species, display a remarkable diversity of reproductive modes -aquatic breeding, terrestrial gel nesting, terrestrial foam nesting and terrestrial direct development. The evolution of these modes has until now remained poorly studied in the context of recent phylogenies for the clade. Here, we use newly obtained DNA sequences from three nuclear and two mitochondrial gene fragments, together with previously published sequence data, to generate a well-resolved phylogeny from which we determine major patterns of reproductive-mode evolution. We show that basal rhacophorids have fully aquatic eggs and larvae. Bayesian ancestral-state reconstructions suggest that terrestrial gel-encapsulated eggs, with early stages of larval development completed within the egg outside of water, are an intermediate stage in the evolution of terrestrial direct development and foam nesting. The ancestral forms of almost all currently recognized genera (except the fully aquatic basal forms) have a high likelihood of being terrestrial gel nesters. Direct development and foam nesting each appear to have evolved at least twice within Rhacophoridae, suggesting that reproductive modes are labile and may arise multiple times independently. Evolution from a fully aquatic reproductive mode to more terrestrial modes (direct development and foam nesting) occurs through intermediate gel nesting ancestral forms. This suggests that gel nesting is not only a possible transitional state for the evolution of terrestriality, but also that it is a versatile reproductive mode that may give rise to other terrestrial reproductive modes. Evolution of foam nesting may have enabled rhacophorids to lay a larger number of eggs in more open and drier habitats, where protection from desiccation is important. Terrestrial direct development allows frogs to lay eggs independent of bodies of water, in a diversity of humid habitats, and may represent a key innovation that facilitated the evolution of nearly half of all known rhacophorid species.

Anurans in Peninsular India exhibit close biogeographical links with Gondwana as well as Laurasia, often explainable by the geological history of the Indian subcontinent; its breakup from Gondwanan landmasses followed by long isolation that resulted in diversification of endemic lineages, and subsequent land connections with Asia that enabled dispersal of widespread groups. Although widely distributed, the frog subfamily Microhylinae mostly comprises of geographically restricted genera found either in Southeast and East Asia or Peninsular India and Sri Lanka. Here we report a previously unknown microhylid from the Western Ghats in Peninsular India with closest relatives found over 2,000 km away in Southeast Asia. Based on integrated evidence from mitochondrial and nuclear DNA, adult and tadpole morphology, hand musculature, male advertisement call, and geographical distance, we recognize this enigmatic frog as a distinct new species and genus endemic to the Western Ghats. The discovery of Mysticellus franki gen. et sp. nov. and its close evolutionary relationship with the Southeast Asian genus Micryletta also provide insights on the biogeography of Microhylinae. Genus-level divergences within the subfamily suggest multiple Cenozoic biotic exchange events between India and Eurasia, particularly through postulated Eocene land bridges via Southeast Asia prior to accretion of the two landmasses.

A systematic revision of the genus Hylarana in the Western Ghats-Sri Lanka biodiversity hotspot is presented. Species delineation in Hylarana is complicated due to a lack of distinct colour differences or striking morphological characters, leading to potential misidentification. We conducted extensive surveys throughout the Western Ghats-Sri Lanka biodiversity hotspot and performed multiple gene (16S, COI and Cytb) barcoding using 103 samples collected from cultivated land and natural habitats. Genetic distance comparisons and Neighbor Joining trees indicated the presence of at least 14 candidate species in the region, supported by taxa groupings for all three genetic markers. Utilising a combination of molecular and morphological data, we describe seven new species, doubling the number of Hylarana species previously known from this region. We further demonstrate that H. temporalis, which was originally described from Sri Lanka, was misidentified with the Western Ghats endemic species for nearly 100 years. Conversely, H. aurantiaca was originally described from the Western Ghats and misidentified in Sri Lanka. Our study confirms that the distribution of H. temporalis is restricted to Sri Lanka, while H. aurantiaca is endemic to the Western Ghats, and that there are no shared Hylarana species between the two regions. Hylarana flavescens, H. intermedius and H. montanus, previously considered synonyms of H. temporalis are confirmed as valid species. Hylarana bhagmandlensis is removed from the synonymy of H. aurantiaca and placed as a junior subjective synonym of H. montanus. To establish nomenclatural stability, H. flavescens, H. malabarica and H. temporalis are lectotypified and H. intermedius is neotypified. Detailed descriptions, diagnosis, morphological and genetic comparisons, illustrations and data on distribution and natural history are provided for all species. Phylogenetic analyses based on three mitochondrial markers (16S, COI and Cytb) and a fragment of the nuclear Rag1 gene, show complete endemism of the Western Ghats-Sri Lankan species. Four major groups in this region are identified as: 1 — the Hylarana aurantiaca group, endemic to the Western Ghats; 2 — the Hylarana flavescens group, endemic to the Western Ghats; 3 — the Hylarana temporalis group, endemic to Sri Lanka; and 4 — the Hylarana malabarica group from Sri Lanka and India. The discovery of numerous morphologically cryptic Hylarana species in this region further emphasizes the benefits of utilizing an integrative taxonomic approach for uncovering hidden diversity and highlighting local endemism in the Western Ghats-Sri Lanka biodiversity hotspot.

