The highly speciose gekkonid genus Cnemaspis Strauch, 1887 is polyphyletic, with three distantly related and geographically isolated clades from Africa, South Asia (SA), and Southeast Asia. At present, there are 85 known species within SA Cnemaspis , although the number continues to increase rapidly with focused surveys and rigorous taxonomic work. Recent studies have provided valuable insights into the diversity and evolutionary history of SA Cnemaspis ; however, most of these studies lack sufficient sampling in the Western Ghats (WG), where the genus has its greatest diversity. We addressed this research gap by conducting extensive sampling across the WG and re-examining museum specimens, thus providing a systematic account of various extant Cnemaspis species along with their distribution and natural history. We described 12 new species and a southern WG endemic clade of SA Cnemaspis. Ten of the newly described species are endemic to the forests of the southern WG. We also identified 10 well-supported subclades that can be separated across morphological, geographic, and phylogenetic axes. A time-calibrated phylogeny and ancestral area reconstructions confirmed the Paleocene origin of SA Cnemaspis in the WG and provide insights into its evolutionary history and biogeography. The discovery of multiple endemic and deeply divergent lineages further highlights the evolutionary significance of the WG for lizards.

The genus Calotes Cuvier, 1817 (Agamidae: Draconinae) is highly diverse, with species occurring in South and Southeast Asia, and Oceania. Most species of the subfamily except C. versicolor have narrow geographic distributions. Calotes versicolor is distributed from western Iran in the west to south China and Indonesia in the east and has been introduced to parts of Africa and North America. The species has had a complicated taxonomic history; multiple species and subspecies related to C. versicolor were described from India and adjoining regions, which were synonymized in subsequent revisions. However, a study of Burmese C. versicolor yielded two new species, C. htunwini and C. irawadi, indicating that C. versicolor is a species complex. Such integrative taxonomic studies have not been carried out in India, the supposed type locality of C. versicolor. Hence, we studied C. versicolor sensu lato from the Indian subcontinent and generated sequences of mitochondrial 16S and COI fragments from tissues sampled from multiple localities in the region, including the type localities of its synonyms. Phylogenetic analyses revealed four well-supported, deeply-divergent lineages, supported by morphological data. These lineages represent (i) C. versicolor sensu stricto, from South India and parts of the east coast, (ii) C. irawadi sensu lato from northeast India and Southeast Asia, (iii) a synonym from the eastern Indo-Gangetic Plains which we resurrect here, and (iv) a subspecies from Pakistan which we elevate to species level. We provide re-descriptions for the resurrected or elevated species, and a diagnostic key to the species of the C. versicolor complex. The study shows that C. versicolor sensu stricto is endemic to parts of southern and eastern India, and not widely distributed, though it may have been introduced to other parts of the world.

We carried out a taxonomic revision of Ahaetulla species inhabiting Peninsular India, using a multiple criteria approach (including genetics, morphology, and geography). Our work included populations of the A. nasuta complex (widespread across the entire region, including the Western Ghats), the A. pulverulenta complex (in the Western Ghats, within Peninsular India) and the A. dispar complex (endemic to the Southern Western Ghats) which all revealed undocumented cryptic diversity. Here, we describe five new species and effect nomenclatural changes to some recognised taxa. In the A. nasuta complex, we describe four species from several latitudinal blocks of the Western Ghats and make nomenclatural emendations to the plains populations in the Indian peninsula. We effect nomenclatural change in the A. pulverulenta population of the Western Ghats and describe a new species from the A. dispar group. Our study highlights the use of a multi-criteria approach in unraveling cryptic diversity. This study also reveals a striking case of discordance between morphological and genetic divergence, and the way this is reflected in previous taxonomic and nomenclatural treatments of these populations.