Nick Garbutt / Juvenile Colombian Red-tailed Boa Constrictor (Boa constrictor constrictor) moving along a barbed wire fence. Unamas Reserve and Ranch, Los Llanos, Colombia, South America.

Nick Garbutt / Juvenile Colombian Red-tailed Boa Constrictor (Boa constrictor constrictor) moving along a barbed wire fence. Unamas Reserve and Ranch, Los Llanos, Colombia, South America.

Nick Garbutt / Juvenile Colombian Red-tailed Boa Constrictor (Boa constrictor constrictor) moving along a barbed wire fence. Unamas Reserve and Ranch, Los Llanos, Colombia, South America.

Nick Garbutt / Dumeril's Boa (Acrantophis dumerili) basking in late afternoon sunshine on forest floor. Berenty Private Reserve, southern Madagascar.

MYN / JP Lawrence / Young Boa constrictor (Boa constrictor) Gamboa, Panama. Meetyourneighbours.net project

Tim Fitzharris / Boa Constrictor (Boa constrictor), Costa Rica

Suzi Eszterhas / Boa Constrictor (Boa constrictor imperator) Northern Costa Rica, Central America

Suzi Eszterhas / Boa Constrictor (Boa constrictor imperator) Northern Costa Rica, Central America

Claudio Contreras / Dumeril's boa (Acrantophis dumerili), captive.

Daniel Heuclin / Red-tailed Boa constrictor (Boa constrictor constrictor) captive from South America

Claudio Contreras / Boa (Boa constrictor), Calakmul Biosphere Reserve, Yucatan Peninsula, Mexico, October.

Claudio Contreras / Boa (Boa constrictor sigma) camouflaged against leaf-litter. Maria Madre Island, Islas Marias Biosphere Reserve, Sea of Cortez (Gulf of California), Mexico, July.