Boinae Calabariinae[a] Candoiinae[b] Erycinae Sanziniinae Ungaliophiinae The Boidae, commonly known as boas or boids,[3] are a family of nonvenomous snakes primarily found in the Americas, as well as Africa, Europe, Asia, and some Pacific islands.

The quadrate bones are also elongated, but not as much, while both are capable of moving freely so when they swing sideways to their maximum extent, the distance between the hinges of the lower jaw is greatly increased.

Nearly all have a relatively rigid lower jaw with a coronoid element, as well as a vestigial pelvic girdle with hind limbs that are partially visible as a pair of spurs, one on either side of the vent.

While this is true of boine boas, other boid species are present in Africa, much of southern Eurasia, Madagascar, New Guinea, and the Solomon Islands, so this is not accurate.

The speed with which the coils are applied is impressive and the force they exert may be significant, but death is caused by suffocation, with the victim not being able to move its ribs to breathe while it is being constricted.

[9] The taxonomy of boid snakes has been long debated, and ultimately the decision whether to assign a particular clade to a particular Linnaean rank (such as a superfamily, family, or subfamily) is arbitrary.

Two of them (Tropidophis and Trachyboa) are actually more closely related to the American pipe snake (Anilius scytale) than to the boas, and are now placed in the family Tropidophiidae within the superfamily Amerophidia.