Crotalus durissus is a venomous pitviper species found in South America. The most widely distributed member of its genus, this species poses a serious medical problem in many parts of its range. Currently, nine subspecies are recognized, including the nominate subspecies described here. Grows to a maximum length of about 180 cm (about 6 feet).

Common name. South American rattlesnake, tropical rattlesnake, neotropical rattlesnake, Guiana rattlesnake (previously used for C. d. dryinus).

Spanish: vĂ­bora de cascabel, cascabel, cascabela, cascavel.