Carcinology is a branch of zoology that consists of the study of crustaceans, a group of arthropods that includes lobsters, crayfish, shrimp, krill, barnacles and crabs. Other names for carcinology are malacostracology, crustaceology, and crustalogy, and a person who study crustaceans is a carcinologist or occasionally a malacostracologist, a crustaceologist, or a crustalogist. The word carcinology derives from Greek καρκίνος, karkínos, "crab"; and -λογία, -logia.