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The Yellow boxfish (juvenile) is easy to recognize due to its boxy appearance and the bright yellow body with black spots. Boxfishes secrete a potent toxin (a.k.a. ostracitoxin) from their skin when they are in danger or stressed. Many reef predators will take one taste and spit them out. A juvenile boxfish is about 5-8 cm in length. Adults can grow up to 45 cm. They inhabit coral and rocky reefs and are usually found at depths between 1 and 50 meters. Juveniles are often found between Acropora corals and narrow crevices. Boxfishes feed mainly on algae, but also eat other tiny animals like microorganisms, invertebrates, mollusks and crustaceans. It uses its thick puckered lips to blow jets of water at the sand, exposing hiding animals.