Scientists have discovered three new species of cascade frogs from the biodiverse-rich forests of Northeast India and documented five other species in the country for the first time.
Using DNA analyses along with detailed morphological comparisons of adult frogs and tadpoles, the scientists confirmed that populations from Tripura, Nagaland and West Bengal represent three species previously unknown to science. The research, led by Prof. S. D. The newly identified species are Ammachi’s Cascade Frog ( Amolops ammachi ), discovered in the Jampui Hills of Tripura; Sendenyu Cascade Frog ( Amolops sendenyu ), found in Nagaland and named after Sendenyu Village; and Beautiful Cascade Frog ( Amolops bella ), discovered in West Bengal and named for its striking green body marked with yellowish-green or reddish-brown mosaic patterns. It is a taxonomically challenging group but we have now clarified several confusing aspects of its biology, which will help in proper identification and conservation of species. Biju, the lead author.
The findings, published in the peer-reviewed Bulletin of the Museum of Comparative Zoology , are the culmination of over 15 years of extensive field research across the northeastern States. Biju of the Department of Environmental Studies, Delhi University, documented more than 300 geographic populations of cascade frogs inhabiting fast-flowing forest streams. “This study is a work of over 15 years to comprehensively study India’s cascade frogs.
Our study reaffirms that many Indian faunal groups remain poorly studied and contain undiscovered biodiversity, especially in the lesser explored northeastern States that are part of two internationally recognised biodiversity hotspots,” said Prof.
The study also reports five cascade frog species that have never before been recorded from India to expand the known diversity and distribution of the genus Amolops in the country. To reconstruct the evolutionary history of cascade frogs, the researchers employed DNA-based dating analyses. The study suggests multiple waves of colonisation from east to west across Asia and identifies the early uplift of the Himalayas as a key factor shaping the present-day distribution and diversity of these amphibians.
Their results indicate that the frogs underwent extensive diversification around 32 million years ago during the Eocene-Oligocene transition, a period marked by widespread biological turnover.
