Green Vine Snake, Oxybelis fulgidus

Green Vine Snake, Oxybelis fulgidus. Photograph taken within the confines of the LaPaz Waterfall Gardens National Park, Alajuela, Costa Rica, February, 2012.  Photograph courtesy of Carol Snow, Del Mar, California.

The Green Vine Snake, Oxybelis fulgidus, is a member of the Colubridae family of North American Racers, Coachwhips, and Whipsnakes. The Colubridae family comprises two-thirds of the world’s snake population with one thousand sixty species placed in two hundred forty-nine genera. Many Colubrids are classified as venomous but very few are considered to be dangerous to humans. There are eleven species in the Oxybelis genus. The Green Vine Snake is also known as the Flatbread Snake and in Mexico as Serpiente de Vid Verde.

Green Vine Snakes have a thin body that appears similar to a growing vine with a bright green color dorsally and a yellowish-green color ventrally. A narrow yellowish-white stripe runs along each side of their body and tail. Their head has an aero-dynamic shape and a prominent pointed nose, resembling a leaf, with a yellowish-green color on their upper lip. Their mouth is very large and extends almost the entire length of their head, and their tongue is also green in color. Green Vine Snakes have binocular vision, meaning that their eyes work together to focus on the same image, helping them identify prey easily.  Their tail is prehensile, allowing them to hold on to branches or vines while reaching for prey. Their long, slender body is approximately 2 cm (0.8 inches) thick and may reach up to 2.0 meters (6.5 feet) in length, with their tail typically accounting for more than one-third of their total length. Slight sexual dimorphism is displayed with females maturing at a slightly larger body size than males. 

Green Vine Snakes are diurnal and highly arboreal, spending most of their life high up in the trees. They are solitary and hunt their prey in a “sit and wait” manner, relying on their appearance to hide among the foliage. They are carnivorous and primarily consume lizards, frogs, birds, small mammals, and eggs. When a mouse or lizard is found on the ground, the Green Vine Snake moves down from the trees and follows the prey a short distance, smelling it carefully. If the snake is content, it bites into the head of the prey, lifting it 20 cm (8 inches) to 40 cm (15.5 inches) from the ground. This prevents the prey from using its physical strength to escape. Green Vine Snakes have two larger upper teeth in the back of their mouth that assist in transferring venom to their prey. Venom is not released instantly, rather, the snake must chew their prey to induce the release of the venom. Once the venom penetrates their wounds, the prey becomes immobilized. Green Vine Snakes then rapidly swallow their prey whole before searching for a resting place, usually at the highest point of a tree. Females lay between 6 to 10 eggs from the end of the dry season to the beginning of the rainy season, typically from September to December. The eggs incubate for approximately 100 days before hatching during the rainy season, from January to April. No records on the mating habits of this species are available, however, it is hypothesized that both males and females have a reproductive cycle that is synchronized to the timing of the rainy and dry seasons. The Green Vine Snake is poorly studied with very limited information available about their lifestyle and behavioral patterns including specific details on age, growth, longevity, movement patterns, diet, habitat use, and reproduction.

Green Vine Snakes inhabit tropical wet, moist, and dry forests. Additionally, they occur in secondary growth forest and forest edges along sandy beaches where there are large populations of lizards, a primary prey item. 

The Green Vine Snake may be confused with the Parrot Snake because they are similar in appearance and possess overlapping ranges. These species can be differentiated visually. Parrot Snakes have green and gold or bronze dorsal scales that are outlined in black, and a thick black stripe that extends caudally from their large, yellow eyes. Unlike the Green Vine Snake, their underside is pale and whitish in color. 

From a conservation perspective, the Green Vine Snake is considered to be of Least Concern due to their wide distribution and presumed large population size. While habitat loss due to the destruction of natural forest occurs throughout much of their range, it is not considered a major threat to this species because they adapt well to secondary growth. While Green Vine Snakes are mildly venomous, Extreme Caution should be used if encountered. Their venom is not fatal to humans, but it typically induces a numbness or tingling sensation. Occasionally, their venom may trigger severe allergic reactions.