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Although by combining the two things that most people are afraid of I could immediately destroy my cause, I’m going to post about it anyway. Those of you that have had the misfortune of meeting me will probably have heard me ramble on about this species at some point. Either recounting my repeated failure to go out and see it (curse my British passport…) or attempting to convey that it literally looks like a mythical rock dragon.


The spider tailed viper (Pseudocerastes urarachnoides) in the Iranian mountains

Photo credit: Bobby & Laura Bok


The spider tailed viper (Pseudocerastes urarachnoides) is endemic to the Zagros mountains in western Iran. A sparsely vegetated landscape composed of limestone and the mineral gypsum, which gives rise to cracks and cavities where the snake likes to hide. The species was only formally described in 2006 despite the first specimen being collected in 1968. The frankly outrageous tail ornamentation that gives the species its name was originally dismissed as a tumour or a result of parasitic infection – forgivable with only one specimen available. More specimens were collected, and this was later ruled out. The tail is actually used for caudal luring, a process relatively common among snakes, particularly juveniles. This usually involves the end of the tail being strongly contrasted in colour with the body. The tail is wiggled around in front of the head, mimicking a worm or grub, to hopefully lure in the prey. The snake relies on its camouflage to remain hidden before striking out and killing the unsuspecting prey. The spider tailed viper is believed to specialise in eating birds, perhaps a reason why its tail is so elaborate. Check out the video at the bottom to see it in action!