Boxfish is a fish with a rigid, box-shaped carapace. The carapace is an outer covering made up of fused plates of bone. The fish’s eyes, mouth, and fins poke through holes in the carapace. Boxfish cannot flex their bodies to swim, as do most fish. Instead, boxfish rely entirely on waving motions of their fins to slowly maneuver in the tight spaces of rocky and coral reefs.
There are dozens of species (kinds) of boxfishes. Some species are also called cowfishes because they have a pair of projections above the eyes that resemble cow horns. Other boxfishes are known as trunkfishes. Boxfishes are closely related to puffers, porcupinefish, and triggerfish. The largest boxfish can grow to 20 inches (50 centimeters) long. Most adult boxfish, however, only reach about 8 inches (20 centimeters) in length.
Boxfish live in and around tropical coral reefs, rocky reefs, and beds of algae or sea grass. They use their forceful jaws to feed on such small animals as crustaceans, mollusks, sponges, and worms. Like many other coral reef fishes, boxfishes are often brightly colored and may have spots. Several boxfishes are known to release highly poisonous slime from their skin when threatened or stressed. This adaptation, together with the strong and often spiny carapace, protects the boxfish against attacks by predators.
