Corallus caninus is one of the most recognisable snakes of the Amazon canopy, adults an intense green crossed by irregular white bars. The young look nothing like them. Litters of live young, typically five to twenty, are born in shades of red, orange or yellow, and the transition to green happens gradually over roughly nine to twelve months.
The usual explanation is habitat. Juveniles are thought to use lower, more open vegetation and forest edge, where warm colours may blend with dead leaves and dappled light, while adults settle into the green of the mid-storey and canopy. The same ontogenetic colour change occurs independently in the unrelated green tree python of New Guinea, a much-cited case of convergent evolution.
The boa's teeth are also unusual. Its front maxillary teeth are proportionally among the longest of any non-venomous snake, an adaptation for driving a grip through plumage before the coils close. They are not fangs and deliver no venom.