The head looks very similar to that of other Pseudocerastes species in the region, but the spider-tailed horned viper has a unique tail with a bulb-like end that is bordered by long drooping scales that give it the appearance of a spider.

[6] The specific name, urarachnoides, is derived from Ancient Greek (οὐρά + αράχνη + οειδής), and refers to this snake's spider-like tail-tip, as does the common name, spider-tailed horned viper.

A specimen had been collected in 1968 as part of the Second Street Expedition to Iran and deposited in the Field Museum of Natural History at Chicago, identified as Pseudocerastes persicus.

[11] It overlaps in distribution with P. fieldi in Gilan-e Gharb, next to Qasr-e Shirin, Kermanshah, and with P. persicus in Bina and Bijar, Ilam Province.

The tail resembles a spider or other arachnid, and the authors who described the species speculated that it was used as a lure to attract birds, as a digested lark had been found in the stomach of the paratype specimen.

[4] The tip of the tail is used as a lure in several other species of snake, including the horned adder (Bitis caudalis), sidewinder (Crotalus cerastes), eastern massasauga (Sistrurus catenatus), eastern copperhead (Agkistrodon contortrix), common death-adder (Acanthophis antarcticus), northern death-adder (Acanthophis praelongus), and green tree python (Morelia viridis), but none of these examples has the unique elongated scales that give it the appearance of arthropod appendages.

Footage of the spider-tailed horned viper using its tail to lure a migrating bird featured in the Asia episode of the BBC series Seven Worlds, One Planet narrated by David Attenborough.

There is speculation that the venom affecting amphibians, toads specifically, could be a sign that these are the main diet of the young snakes, though more information about the juveniles still needs to be collected.