Pennant coralfish
Heniochus acuminatus
Bannerfish
bannerfish
About
Bannerfish are butterflyfish with a long, trailing fin spine that streams behind them like a flag. In this app the group includes the pennant coralfish and the threeband pennantfish.
How to tell it apart
Look for a disc-shaped reef fish trailing one long, whip-like fin filament from its back. This is easy to confuse with the Moorish idol, which looks similar but is not closely related; the long filament sitting further back on a butterflyfish-shaped body is the mark of a bannerfish. Members are told apart mainly by the number and pattern of dark bands on the body.
Appearance
Bannerfish have a flat, disc-shaped body typical of butterflyfish, but with the fourth spine of the dorsal fin stretched out into a long, thin filament. Adults also have a bump or bony ridge above the eyes and on the nape.
Did you know?
The name Heniochus means "coachman" in Greek, because the fish's long trailing fin spine looks like the whip carried by a carriage driver.
Log it in Into the Blue
Describe what you saw and we name it, then keep every species you find in your Oceandex.
