Boa (genus)

Boa is a genus of snakes in the family Boidae. Four species have commonly been placed in this genus. However three of them ( the Madagascar Ground Boa Acrantophis madagascariensis and the Madagascar Tree Boa Sanzinia madagascariensis and Dumerli's Boa Acrantophis dumerili (also from madagascar) are not considered to be close relatives to first species of the genus to be described, the Red-tailed Boa, Boa constrictor, and thus are often moved to other genera within the subfamily Boinae. All are nonetheless commonly known as "boa constrictors". To add further to the naming confusion, many species of snake in Boidae are known as "boas" and all are constrictors (that is, they kill their prey by constriction). Many subspecies of Boa constrictor have been recognised, and several have distinct common names.
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