Blue-green with a yellow mask across the face and a black spot at the rear of the dorsal fin.
To about 38 cm. The adult has a blue-scaled body with yellow scale edges and a gold breast, a mostly blue head with a gold mask around the eyes and a dense net of blue lines on the lower face, bright yellow soft dorsal and tail, and a dark spot low on the rear of the soft dorsal, which is the check. The juvenile is black with six thin white bars curved at top and bottom, blue-edged fins and a dark tail with blue barring, and changes over at roughly seven to twelve centimetres.
Adults are unmistakable. Juveniles share the black-with-pale-bars pattern with the emperor and semicircle angelfish; the barred blue-marked dark tail is the sourced character for this one, and no clean separator from a juvenile semicircle angelfish was found.
Five to thirty metres in coral-rich lagoons, channels and outer slopes, often near caves, solitary or in pairs, with juveniles in shallow inshore algal areas. It eats sponges, tunicates, other encrusting animals and algae.
In the aquarium trade but uncommon in it, and only fish under 20 cm adapt.
Ratings are per location: 1 means found on most dives that look for it, 5 means a handful of records. Where enough dives have been logged the figure is calculated from them; otherwise it is an editorial estimate, and says so. We publish habitat and destination, not the dive site.