|Description:||Under a very low magnification of only 12X, this scanning electron microscopic (SEM) image depicted a rather ominous scene, for entangled in this brown recluse spider web was the exoskeletal remains of an unidentified insect, which was believed to be an ant. Known as “spider silk”, the strands of silk are produced by the spider’s “spinnerets”, which are glands located in the distal tip of its abdomen. Once the prey has become entangled in the web, the spider will cautiously, though aggressively, approach the prey, subduing it with a neurotoxic bite, which also contains proteolytic, or protein-destroying enzymes, and further enwraps the prey in a web cocoon like the one seen here.|
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.