Dendroaspis Schlegel, 1848
Mambas, of the genus Dendroaspis (literally "tree snake"), are fast-moving land-dwelling snakes of Africa. They belong to the family of Elapidae which includes cobras, coral snakes, death adders, kraits and, debatably, sea snakes (although sea snakes are now classed as Hydrophiidae). Mambas are feared among their habitats. In Africa, there are many legends and stories describing these snakes.
There are four species plus a number of subspecies of mamba.
* Dendroaspis angusticeps Eastern green mamba
Most of the members in this genus (for example green mambas) are arboreal. However, the black mamba is terrestrial. They are diurnal. During the day, they actively hunt their prey of small mammals, birds, and lizards. They return to the same lair nightly.
Mambas are related to the cobras (Elapidae), as can be seen during their threat display, when they stretch a slightly smaller 'hood' while gaping their mouth.
Many people believe that the black mamba will actually chase and attack humans. This is a myth, and is probably misunderstood by the great speed with which this species can move. The black mamba usually uses its speed to escape from threats rather than for hunting. Humans are actually their predators, rather than their prey. For that reason, mambas generally avoid contact with humans.
Mambas have highly toxic venom which consists mostly of neurotoxins. The bite can be fatal to humans without access to proper first aid and subsequent antivenom treatment as it shuts down the lungs and heart. The Western green mamba (D. viridis) and Eastern green mamba, (D. angusticeps), possess venom that is roughly equal in potency to that of the black mamba. However, they are not nearly as aggressive.
Prior to the availability of antivenom, envenomations by members of this genus carried a high fatality rate. However, with antivenom being much more available today, fatalities have become much more rare.
Mamba toxin is in fact several components, with different targets. Examples are:
* Mamba toxin 3, which inhibits M4 receptors. 
1. ^ The new encyclopedia of Reptiles (Serpent). Time Book Ltd. 2002.
Source: Wikipedia, Wikispecies: All text is available under the terms of the GNU Free Documentation License