With a top speed of about 12 mph, this deadly African snake is said to be the world's fastest serpent
It is the fastest land snake in the world, and the longest species of venomous 
snake in Africa and the second longest in the world, said Sara ... a top killer in a 
land where nearly 20,000 people die from snake bites every ... one of the fastest 
species of snakes, reaching slithering speed up to 12 mph [19 kph].