The Bothrops alternatus, known as yarará in Argentina, is a species of snake from the warm and humid regions of South America, found in Brasil, Paraguay, and Argentina. It is a venomous snake whose glands secretes cytotoxic venom which destroy the tissue around the bitten area. There have been reported cases in which amputation of the hand or foot was required due to severely necrotized tissues (gangrene). The Bothrops alternatus is brown with white V-shaped alternating markings that border darker brown patterns and has a triangular head. The adult female can have a maximum length of 1.60 m, with 1.30 m being the average length.