A new species of Nidirana Dubois, 1992 (Anura, Ranidae) from Chongqing Municipality, China.

Background: The Nidirana Dubois, 1992 exhibit a ubiquitous presence in East and Southeast Asia, spanning from Japan west to southern China and from northern Thailand to northern Vietnam and Laos in the south. The taxonomic categorisations pertaining to this genus continue to be a subject of debate, particularly with regard to those species that possess broad geographical distributions. In China, 18 species of Nidirana are currently recognised.

New information: We describe a new species of this genus from south-western China. Mitochondrial 16S and COⅠ gene phylogenetic analyses support the new species as an independent clade nested within the Nidirana. The new species is phylogenetically close to N.yaoica, with a genetic distance of 2.5% from its sister taxon. Morphologically, the new species can be distinguished from congeners by a combination of the following characteristics: males relatively small (SVL 41.8-43.3 mm); lateroventral grooves present on both fingers and toes; relative finger length Ⅱ < Ⅰ < Ⅳ < Ⅲ; tibio-tarsal articulation reaching to the level of the eye or nostril; a pair of external subgular vocal sacs in males; one single nuptial pad on the dorsal surface of the base of the first finger in males during the breeding season; webbing formula I 1/2 - 1 II 1/2 - 2 III 1 - 2½ IV 2 - 1V.