Worldwide there are 3700 species of snakes, 600 of these are known to be in Africa.
Approximately:

• 120 of them are “front fanged” and are considered the really dangerous snakes of Africa
• 55 African vipers and about 20 burrowing asps, which have long folding fangs
• 40 species are in the Elapide family with short rigid fangs. (Cobras, Mambas, Garter Snakes and Allies)
• 15 rear fanged snakes that have toxic venom and grooved fangs at the back of the upper jaw
• 2 large pythons in Africa
• A handful of them are fangless
• The remaining are harmless to humans