Brown Recluse Spider

The brown recluse spider is not an established species in Florida, but physicians have diagnosed its bites. Despite these diagnoses, it has been estimated that up to 80% of suspected brown recluse bites are actually misdiagnosed cases of Staphylococcus infection. Unlike the widow spiders, the brown recluse possesses venom based on a protein called Loxosceles toxin, which directly affects contacted tissues rather than the nervous system. The venom can cause tissue necrosis similar to that observed with many infectious bacteria. The absence of brown recluse specimens thought to be responsible for the “bites” makes it impossible to definitively determine the prevalence of the species. Whether or not the brown recluse occurs in Florida is a matter of considerable debate.

The brown recluse spider is recognized by having a dark violin-shaped mark located behind the eyes. There are three pairs of eyes on this species, while most spiders possess four pairs. The brown recluse is a medium-sized spider about 1/4 to 1/2 inch in length.

The brown recluse spider’s natural habitat is along the Mississippi River valley, especially in northwestern Arkansas and southern Missouri. Because it can live in old boxes and furniture, it is easily transported by humans. Specimens of brown recluse spiders have been found in Florida, but there is no indication that it is able to survive and reproduce in Florida’s environment.

The brown recluse spider is a shy species that bites humans when trapped in clothing or rolled onto when people sleep in bed. Persons bitten by the brown recluse usually do not feel pain for two to three hours, although a sensitive person may feel pain immediately. A blister arises around the area of the bite. The local pain becomes intense, with the wound sloughing tissue often down to the bone. Healing takes place slowly and may take six to eight weeks. If the bite of a brown recluse spider is suspected, collect the spider and consult a physician immediately.