Raorchestes glandulosus

Raorchestes glandulosus, the glandular bush frog, also called the rough-skinned bush frog or southern bubble-nest frog, is endemic to the Western Ghats and known from Karnataka and Kerala. Males are 22-27 mm in snout-vent length. The snout is pointed, and the colouring of the back varies between individuals and conditions from dark green to dark purple or violet (Wikipedia, general species account).

Its distinguishing feature, at least among the Raorchestes of the Western Ghats, is the yellow back of the forearm and yellow loreal region. The sides, forelimbs and tympanic region are yellow too, and the underside is yellow to light yellow (Wikipedia, general species account).