You identify a butterflyfish by its boldly colored and sail or disk-shaped body. Butterflyfish are quite distinct in their appearance. They are between 4 and 9 inches (12-22 cm) in length and have round tails, long fins, long snouts, comb-like teeth. Butterflyfish are most commonly yellow, black, white, silver, red, or orange.
These colors may become more vibrant or fade, depending on the time of day and how they are feeling.
Additionally, butterflyfish are can be identified by their unique patterns and the false eyes that protect them from predators.