Green tree pythons were once known by the name Chondropython viridis and was placed in its own genus. When scientists noticed the similarities with Australian and New Guinea carpet pythons, it was placed in the genus Morelia and given the scientific name Morelia viridis. In the pet trade, however, green tree pythons still go by the nickname “chondro” and this is unlikely to change soon.

There can be considerable variation in color and patterning in green tree pythons. Because of this, some herpetologists and many hobbyists in the pet trade separate the species into variants or races. These include the Aru, Sorong, Biak, and Yapen. While these races aren’t recognized currently, additional research may suggest these variations warrant subspecies or species status.

Green tree pythons are often mentioned in discussions of convergent evolution in reptiles. This is because Morelia viridis shares similar ecology and morphology with emerald tree boas, despite their relatively distant common ancestry. Both species live in tropical rain forest habitats and are arboreal ambush predators. They exhibit similar diets and switch from a diurnal lifestyle as juveniles to a nocturnal lifestyle as adults. Green tree pythons and emerald tree boas also share the same resting and hunting postures and, remarkably, both species undergo ontogenetic color change from a red or yellow juvenile to a bright green adult. This can make it quite difficult to differentiate between the two species. One of the few ways to tell them apart is the position of the labial pits. In emerald tree boas, the pits are on the upper and lower lip. Green tree pythons only have labial pits on the upper lip surface. Emerald tree boas are found in the tropical rainforests of South America.