Musicians in the marsh: a new species of music frog (Anura: Ranidae: Nidirana) from Arunachal Pradesh, India

We describe a new species of ranid frog of the genus Nidirana from northeast India based on morphological, molecular and acoustic evidence. The new species is phenotypically distinct from its congeners by a combination of morphological characters: body robust with SVL 46.5-59.1 mm (n= 3) in adult males and SVL 60.6-66.0 mm (n= 2) in adult females; a pair of subgular vocal sacs and two patches of nuptial pad on the first finger in adult males; toe tips slightly dilated and oval; circum-marginal grooves present on all toes; dorsal skin with scattered small tubercles. A pale cream-coloured mid-dorsal line from the snout tip to the vent is present. Phylogenetically, the new species differs from its congeners by a genetic divergence of 3.4-8.0% and 7.7-12.4% in 16S and COI genes respectively. Furthermore, the new species can be differentiated from its congeners by its advertisement call, which consists of two different types of notes, call duration (0.58-0.92 s) and dominant frequency of the call (473.7 Hz). The discovery of a new species validates the presence of the genus Nidirana from India and emphasizes the importance of exploring specialized habitats such as marshlands, which are often overlooked.