Smallest viper

The world's smallest species of viper is the Namaqua dwarf adder Bitis schneideri. Native to a limited stretch of coast shared between Namibia and South Africa, it averages 18–25 cm in length, with a maximum reported length of 28 cm. Although its bite is extremely painful, its venom (which is cytotoxic – attacking both cells and tissues) is not known to be fatal to humans. However, there is no antivenom presently available to counteract it.