Chaetodon ephippium also known as the Saddled Butterflyfish can be recognised by the large white-bordered black area on the upper side below the dorsal fin. The body is grey with blue-grey stripes across the lower sides. The breast and snout are yellow. Adults have a filament extending from the back of the dorsal fin.
The Saddled Butterflyfish inhabits tropical waters of the Western and Central Pacific; from Sri Lanka and Cocos-Keeling Islands to the Hawaiian, Marquesan and Tuamoto islands, north to southern Japan, south to Rowley Shoals and New South Wales, Australia. Chaetodon ephippium is commonest found in lagoons and seaward reefs to a depth of 30 m, prefer coral-rich and clear water.
Chaetodon ephippium are sensitive for various diseasis.
Butterflyfish are not recommended for reefs as they will pick at or eat a wide variety of corals, fan worms, and other invertebrates. Most Butterflyfish are known to pick at Aiptaisia, a parasitic anemone.
Sometimes difficult to keep. Use a quarantine tank procedure to get it feeding and verify it is healthy before letting it loose in a display tank. Very sensitive to water quality in that it won't tolerate ammonia or nitrite --- even very low levels. Thus, should only be kept in aquaria by people who have their water quality under control and know how to keep it that way, in a well-established aquarium.