A carapace is a dorsal (upper) section of the exoskeleton or shell in a number of animal groups, including arthropods, such as crustaceans and arachnids, as well as vertebrates, such as turtles and tortoises. In turtles and tortoises, the underside is called the plastron.

The carapace is the dorsal (back) convex part of the shell structure of a turtle, consisting primarily of the animal's rib cage, dermal armor, and scutes.

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