Alytes, 2017, 34 (1¢4): 1¢19. A new species of the genus Nasikabatrachus (Anura, Nasikabatrachidae) from the eastern slopes of the Western Ghats, India S. Jegath Janani1,2, Karthikeyan Vasudevan1, Elizabeth Prendini3, Sushil Kumar Dutta4, Ramesh K. Aggarwal1* 1Centre for Cellular and Molecular Biology (CSIR-CCMB), Uppal Road, Tarnaka, Hyderabad, 500007, India. <
[email protected]>, <
[email protected]>. 2Current Address: 222A, 5th street, Annamalayar Colony, Sivakasi, 626123, India.<
[email protected]>. 3Division of Vertebrate Zoology, Department of Herpetology, American Museum of Natural History, Central Park West at 79th Street, New York NY 10024-5192, USA. <
[email protected]>. 4Nature Environment and Wildlife Society (NEWS), Nature House, Gaudasahi, Angul, Odisha. <
[email protected]>. * Corresponding Author. We describe a new species of the endemic frog genus Nasikabatrachus,from the eastern slopes of the Western Ghats, in India. The new species is morphologically, acoustically and genetically distinct from N. sahyadrensis. Computed tomography scans of both species revealed diagnostic osteological differences, particularly in the vertebral column. Male advertisement call analysis also showed the two species to be distinct. A phenological difference in breeding season exists between the new species (which breeds during the northeast monsoon season; October to December), and its sister species (which breeds during the southwest monsoon; May to August). The new species shows 6 % genetic divergence (K2P) at mitochondrial 16S rRNA (1330 bp) partial gene from its congener, indicating clear differentiation within Nasikabatra- chus. Speciation within this fossorial lineage is hypothesized to have been caused by phenological shift in breeding during different monsoon seasons—the northeast monsoon in the new species versus southwest monsoon in N.