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.

The pit viper snake genus Trimeresurus Lacépède, 1804 sensu lato, is a diverse group of nocturnal serpents comprising over 61 species. The genus is morphologically heterogeneous and has been divided into several subgenera. We present an updated phylogeny of Asian pitvipers and propose a revised classification. Additionally, we revise the taxonomy of T. popeiorum Smith, 1937 and propose taxonomic changes with support from molecular and morphological data. We restrict T. popeiorumsensu stricto to northeastern India, Bangladesh, southern China, and northern Myanmar; populations beyond these areas require further assessment. We also synonymize T. yingjiangensisChen et al., 2019 with T. popeiorum based on overlapping morphological characters, molecular data, and distribution. The findings shed new light on the taxonomy of T. popeiorum, warranting the need for assessing the population of T. popeiorum from southeast Asia.

The gekkonid lizard genusHemidactylusOken is the second most species-rich genus of geckos with greatest diversity in the tropical regions of the world. Some species of the genus are commensal and widespread; however, there are several endemic lineages with restricted distribution. India is home to at least 35 species, with 20 endemic species and the number is steadily increasing with exploration of new habitats and integrated taxonomic approach including molecular data. We made investigations into the molecular and morphological variation throughout the distribution ofHemidactylus triedrusDaudin, 1802 based on fresh specimens, literature review, museum material and molecular data. Results from morphological, molecular and micro-CT based anatomical data are unequivocal and show thatH. triedrusis a species complex represented by three species,H. triedrussensu stricto and two undescribed taxa.H. subtriedrusJerdon, 1854 syn. nov. was found to be morphologically similar to the type specimen ofH. triedrus, and genetically embedded in a clade containingH. triedrussensu stricto and is here treated as a junior synonym ofH. triedrus, whereasH. lankaeDeraniyagala is referred to asnomen dubiumgiven that the types are presently not traceable and the original description is inadequate in diagnosing the taxon. The populations from western-central India and parts of Pakistan, and from southern Karnataka are distinct and diagnosable, and are herein described as two new species, respectively. Morphological and molecular data support the distinctiveness of the new species. The present work resolves a taxonomic turmoil that lasted over two centuries highlighting the need for studies that integrate morphological and molecular data.

Calotes versicolor Daudin, 1802 is one of the most widespread agamid lizard species which was described without a locality. The type specimen of the species has long been considered lost; however most workers considered Pondicherry as the type locality for the species. Studies by Zug et al. 2006 confirmed that C. versicolor is a complex of multiple species which necessitates fixing type locality and specimen for the species in order to resolve the systematics of the species complex. An adult male from Pondicherry was collected and is here designated as the neotype. A re-description of the species is provided along with notes on systematics of the species.

We here describe a new species of bent-toed geckos from the northeastern Indian state of Arunachal Pradesh, which is widespread across the Dafla and Mishmi hills, occurring at elevations ranging from 179 m to 1400 m. The new species is recovered as sister to the Cyrtodactylus khasiensis clade based on a molecular phylogeny inferred from mitochondrial NADH-ubiquinone oxidoreductase, subunit 2 gene. Intraspecific uncorrected pairwise sequence divergence (p-distance) for the new species was found to be between 0 and 5%, whereas the interspecific divergence from the closely-related congeners was between 19 and 30%. The new species can be differentiated from members of the C. khasiensis clade using a suite of morphological characters: moderate body size (SVL 64.9–81.7); 8–11 supralabials; 8–10 infralabials; 24–26 bluntly conical, feebly keeled dorsal tubercles; 50–60 paravertebral tubercles; ~38 ventral scales between ventrolateral folds; no precloacal groves; 6–10 precloacofemoral pores in a continuous series; 10–16 distal subdigital lamellae on IV of pes; subcaudal scalation of original tail without enlarged plates. This is the fourth reptile species described from Arunachal Pradesh from the expedition led by the team, and this further highlights the need for further herpetological investigations into the region.

A new species of bent-toed geckos of the genus Cyrtodactylus is described from western Arunachal Pradesh. The new species is a member of the Indo-Burma clade and is embedded within the “peguensis” group, a relationship deduced contingent on a partial fragment of mitochondrial NADH subunit 2 gene. Cyrtodactylus kamengensissp. nov. is morphologically similar to C. himalayicus from which it differs in bearing a distinct ventrolateral fold and 6–8 basal lamellae on digit IV of pes. Genetically, the new species is sister to the Indian lineage of the “peguensis” group containing C. bhupathyi and C. gubernatoris. The Indian lineage of the “peguensis” group diverged from its Burmese relatives during the mid-Oligocene likely followed by the beginning of the Himalayan uplift, highlighting the role of the Himalayas in the diversification of biota.