Clawed Lobsters compose a family (Nephropidae, sometimes called Homaridae) of large marine crustaceans. The American Homaridae, found living off the eastern coast of North America between Newfoundland and North Carolina in waters as deep 400 fathoms, is also referred to as the Canadian lobster, the Maine Lobster, the Massachusetts lobster or the North Atlantic lobster. There are two basic types of lobsters in the United States. The North Atlantic lives in cold water and has claws and the Spiny lobster lives in warmer waters and has long thorny antennae. Lobsters belong to a major group of invertebrates called arthropods. The characteristics of these animals are a tough exoskeleton with jointed appendages and segmented bodies. They are very similar to crabs, crayfish and shrimp. It will take a lobster five to seven years to grow to one pound.