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Description:Under three increasingly greater magnifications, this being the lowest at 183X (see PHIL 10089, 10090), what is depicted here is an unidentified pore located on the dorsal abdomen of a venomous brown recluse spider, Loxosceles reclusa, found inhabiting a Kentucky farm. Note the material surrounding the pore’s orifice, and as the magnification increases, it becomes evident that the material is composed of an unidentified bacterial biofilm. It is not known if these were existing symbiotically upon the spider’s exoskeleton, or if they were pathologic in nature, signifying manifestations of a progressive disease process? See PHIL 10086 for a black and white version of this image.

L. reclusa is sometimes referred to as the “violin” or “fiddle” spider, for on its cephalothorax one will see what appears to be coloration in the shape of these stringed instruments, which is quite evident in the color photograph PHIL 1125, depicting a live specimen.
Although spider bites are common in many parts of the United States, most domestic spiders are not substantially venomous to man. The best known exceptions are widow spiders, i.e., Latrodectus spp., including the black widow L. mactans, and brown spiders Loxesceles spp., particularly the brown recluse, Lox. reclusa. However, cases of arachnid envenomation from the hobo spider, Tegenaria agrestis, are being reported increasingly in the Pacific Northwest.

Sometimes a bite from a brown recluse spider can go unnoticed, or maybe feel as slight as a pinprick. However, usually, after 2–8hrs, there is ensuing severe pain, erythema, and localized tissue necrosis due to the venom’s proteolytic enzymes. See PHIL 6265, and 6266 for images showing the after affects of a L. reclusa bite.

High Resolution: Click here for hi-resolution image (16.42 MB)
Content Providers(s):CDC/ Leah Lowrey, Michael Smith
Creation Date:2007
Photo Credit:Janice Haney Carr
CDC Organization
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Copyright Restrictions:None - This image is in the public domain and thus free of any copyright restrictions. As a matter of courtesy we request that the content provider be credited and notified in any public or private usage of this image.