Eastern Green Mamba

The eastern green mamba (Dendroaspis angusticeps) is a highly venomous snake species of the mamba genus Dendroaspis native to the coastal regions of southern East Africa. Described by Scottish surgeon and zoologist Andrew Smith in 1849, it has a slender build with a bright green back and green-yellow ventral scales. Adult females average around 2 metres (6 ft 7 in) in length, and males are slightly smaller.

In spite of common urban legends and misconceptions labeling the eastern green mamba an aggressive, fast-moving "people-chaser", it is in fact a shy and elusive species that remains hidden in the trees, and is rarely seen. This seclusion is usually attributed to its arboreal habitat and green colouration, which acts as effective camouflage in its natural environment. Even with its deadly venom, the green mamba has to protect itself from predators, including birds of prey and other snakes, such as cobras. It has been observed engaging in ambush predation, a trait seen among many Viperidae species, contrary to the active hunting style typical of other Elapidae snakes. It preys on arboreal and winged animals, such as birds and their chicks and eggs, bats, and arboreal rodents such as mice, rats, and gerbils.

Eastern green mamba venom consists of both neurotoxins and cardiotoxins. Symptoms of envenomation include swelling of the immediate bite-wound area, dizziness, vertigo and nausea, accompanied by dehydration, labored breathing and difficult swallowing. This eventually will develop into arrhythmia and convulsions—all progressing to respiratory paralysis, which results in a fatal lack of oxygen to the brain. Bites that are severe if not immediately treated on-site can quickly prove deadly.

Taxonomy

The eastern green mamba was first described as Naja angusticeps by Andrew Smith, a Scottish surgeon and zoologist, in 1849, who reported it from Natal and east to Maputo Bay. The specific name angusticeps is derived from the Latin word angustus, "narrow", and ceps, an abbreviated form of caput ("head") when used in a compound word. The German-British zoologist Albert Günther described Dendroaspis intermedius from the Zambezi River in northern Mozambique in 1865. This was subsequently synonymised with D. angusticeps.

In 1896, the Belgian-British zoologist George Albert Boulenger combined the species Dendroaspis angusticeps with the black mamba (Dendroaspis polylepis), a lumping diagnosis that remained in force until 1946, when the South African herpetologist Vivian FitzSimons published a paper after examining approximately 50 eastern green mamba and 85 black mamba specimens. He concluded that the differences in build, scalation, colouration and behaviour warranted splitting them into separate species. The British biologist Arthur Loveridge augmented FitzSimons' work with material from outside South Africa, noting some overlap in scalation but supporting the separation. A 2016 genetic analysis showed the eastern green and black mambas are each others' closest relatives, their common ancestor diverging from a lineage that gave rise to Jameson's mamba (Dendroaspis jamesoni) and the western green mamba (Dendroaspis viridis), as shown in the cladogram below.