The brown recluse spider or violin spider, Loxosceles reclusa, Sicariidae (formerly placed in a family 'Loxoscelidae') is a spider with venomous bite.
Brown recluse spiders are usually between 6-20 mm, but may grow larger. While typically light to medium brown, they range in color from cream-colored to dark brown or blackish gray. The cephalothorax and abdomen may not necessarily be the same color. These spiders usually have markings on the dorsal side of their cephalothorax, with a black line coming from it that looks like a violin with the neck of the violin pointing to the rear of the spider, resulting in the nicknames fiddleback spider, brown fiddler or violin spider.

Loxosceles reclusa; the Brown Recluse Spider is one nasty arachnid to avoid. Its venom contains the potent tissue-destroying dermonecrotic agent, sphingomyelinase.
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