There are two distinct types of Emerald Tree Boas. The northern form is found in Guyana and Surinam and is known as the Guyana Shield or northern Emerald Tree Boa. It is the most common emerald tree boa found in captivity. Corallus caninus, commonly called the Emerald Tree Boa, is a non-venomous boa species found in the rainforests of South America. Since 2009 the corallus batesii species is fully recognized and split from the synonymy corallus caninus. Adults Emerald Tree Boas grow to about 6 feet (1.8 m) in length. They have highly developed front teeth that are likely proportionately larger than those of any other non-venomous snake. The color pattern typically consists of an emerald green ground color with a white irregular interrupted zig-zag stripe or so-called "lightning bolts" down the back and a yellow belly. The bright coloration and markings of the Emerald Tree Boa are very distinctive among South American snakes. Juveniles vary in color between various shades of light and dark orange or brick-red before ontogenetic coloration sets in and the animals turn emerald green (after 9–12 months of age). This also occurs in Morelia viridis, a python species in which hatchlings and juveniles may also be canary yellow or brick-red. As opposed to popular belief, yellow juveniles (as in, the Green Tree Python) do not occur in the Emerald Tree Boa. Specimens from the Amazon River basin tend to grow the largest, are much more docile than their Northern relatives and attain lengths of 7–9 feet (2.1–2.7 m), while the overall average size is closer to 6 feet (1.8 m).
Found in South America in the northern region of Colombia, Brazil, and from Venezuela to Suriname and the Guianas within the so-called Guiana Shield. The type locality given is "Americae." The 'Basin' species', as the name suggests, is only found along the basin of the Amazon River, in southern Suriname, southern Guiana, southern Venezuela to Colombia, Peru and Brazil and in the surrounding jungles of the Amazon River. The Emerald Tree Boas's diet consists primarily of small mammals, but they have been known to eat some smaller bird species as well as lizards and frogs. Due to the extremely slow metabolism of this species, it feeds much less often than ground dwelling species and meals may be several months apart. Previously, it had been thought that the primary diet consisted of birds. However, studies of the stomach contents of this species indicate that the majority of its diet consists of small mammals. Juvenile and neonates have also been known to feed on small lizards and frogs, particularly glass frogs.
Adult Emerald Tree Boas typically feed once every three weeks, shed every six months and defecate every two months or so. They need a stable environment in terms of humidity, temperature and ventilation. Humidity needs to be non-condensing (in other words, there should be no water dripping down the sides of the enclosure) and in the 65- to 75-percent range. Among snake collectors, the Amazon Basin Emerald Tree Boa is a more desirable animal of the two different species, due to its impressive size, striking coloration and gentle nature. They make terrific display animals, are dog tame during the day and savage opportunistic feeders at night.
The Emerald Tree Boa is ovoviviparous, with females producing an average of between 6 and 14 young at a time, sometimes even more. Litters exceeding these numbers are extremely rare. Newly born juveniles have a distinctive brick-red to orange coloration and gradually go through an ontogenetic color change over a period of 12 months, gradually turning to full emerald green. Emerald Tree Boas are surprisingly easy to breed in captivity. Many hobbyists have had good success producing litters on a regular basis from just one or two pairs.