
Easily identified by the long trailing filament on the rear dorsal fin. Can grow to 23cm in length. Usually observed in pairs feeding on the polyps of soft and hard corals. Their range is from the Red Sea to Australia.

Bannerfish are readily distinguished from other Butterflyfish by their incredibly long, trailing dorsal fin.
They are sometimes confused with Moorish Idols - though from a different family, both fish can look very similar at first glance. On closer inspection, the head shape is very different. The Longfin Bannerfish has a yellow tail but the Morish Idol's is black.
A very striking species with a bright white patch on each side. They are seen in pairs, either feeding on coral polyps or resting, sheltered near the reef.