The puff adder (Bitis arietans) is a viper species found in savannahs and grasslands from Morocco and western Arabia throughout Africa except for the Sahara and rainforest regions. It is responsible for causing the most snakebite fatalities in Africa owing to various factors, such as its wide distribution, frequent occurrence in highly populated regions, and aggressive disposition. Like all other vipers, it is venomous. Two subspecies are currently recognized, including the nominate subspecies described here. The snake's typical size is about 1.0 m (39.3 in) in total length (body and tail) and very stout. Large specimens of 190 cm (75 in) total length, weighing over 6.0 kg (13.2 lb) and with a girth of 40 cm (16 in) have been reported. Specimens from Saudi Arabia are not as large, usually no more than 80 cm (31 in) in total length. Males are usually larger than females and have relatively longer tails. Normally a sluggish species, the puff adder relies on camouflage for protection. Locomotion is primarily rectilinear, using the broad ventral scales in a caterpillar fashion and aided by its own weight for traction. When agitated, it can resort to a typical serpentine movement of surprising speed. Although mainly terrestrial, these snakes are good swimmers and can also climb with ease; often they are found basking in low bushes. One specimen was found 4.6 m above the ground in a densely branched tree. (Source: Wikipedia.org, CC BY-SA)