Atheris mabuensis, or the Mount Mabu forest viper, is a species of snake

Snake

Snakes are elongate, legless, carnivorous reptiles of the suborder Serpentes that can be distinguished from legless lizards by their lack of eyelids and external ears. Like all squamates, snakes are ectothermic, amniote vertebrates covered in overlapping scales...

 in the Viperidae

Viperidae

The Viperidae are a family of venomous snakes found all over the world, except in Antarctica, Australia, Ireland, Madagascar, Hawaii, various other isolated islands, and above the Arctic Circle. All have relatively long, hinged fangs that permit deep penetration and injection of venom. Four...

 family. It is endemic to Mozambique

Mozambique

Mozambique, officially the Republic of Mozambique , is a country in southeastern Africa bordered by the Indian Ocean to the east, Tanzania to the north, Malawi and Zambia to the northwest, Zimbabwe to the west and Swaziland and South Africa to the southwest...

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During his second reconnaissance visit to Mount Mabu (23–26 January 2006) a very young forest viper was found by Dr. Julian Bayliss in leaf litter on the floor of closed-canopy wet forest on Mount Mabu at approximately 1000m. On examination in the Port Elizabeth Museum (BayWorld, acronym PEM) herpetological collection by Prof. Bill Branch, the specimen was identified as a member of the genus Atheris, which had never previously been recorded from Mozambique and which, moreover, represented a substantial southern range extension for the genus.