An immature Emperor Angelfish (fig.), a species of marine reef-fish, of which juveniles look nothing like their adults, and also live separately from them.

Juveniles are dark blue to black, with a pattern of white, vivid blue and yellow lines, that form concentric rings toward the centre rear of the body and become circular spots on the dorsal and anal fins.

Emperor Angelfish are popular aquarium fish, though this may delay or obstruct transition into full adult colouration.