The Teardrop butterflyfish, Chaetodon unimaculatus, is a butterflyfish of the family Chaetodontidae found in the Indo-Pacific oceans from East Africa (south to Port Alfred, South Africa), to the Hawaiian, Marquesan and Ducie islands, north to southern Japan, south to Lord Howe and Rapa islands, and throughout Micronesia, at depths down to 196.86 ft (60 m). Its length is up to 7.87 in (20 cm).
The teardrop butterflyfish is easily identified by the color pattern of yellow, white and black. The caudal fin is transparent. Juveniles are virtually identical to adults in coloration.
They occur in small groups in reef flats, clear lagoon and seaward reefs, and feed on soft and hard corals, and also on polychaetes, small crustaceans, and filamentous algae. In Indonesia, they are usually seen at moderate depths, usually swimming in small groups. Adults are mainly at depths of 65.62 to 196.86 ft (20 to 60 m).
Reproduction is oviparous, with pairs forming during breeding. Teardrop butterflyfish are monogamous.