sclerite

A sclerite (Greek , , meaning "hard") is a hardened body part. In various branches of biology the term is applied to various structures, but not as a rule to vertebrate anatomical features such as bones and teeth. Instead it refers most commonly to the hardened parts of arthropod exoskeletons and the internal s of invertebrates such as certain sponges and soft corals. The term scleritome, used often in paleontology, refers to the complete set of sclerites of an organism, often all that is known from fossil invertebrates.