Naitik G. Patel’s research while affiliated with Wildlife Institute of India and other places

We describe a new species of rhacophorid frog of the genus Gracixalus from northeast India based on molecular, morphological and acoustic evidence. The new species, formally described herein as Gracixalus patkaiensis sp. nov. , is morphologically distinct from other congeners by a suite of morphological characters such as snout-vent length 23.6–26.5 mm in adult males; green dorsum with irregular brown spots; dorsal skin shagreened with numerous spinules; snout shape nearly acuminate in dorsal and ventral view; a prominent dark streak along the cranial margins; white reticulations along lateral side and ventrum distinct in life. Genetically, the new taxon is found to differ from all the recognized Gracixalus species by 4–14.8% divergence in the 16S mitochondrial gene. The discovery confirms the presence of genus Gracixalus from the Indian state of Arunachal Pradesh underlines the importance of biological exploration even in well-known protected areas of India.

Description of an unique breeding behaviour of Duttaphrynus himalayanus from Sikkim.

We present an updated inventory of the reptilian fauna of Dampa Tiger Reserve based on two separate field surveys during March and September 2021. We recorded 33 species of reptiles which is about 27% of the total reptilian diversity recorded from the state. This includes new distribution records for 16 snake species with observations on rare species: Smithophis atemporalis, Smithophis bicolor, and Boiga quincunciata.

A new species of natricine snake of the genus Rhabdophis is described from Northeast India. Morphologically the new species is similar to Rhabdophis himalayanus but it can be distinguished from it by lacking a nuchal groove and nuchal glands, being relatively smaller, and having a distinct neck, ventral, and subcaudal coloration. In overall coloration it resembles R. chrysargos, from which it is distinguished by several aspects of its morphology and genetic differences. The discovery of Rhabdophis bindi sp. nov. reveals that forested regions in the northeastern part of India needs further biological exploration.

The phylogenetic position of Amolops monticola, a cascade frog species known for over 150 years, remains unknown. Yet over the years new taxa have been frequently described in the ambiguously recognised A. monticola species group, based on morphology and presumed phylogenetic affinities. Here we report fresh collections of A. monticola from the Indian Himalayas and clarify its identity with new molecular and morphological evidence. Furthermore, our surveys in the Northeast Indian State of Arunachal Pradesh have led to the discovery of another new species in the A. monticola group from Siang River basin encompassing the Adi hills (historically known as Abor hills). The new species, formally described as Amolops adicola sp. nov., is morphologically distinguished from its congeners by a suite of characters that include adult size, body colouration and markings, skin texture, snout shape, foot webbing and digit tip morphology, in addition to significant morphometric distinctness observed in principal component analysis. Phylogenetically, the new species is recovered as a well-supported sister taxon of A. monticola, based on Bayesian and maximum likelihood inferences as well as Bayesian Poisson Tree Processes (bPTP) species delimitation analysis using 2001 bp of mitochondrial DNA (16S rRNA, cytochrome c oxidase subunit I [COI] and NADH dehydrogenase 2). It differs from other known members of the group by considerable genetic distances in the studied loci: ≥ 4.3% at 16S, ≥ 6.1% at COI and ≥ 7.0% at ND2. The study also shows for the first time the phylogenetic affinities of another Indian member of the A. monticola group, A. kohimaensis. Altogether, the new insights resolve the long-existing enigma surrounding A. monticola and facilitate a better understanding of systematic relationships within the large A. monticola species group. Our findings also emphasise the need for further dedicated studies on the cascade frogs of Northeast India.

Natural body patterns in amphibians are widely used for individual recognition. In this study, we photographed individuals of Amolops formosus for four days of sampling without handling them. We processed 301 photographs of dorsal blotch pattern in HotSpotter software and verified them visually for confirmation. We identified 160 unique individuals of A. formosus based on the images taken in the field, resulting in an abundance estimate of 180 individuals. The success rate in identifying individuals of A. formosus using the HotSpotter software was 94.3%. We tested the effect of image quality and distance on recognition efficiency. Poor image quality reduced the recognition efficiency of the software but with a careful user review it was possible to identify the individual. The difference between using only the software and software plus human confirmation was very small. This protocol is useful for rapid population estimation of frogs with natural body patterns.