The black mamba (Dendroaspis polylepis) is a species of extremely venomous snake, a member of the family Elapidae native to parts of sub-Saharan Africa.First formally described by Albert Günther in 1864, it is the second-longest venomous snake after the king cobra; mature specimens generally exceed 2 m (6 ft 7 in) and commonly grow to 3 m (9 ft 10 in).Class: Reptilia. There is no visible difference between a male and female black mamba. An adult snake reaches an average length of 2.5m. The longest black mamba (and current record length), measuring 4.4m, was found in Zambabwe. Unlike popular perception, Donald says the snake is not aggressive and will do anything in its power to head away from humans rather.