Philautus aurantium (common names: Mendolong bubble-nest frog, golden-legged bush frog) is a species of frog in the family Rhacophoridae. It is endemic to Borneo and found in the Mount Kinabalu region in Sabah[1] and Sarawak, Malaysia.[2] Philautus gunungensis is sometimes considered its subspecies, Philautus aurantium gunungensis.[3]
Philautus aurantium are relatively small frogs growing to 30mm in snout–vent length. The body is sand coloured with black spots scattered along flanks, on posterior part of dorsum, and on legs. It has pale orange groin and ventral side of thighs. Tympanum is indistinct.[2]
Its natural habitats are primary montane and submontane forests 750m–1000mm (2,460feet–3,000feetm) asl.[2] Males call from shrubs and small trees 2–4 metres above the ground. It is threatened by habitat loss caused by clear-cutting. It is present in the Kinabalu National Park.