The Woodlouse Spider (Dysdera crocata) is a formidable-looking hunter. In Utah, they are often found in damp areas like basements or under landscape timbers, following their favorite food source: the "Roly-Poly."
If you see a Woodlouse spider, it is a direct indicator of two things: moisture and pillbugs.
The Specialist DietThey eat almost nothing but "Woodlice" (pillbugs/sowbugs). They hunt at night, prowling through damp soil and mulch.
The "Moisture Tracker"They crave humidity. If they are inside your Utah home, they will be in the dampest spots—near floor drains, in crawlspaces, or under leaky sinks.
The Silk RetreatThey don't build webs to catch food. Instead, they spin a small, dense silk "tent" or sac in a crack or under an object to sleep in during the day.
Are those fangs dangerous?While they look scary, their venom is not toxic to humans. However, because the fangs are large, a bite can be physically painful (like a sharp pinch) and may cause minor redness.
Why do I have them in my basement?They followed their food indoors. If you have "Roly-Polies" (pillbugs) in your basement, the Woodlouse spiders will follow them.
Do they eat wood?No. Despite the name, they do not eat or damage wood. They are named after the "Woodlice" (bugs) they hunt.
