High Quality Content by WIKIPEDIA articles! An Alligator is a crocodilian in the genus Alligator of the family Alligatoridae. The name alligator is an anglicized form of el lagarto the Spanish term for "lizard", the name by which early Spanish explorers and settlers in Florida called the alligator. There are two living alligator species: the American alligator (Alligator mississippiensis ) and the Chinese alligator (Alligator sinensis ). There are many adaptations for the American alligator. Baby alligators have an egg tooth that helps them get out of their egg during hatching time. They also have a muscular flat tail that propels them forward while they swim.