This is an emerald tree boa (Corallus caninus) – or at least, it was when this was taken back in 2005. In 2009, herpetologists suggested that there was a separate species from a different geographic area, so this one might have changed taxon then when I wasn’t there to witness it.
I would certainly like to be getting such pics in “the wild,” but as yet I have not traveled to South America, despite the excessive funds that nature photography brings in. Instead, this was photographed at the North Carolina Museum of Natural Sciences in Raleigh. Emerald tree boas have virtually no other position that they can be found in, but I just liked the textures of the skin. Those pits!