Rhacophorus exechopygus is a species of frog in the family Rhacophoridae. It is found in the Central Highlands of Vietnam and in the adjacent Annamite Range in Laos. Its range may extend into northeastern Cambodia where suitable habitat should be present. The specific name exechopygus is derived from the Greek words exechos (=jutting out) and pygos (=buttocks), referring to the infra-anal projection characteristic of this frog. Its common names are spinybottom tree frog and Tramlap flying tree frog.