Adults (TP): Black, wedge-shaped to triangular band on the front of body. Similar: B. axilaris (black patches in dorsal and anal fin).
Juveniles are dark purple with large yellow patches. They keep near hiding-place such as crevices and overhangs.
Size : 20 cm
Habitat : In coral-rich outer reefs slopes, 5-30 m.
Distribution : Christmas Island to S Japan, Western Micronesia, PNG and GBR.