Named a new species in 2006, the spider-tailed viper’s tail resembles a spider. In the 1970s, when scientists came across the reptile, also known as the Iranian spider viper, they believed its tail was a mutation until they saw more horned vipers. It shares similarities with other species, but it is hard to confuse because of its tail. Aside from elaborate tail ornamentation, it has another distinct characteristic: its horned appearance.
Measuring between 19.6 inches (50 centimeters) and 25.6 inches (65 centimeters) in length, it is a moderately sized snake that weighs about 0.5 pounds. The scaly snake is gray or tan and is adept at camouflage. While similar in size, the spider-tailed viper is not the same species as the Persian horned viper, also known as the false horned viper. Belonging to the species Pseudocerastes persicus, it has horns but not a unique tail. The horned adder is another snake that has horns but no spider-like tail.
Part of the genus Pseudocerastes, the spider-tailed horned viper’s lives in western Iran and eastern Iraq, particularly in the Zagros Mountains. Its natural habitat includes rocky and mountainous terrain. The diurnal animal is active during the day.
Like the green tree python, the spider-tailed horned viper is an ambush predator. The snake preys on unsuspecting birds and does it in the sneakiest way possible. “It’s not actually a mutated on this viper’s tail,” Sami Bayly writes in “Philip Bunting’s Exceptionally Interesting Animals”. “It’s an evolutionary adaptation that acts as a fleshy lure to attract prey. The snake mimics the movements of a spider, wiggling its tail about and moving the ‘legs.’ When a bird comes close to peck at the ‘spider,’ the viper springs out and catches its meal.”
Like the rattlesnake rattles, the viper has an elaborate caudal lure (the movement of its tail). That said, it does not work on local birds who have caught on to the viper’s way. Instead, the horned viper will lure a migrating bird, particularly insectivorous birds. Their venom affecting amphibians and not birds, however, might suggest that amphibians are an important food source.
