About Centropyge vrolikii (Bleeker, 1853)
Centropyge vrolikii (Bleeker, 1853) has a pale greyish to brownish body, with whitish scale centres that darken to black toward the tail. The gill slit and base of the pectoral fin are orange, while the caudal fin and the posterior portions of the dorsal and anal fins have a blue margin. Its dorsal fin contains 14 spines and 15–16 soft rays, and its anal fin has 3 spines and 16–17 soft rays. This species reaches a maximum total length of 12 centimetres, or 4.7 inches.
This angelfish is distributed across the Indo-Pacific region. Its range extends from Christmas Island in the west to Vanuatu and the Marshall Islands in the east, north to Taiwan and south to Lord Howe Island. In continental Australia, it is also found off north-western Western Australia, in the northern sections of Queensland’s Great Barrier Reef, and as far south as the central coast of New South Wales.
Centropyge vrolikii occurs at depths between 1 and 25 metres (3.3 and 82.0 ft). It inhabits lagoons and seaward reefs, and is most frequently found in areas with dense coral growth. It is common on rock or rubble substrates, particularly in locations with rich, varied growth of algae and sponges. This species is largely herbivorous, feeding on filamentous algae, and also consumes sponges. It can change sex from female to male: when no male is present in a harem, one of the females changes sex. Juveniles of the mimic surgeonfish, Acanthurus pyroferus, mimic this angelfish species.
