Alligatoridae — Alligators and Caimans
Species I've seen:
Alligator — Alligators
Alligator mississippiensis
American Alligator
Caiman — Caimans
Caiman crocodilus
Common Caiman
Melanosuchus — Black Caiman
Paleosuchus — Dwarf Caimans
Paleosuchus trigonatus
Smooth-fronted Caiman