Africa’s diverse environments, from deserts to rainforests, support a vast array of snake species. The continent is home to around 571 snake species, making it a hotspot for reptilian diversity.
Major Snake Families
The snakes of Africa are broadly categorized into several major families, each with distinct characteristics. The Elapidae family includes highly venomous snakes with fixed, hollow fangs located at the front of their mouths. Their venom is primarily neurotoxic, affecting the nervous system. Most elapids are slender with smooth scales and often exhibit active, fast movements.
Another prominent family is Viperidae, known for their hinged fangs that fold back against the roof of the mouth when not in use. Vipers typically have stout bodies, keeled scales, and broad, triangular heads. Their venom is often hemotoxic or cytotoxic, causing tissue damage and affecting blood clotting.
The Colubridae family is the largest and most diverse, encompassing both venomous and non-venomous species, though most African colubrids are harmless to humans. Lastly, the Pythonidae family comprises non-venomous constrictors, some of which are among the largest snakes globally. Pythons kill their prey by constriction, often by inducing cardiac arrest, and typically possess heat-sensing pits to detect warm-blooded prey.
Notable Venomous Species
Africa is home to several well-known venomous snake species. The black mamba (Dendroaspis polylepis) is widely distributed across sub-Saharan Africa in savannas and woodlands. Despite its name, its coloration ranges from gray to dark brown, with the “black” referring to the inside of its mouth. Black mambas are known for their speed, reaching over 12 miles per hour, and their highly potent neurotoxic venom, which can cause rapid paralysis and respiratory failure.
Cobras (Naja species) are easily recognized by their ability to spread a hood when threatened. Species like the forest cobra (Naja melanoleuca) are large, agile snakes found in humid forests of western and central Africa. Some cobras, such as the spitting cobras, can accurately spray venom from their fangs, typically aiming for the eyes, as a defensive mechanism.
The puff adder (Bitis arietans) is the most widespread venomous snake in Africa, inhabiting savannas and grasslands across most of the continent. It is responsible for a significant number of snakebite fatalities due to its wide distribution, camouflage, and tendency to remain still when approached, leading to accidental encounters. Puff adders have a stout body and possess cytotoxic venom that causes severe pain, swelling, and tissue damage. They are ambush predators, often waiting for prey to come within striking distance.
The boomslang (Dispholidus typus) is a highly venomous colubrid found throughout sub-Saharan Africa. This arboreal snake is often bright green in males and brownish or olive in females, blending seamlessly into its tree-dwelling habitat. Unlike many venomous snakes, its fangs are located further back in the mouth, requiring it to chew to inject its hemotoxic venom. This venom disrupts blood clotting, leading to internal bleeding. Despite its dangerous venom, the boomslang is reclusive and will only bite if severely provoked.
Prominent Non-Venomous Species
Africa is home to a variety of non-venomous species that play important ecological roles. African rock pythons (Python sebae) are the largest snakes in Africa, capable of reaching over 6 meters in length.
They are powerful constrictors, subduing prey by coiling around them, causing cardiac arrest. Their diet is diverse, including large rodents, monkeys, warthogs, and even small antelopes. These pythons are found in various habitats, from forests to semi-deserts, often near water sources.
African house snakes (Boaedon species) are common non-venomous constrictors found throughout sub-Saharan Africa, often near human dwellings, which is where they get their name. They are primarily nocturnal and feed on small mammals, particularly rodents, making them beneficial for pest control. While traditionally thought to specialize in rodents, studies suggest they are opportunistic predators, also consuming lizards, birds, bats, and frogs. These snakes are relatively small, typically reaching lengths between 60 to 150 centimeters.
Another non-venomous group includes the African egg-eating snakes (Dasypeltis species). These snakes are highly specialized, feeding exclusively on bird eggs. They possess unique adaptations for this diet, including the absence of teeth and specialized vertebral projections that crush eggs once swallowed. After extracting the contents, they regurgitate the empty shell.
These snakes are arboreal and nocturnal, allowing them to access bird nests when their occupants are less active. Many species of egg-eating snakes exhibit Batesian mimicry, resembling venomous snakes to deter predators.
Habitats and Distribution
Africa’s diverse biomes directly influence the distribution and adaptations of its snake populations. Snakes are found across nearly all habitats, from the arid conditions of deserts to the humid density of rainforests, as well as savannas, grasslands, and mountainous regions.
The arboreal boomslang, for example, thrives in forested areas and bushlands. Ground-dwelling species like the puff adder are prevalent in savannas and grasslands, using camouflage to blend with the terrain. African rock pythons are adaptable, found in various habitats from forests to near deserts, often near water. Prey availability, such as birds for egg-eating snakes or rodents for house snakes, also dictates distribution, often leading them to areas with abundant food, including human settlements.