Desert Recluse Spider - School IPM - USU Extension

    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 buildings to limit habitat.

    Additional Resources:

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