Just like Pythons, all Boas species fall under the Boidae family. These snakes are all characterized to a greater or lesser extent by the presence of vestigial claws as a remnant of the pelvis, which are often also clearly visible. The long teeth are also one of the characteristics. Most species also have longer front teeth than back teeth. The big difference between Boas and Pythons is that boas are life-giving (ovivipar) and Pythons egg-laying (vivipar). The largest Boa is the Anaconda (Eunectus) that can grow up to 9 meters and there are several species that stay smaller. The most famous Boa is the Boa Constrictor, which must be able to reach a length of 4 meters.

The Boas family can again be divided into a number of types:

Acrantophis, the Madagascar soil boas, represents two species.
Boa Constrictor, the well-known Constrictor group from South America.
Candoia, the Pacific Soil

Corallus, the boomboas from South America
Epicrates, a large family that all comes from South and Central America.
Eryx, the sand boas that also occur in southern Europe.
Eunectus, the anacondas
Exiliboa Placata, an unknown dwarf boa from Mexico
Lichanura, the rosy boas from western North America
Sanzinia, the Madagascar Boomboa.
Tropidophis, dwarf boas with many island forms from the Caribbean.
Ungaliophis, this species with two subspecies, comes from Central America