A carapace is a dorsal 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.
In crustaceans, the carapace is a part of the exoskeleton that covers the cephalothorax. The carapace functions as a protective cover over the cephalothorax. Where it projects forward beyond the eyes, this projection is called a rostrum. The carapace is calcified to varying degrees in different crustaceans.
In arachnids, the carapace is formed by the fusion of prosomal tergites into a single plate which carries the eyes, ocularium, ozopores and diverse phaneres.
In a few orders, such as Solifugae and Schizomida, the carapace may be subdivided. In Opiliones, some authors prefer to use the term carapace interchangeably with the term cephalothorax, which is incorrect usage, because carapace refers only to the dorsal part of the exoskeleton of the cephalothorax.
Alternative terms for the carapace of arachnids and their relatives, which avoids confusion with crustaceans, are prosomal dorsal shield and peltidium.
The carapace is the dorsal convex part of the shell structure of a turtle, consisting primarily of the animal’s ribcage, dermal armor and scutes.
Related Sites for Carapace
- Carapace – Definition and More from the Free Merriam-Webster … read Carapace
- carapace – definition of carapace by the Free Online … read Carapace
- Carapace | Define Carapace at Dictionary.com read Carapace
- Carapace – What Is a Carapace – About.com Marine Life read Carapace