Molluscs and crustaceans

Molluscs and crustaceans are invertebrate aquatic animals with soft bodies which are ordinarily enclosed within a protective outer shell. Crustaceans, such as lobsters and crabs, are covered with a flexible, articulated carapace. Other species, such as oysters and scallops, belong to the mollusc family. Some molluscs, notably squid, do not have an outer shell, but have a small internal carapace.