Its color is a bright green, which allows it to camouflage itself among the dense vegetation. The ventral area has a yellowish color. The scales on the head are small and irregular. It has thermal pits on its upper lip that allow it to detect the heat emanating from its prey. Its tail is prehensile and this helps it climb and hold on to trees.

At birth, the babies can be yellow or red, and measure about 30 centimeters. The red color is less common and only occurs in specimens that populate the jungles in small areas of Papua New Guinea. Between the first and third year of age, they will adopt the greenish color that characterizes them, and which they reach when they mature sexually.