Black Widow
These spiders are commonly found in the United States and are known for large webs in dark places like garages, wood piles, outdoor toilets and patio furniture. This spider has a body that is shiny black with a red to orange-red hourglass shape on its back. The widow spider may produce effects ranging from mild redness to a lesion several inches in size with a central puncture site, inner blanching and an outer reddened ring. The bite is often initially painful within 30-120 minutes. Painful cramping can proceed to boardlike rigidity, weakness, difficulty breathing, headache and paresthesias.
Brown Recluse
The brown recluse spider is found in the central and southeastern United States. This spider is approximately 1 inch in length or smaller and is light to dark brown in color. It has a characteristic violin or fiddle shaped marking on its back. These spiders hunt at night and do not like being around people. Brown recluse spiders are best known for causing slowly healing skin ulcers. Poisoning usually produces a painful burning sensation at the bite site within 10 minutes, but can be delayed. One to two hours after the bite, a “bull’s eye” lesion forms, consisting of a blanched ring enclosed by a ring of reddened areas.