Hermit Crab

Hermit crabs are anomuran decapod crustaceans of the superfamily Paguroidea, comprising more than 800 species that have adapted to occupy empty, scavenged gastropod shells to protect their soft, uncalcified abdomens. Because their abdominal exoskeleton offers little protection on its own, they depend on shelter produced by other organisms, a dependence that has shaped their biology and let them diversify across nearly every marine environment. Most species develop through metamorphosis, from symmetric, free-swimming larvae into the asymmetric, shell-seeking, bottom-dwelling adults characteristic of the group.