Raorchestes luteolus

Raorchestes luteolus, sometimes known as the Coorg yellow bush frog, is a small frog of the family Rhacophoridae; males measure 24-29 mm in snout-vent length. Its colour is variable. The dominant form is yellowish brown with light-brownish lines, or light yellowish with discontinuous light-brown lines, but some individuals may be almost golden yellow with only faint spots (Wikipedia, general species account).

It is endemic to the Western Ghats, where it is known only from the state of Karnataka. Males start calling at dusk, first under the leaf litter and then ascending to the vegetation. Call characteristics may differ between populations, in particular between the Sharavathi frogs described as Philautus neelanethrus and the nominal R. luteolus (Wikipedia, general species account).