Found in Mexico and Central America, this snake belongs to the pitviper subfamily, and is closely related to the cottonmouth and copperhead vipers from the southern United States.
They are highly venomous; their bite causes necrosis, hemorrhage and even renal failure; victims who don’t receive any medical attention after a cantil bite are likely to die in a few hours. But these pit vipers prefer to save their venom for their prey. They feed on any small animal they can catch, from birds and frogs to lizards and small mammals.
Unlike fast-moving elapids such as cobras and mambas, the Cantil has a short, heavy body and can’t chase quickly after prey. Instead, it uses a clever trick to lure their victims into attack range. Its tail has a bright yellow or whitish tip, and the snake can move its tail so that it resembles a wriggling worm. Since many of its favorite prey feed on worms, they are tricked into approaching or even attacking the lure, and then the snake can strike and inject its deadly venom on the unsuspecting would-be predator. Although Cantil vipers are not the only snakes that use their tail to trick prey, they are possibly the best known for it. Because of their yellow or white tail, in some parts of Mexico and Central America these snakes are often called “rabo de hueso”, which means “bone tail”, because, since the rest of the snake’s body is dark colored, it looks as if the tail had been stripped of its skin. Other snakes known to use the same hunting technique, called “caudal luring” by scientists, are the North American copperhead, the Australian death adder and the Dumeril boa from Madagascar.