The Boomslang, Dispholidus typus, is a large, highly venomous snake native to the forests and savannas of Sub-Saharan Africa. Its common name is derived from the Afrikaans language, where “boom” means tree and “slang” means snake, aptly describing its arboreal nature. This species is classified within the family Colubridae. The snake has garnered a significant reputation for its dangerous bite, even though encounters with humans are rare.
Physical Characteristics and Identification
The Boomslang possesses a slender body, often reaching an average length of 1.2 to 1.6 meters, though some individuals may grow up to 2 meters. A distinctive feature is its head, which is short and has a blunt, egg-like shape that is clearly set apart from the neck. The snake is recognizable by its exceptionally large eyes, which have round pupils and provide excellent eyesight, aiding its predatory lifestyle.
The most striking aspect of the Boomslang’s appearance is its extreme sexual dimorphism, meaning the sexes look very different. Adult males are typically a vivid green, often with black or blue scale edges, though they can also appear in yellow or black patterns. In contrast, adult females are generally less colorful, exhibiting drabber colorations such as brown or grayish-brown. This provides excellent camouflage against tree bark and is a reliable way to distinguish the sexes.
Range, Habitat, and Behavior
The geographical range of the Boomslang is vast, covering a wide array of environments across Sub-Saharan Africa. This snake is strictly arboreal, living predominantly in trees and shrubs, although it will occasionally descend to the ground to hunt or bask. Its varied coloration allows it to blend seamlessly into habitats like lowland forests, scrublands, and wooded savannas.
The Boomslang is a diurnal species, meaning it is active during the day when it hunts for prey. Its diet is specialized, consisting mainly of chameleons, lizards, and small birds, including their eggs and nestlings. This snake is generally reclusive and non-aggressive toward humans, preferring to flee or remain motionless when disturbed. When threatened, a Boomslang may inflate its neck to display the dark skin between its scales before resorting to a bite.
Understanding Boomslang Venom and Danger
The Boomslang is classified as a rear-fanged snake because its venom-injecting fangs are located toward the back of its upper jaw. For the venom to be effectively administered, the snake must open its mouth wide and then bite and hold on, essentially chewing the venom into the target. This unusual delivery mechanism is one reason why bites to humans are rare, as the snake must make a deliberate effort to envenomate.
The venom itself is a highly potent hemotoxin, a type of toxin that primarily targets the circulatory system. This hemotoxic action disrupts the blood’s natural clotting process. The breakdown of clotting factors results in widespread internal and external bleeding, which can manifest as blood seeping from the gums, nose, urine, and stool, or even from minor cuts.
A significant danger of a Boomslang bite is the delayed onset of symptoms, which may not appear for many hours after the initial strike. Initial signs can include a headache, nausea, and sleepiness, but the catastrophic internal bleeding may take four to eight hours to become evident. This delay can lead a victim to falsely believe the bite was not serious, allowing the venom to cause extensive damage before treatment is sought. For a successful outcome, the prompt administration of a species-specific monovalent antivenom is necessary.