Heniochus chrysostomus, also known as the Pennant Bannerfish, is easy to recognised by its colouration. They are known from the whole western and southern Pacific. From Western India to Pitcairn Islands, north to southern Japan, south to Rowley Shoals, southern Queensland, and New Caledonia; throughout Micronesia.
The Pennant Bannerfish is white with a black band crossing the head and extending through the ventral fins. Two brown bands cross the body. The snout is yellow- gold, stoma. The fourth dorsal fin spine supports an expanded pennant.
Heniochus chrysostomus is found in coral rich areas in subtidal reef flats and lagoons and seaward reefs at depths of 2 to 20 m. Juveniles solitary and usually found in estuaries and lagoons; adults usually in pairs.