Desert Recluse Spider

Loxosceles deserta

Desert Recluse

Desert recluse spider (Lynette, Flickr.com)

Desert Recluse web

Recluse spider egg sac (Jeffrey Tucker, Bugguide.net)

Desert Recluse

Brown recluse spider (similar in appearance to desert recluse); note fiddle-shaped marking (Mark Dreiling, Bugguide.net)

Identification

  • in Utah, only found in Washington County
  • 1/4 - 1/2 inch long
  • tan to dark brown with darker fiddle-shaped marking on top
  • six eyes arranged in three groups of two

Nesting Habits

  • spin irregularly-shaped webs in undisturbed areas
  • found outdoors in native vegetation, pack rat dens, etc.
  • seldom found indoors

Diet

  • feed on small live insects and occasionally large dead ones

Significance

  • bites can result in a necrotic ulcer that can take several weeks to heal
  • these spiders are rarely encountered indoors

IPM Recommendations

  • Call a physician or go to an emergency room immediately after being bitten or when symptoms develop. Bring the spider if possible for identification
  • Reduce other insects that serve as food.
  • Prune vegetation around buildingsĀ to limit habitat.

Additional Resources:

IPM for Spiders: Integrated Pest Management in Sensitive Environments (University of Nebraska-Lincoln Extension)