Spiders in Utah
Click here to download a PDF of USU Cooperative Extension publication Spidersn-2012
- Utah Top 20 Arachnids: https://utahpests.usu.edu/uppdl/htm/top-20-arachnids
Spiders are arachnids, a group that includes other 8-legged arthropods like ticks, mites, sun spiders, scorpions, and harvestmen (daddy longlegs). There are approximately 621 species of spiders known to occur in Utah (*Allred and Kaston, 1983). Spiders are beneficial predators and the majority of them are harmless to humans. Much fear of spiders results from the few species that can be dangerous to humans, such as the black widow and brown recluse (which does not occur in Utah), and from the many false facts and myths about spiders. The majority of spiders have weak venom and are only capable of harming small prey that they subdue and consume. If bitten by one of these spiders there may be some slight irritation and swelling similar to a mosquito bite or bee sting. The major spider of medical concern in Utah is the black widow.
*Allred, D.M., and Kaston, B.J. 1983. A list of Utah spiders, with their localities. Great Basin Naturalist, April. Vol. 43, No. 3: pp. 494-522.