Chien Lee / Ecuadorian Toad-headed Pit-viper (Bothrocophias campbelli) in rainforest, Mashpi Amagusa Reserve, Pichincha, Ecuador

Chien Lee / Ecuadorian Toad-headed Pit-viper (Bothrocophias campbelli), Mashpi Amagusa Reserve, Pichincha, Ecuador

Chien Lee / Ecuadorian Toad-headed Pit-viper (Bothrocophias campbelli) camouflaged in leaf litter, Mashpi Amagusa Reserve, Pichincha, Ecuador

Lucas Bustamante / Ecuadorian toadheaded viper (Bothrops campbelli) portrait, Mindo, Pichincha, Ecuador.

Lucas Bustamante / Ecuadorian toadheaded viper (Bothrops campbelli) curled up, Mindo, Pichincha, Ecuador.

Lucas Bustamante / Ecuadorian toadhead (Bothrocophias campbelli) with Mosquito (Culicidae) feeding on its head, Mindo, Pichincha, Ecuador.

Pete Oxford / Amazonian Toadheaded Pitviper (Bothrocophias hyoprora), native to South America

Pete Oxford / Toadheaded Pitviper (Bothrocophias microphthalmus), native to South America

Pete Oxford / Toadheaded Pitviper (Bothrocophias microphthalmus), native to South America

James Christensen / Ecuadorian Toad-headed Pit-viper (Bothrocophias campbelli) eye and pit sensory organ, Mindo, western slope of Andes, Ecuador

James Christensen / Ecuadorian Toad-headed Pit-viper (Bothrocophias campbelli) held up by photographer's assistant, Shannon Bowley, Mindo, western slope of Andes, Ecuador

James Christensen / Ecuadorian Toad-headed Pit-viper (Bothrocophias campbelli), Mindo, western slope of Andes, Ecuador