The family Boidae consists of boas and pythons, boas comprising the sub-family Boinae.
Some herpetologists place boas and pythons in separate families.
Pythons are found in the Old World, Boas are found in the New World, with one exception. The Madagascar Ground Boa is found on that island off of Africa. Different species of boas are found in Western United States through Argentina. Habitats include deserts, plains, forests and tropical rain forests. Heavy-bodied snakes are predominantly terrestrial.