In this study, we investigate species level diversity in the monotypic frog family Micrixalidae, which is endemic to the Western Ghats of Peninsular India. Attempting the first near-complete taxon sampling of Indian dancing frogs from the entire Western Ghats, we use 138 tissue samples collected from 70 localities over the last 12 years for DNA barcoding. Our results of multiple mitochondrial gene (16S and COI) barcoding reveal unexpectedly high species level diversity in the genus Micrixalus. Based on molecular and morphological evidence, we herein describe 14 new species, leading to a more than two-fold increase in the number of known species in this ancient lineage. Additionally, certain taxonomic uncertainties about the status of previously known taxa in this genus are resolved. Micrixalus narainensis and M. swamianus are considered as junior subjective synonyms of M. kottigeharensis, whereas M. herrei is resurrected from synonymy of M. fuscus and confirmed as a valid species. Taxonomic accounts of three species-M. elegans, M. silvaticus and M. thampii-are provided for the first time after their original descriptions. For nomenclatural stability, M. fuscus, M. saxicola and M. silvaticus are lectotypified, and M. elegans and M. kottigeharensis are neotypified. Detailed descriptions, morphological and genetic comparisons, illustrations, data on distribution, and natural history are provided for all species. We also provide the first osteological description of M. fuscus, the type species of the genus Micrixalus, and we report foot-flagging behaviour in a total eight species, including two for which it has been studied previously. Overall, our results highlight the underestimation of true diversity in several amphibian groups of the Western Ghats, suggesting that spatial patterns of amphibian richness and endemism in this region need to be further reexamined.

Despite renewed interest in the biogeography and evolutionary history of Old World tree frogs (Rhacophoridae), this family still includes enigmatic frogs with ambiguous phylogenetic placement. During fieldwork in four northeastern states of India, we discovered several populations of tree hole breeding frogs with oophagous tadpoles. We used molecular data, consisting of two nuclear and three mitochondrial gene fragments for all known rhacophorid genera, to investigate the phylogenetic position of these new frogs. Our analyses identify a previously overlooked, yet distinct evolutionary lineage of frogs that warrants recognition as a new genus and is here described as Frankixalus gen. nov. This genus, which contains the enigmatic ‘Polypedates’ jerdonii described by Günther in 1876, forms the sister group of a clade containing Kurixalus, Pseudophilautus, Raorchestes, Mercurana and Beddomixalus. The distinctiveness of this evolutionary lineage is also corroborated by the external morphology of adults and tadpoles, adult osteology, breeding ecology, and life history features.

A new frog species of the genus Microhyla (Anura, Microhylidae) is described from riparian mid-elevation (860 m asl) evergreen forest in Namdapha National Park, located in the eastern Himalayan state of Arunachal Pradesh, India. The new species can be morphologically distinguished from other congeners by a suite of characters such as adult size, dorsal and lateral colouration and markings, snout shape, foot webbing, and digit tip morphology. Phylogenetically, the new species is more closely related to some of the smallest known members of the genus. It forms a deeply divergent sister lineage to the clade containing members of the Microhyla zeylanica species group that are restricted to Peninsular India and Sri Lanka, and shows sequential relationship with Southeast Asian species M. superciliaris, followed by clade containing M. aurantiventris + M. butleri. The discovery indicates that novel taxa representing distinct evolutionary lineages still remain to be formally described in the genus Microhyla, especially from less explored regions such as the eastern Himalayan forests in Northeast India.

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