtodactylus chaunghanakwaensis and ZZ/ZW sex chromosomes in Cyrtodactylus pharbaungensis. This is the third instance of intrageneric turnover of sex chromosomes in geckos. Additionally, Cyrtodactylus are closely related to another genus with intrageneric turnover, Hemidactylus. Together, these data suggest that sex chromosome turnover may be common in this clade, setting them apart as exceptionally diverse in a group already known for diverse sex determination systems.

A phylogenetic taxonomy of species in the Cyrtodactylus peguensis group from the Ayeyarwady Basin of Myanmar is constructed based on color pattern, morphology, and molecular systematic analyses using the mitochondrial gene NADH dehydrogenase subunit 2. Newly collected samples from the type locality of C. peguensis and other localities indicate that this clade is endemic to central Myanmar and contains at least seven species, four of which are undescribed. Three species, including C. peguensis occur in the low hills of the Bago Yoma Range within the central portion of the Ayeyarwady Basin. Two of these, C. myintkyawthurai sp. nov. from the northern and central Bago Yoma and C. meersi sp. nov. which is syntopic with C. peguensis in the southern Bago Yoma are described herein. As more lowland hilly areas bordering, and within the Ayeyarwady Basin are surveyed, more new species of this group are likely to be discovered. These discoveries continue the recent surge of descriptions of new species of Cyrtodactylus that are being discovered in Myanmar.

A phylogenetic taxonomic analysis indicates that a newly discovered population of Cyrtodactylus from the vicinity of Ywangan Town in the Shan Hills, Shan State, Myanmar is a new species (C. ywanganensis sp. nov.) and the earliest diverging member of the linnwayensis group within the previously defined Indochinese clade. The DIVALIKE+J model of a BioGeoBEARS biogeographic analysis indicates that the Indochinese clade evolved in the Shan Hills and Salween Basin of eastern Myanmar and dispersed into Indochina on at least three separate occasions from 18.6–13.4 mya. Once there, uplift of the Tenasserim Mountains and Thai Highlands created the intermedius group, the oldhami group, and C. tigroides of western and southern Thailand which form sister lineages to the linnwayensis group, yathepyanensis group, and the sinyineensis group, respectively, of eastern Myanmar. Diverging lineages within the Indochinese clade highlight the importance of the Thai Highlands and Tenasserim Mountains in that group’s evolution and speciation. The discovery of C. ywanganensis sp. nov. in karstic habitats in the Shan Hills continues to underscore the unrealized karst-associated herpetological diversity of this vast, relatively unexplored, upland region and the need for additional field studies.