The spider remains in the irregular web constructed in space between objects. The female is shy and nocturnal. Bites to humans usually occur only if comes in contact with the spider's web or if the spider's body accidentally gets pinned against human skin. The poison of the black widow affects the nervous system, causing severe pain in the vicinity of the bite, dizziness, nausea, blurred vision and breathing difficulty. A physician should be contacted immediately.
Fatalities are rare and recovery is usually quick and complete.
It is usually found in structures that contain dry space which is cluttered, undisturbed and contains a supply of insects or related organisms to be used as food for the spiders. Both males and females are poisonous. The color of the brown recluse varies from light tan to a dark brown. With its legs in a normal standing position, the spider covers an area about the size of a quarter. Reaction to the bite varies considerably depending on the amount of venom injected and the victim's sensitivity.