The oval butterflyfish, red-finned butterflyfish or redfin butterflyfish, is a species of marine ray-finned fish, a butterflyfish belonging to family Chaetodontidae. It is found in the Pacific Ocean from Eastern Indonesia to the Hawaiian islands. This is one species of a closely related group which includes the blacktail butterflyfish, which is found in the Red Sea and Gulf of Aden, and the melon butterflyfish, which is found in the Indian Ocean.

The melon butterflyfish or the Indian redfin butterflyfish, is a species of marine ray-finned fish, a butterflyfish belonging to the family Chaetodontidae. It is found in the Indian Ocean from East Africa to Western Java. This is one species of a closely related group which includes the blacktail butterflyfish of the Red Sea and Gulf of Aden and the oval butterflyfish which is found in the western Pacific, from eastern coasts of the Indonesian islands to Australia.