Bothrops asper

The terciopelo (Bothrops asper) is a species of pit vipers, found from north-east Mexico to northern South America. At low to moderate elevations, its habitat ranges from northeastern Mexico to Colombian and Ecuadorian Andes, as well as Venezuela. With a mass of up to 6 kilograms (13 lb), and a maximal length of 2.5 metres (8.2 ft), the terciopelo is among the largest vipers. It is light to dark brown in color, often with yellowish, zig-zag patterning on either side of its body. Dubbed "the ultimate pit-viper" for its defensiveness, large size, fangs and potent venom yield, it has a fearsome reputation, responsible for the most envenomated snakebites within its range, largely due to its proximity to humans, livestock and pets. Nonetheless, like all venomous snakes, the terciopelo actively avoids contact with humans and larger animals, with bites generally only occurring when the snake is cornered, pursued, or threatened. No subspecies are currently recognized.