REdRUM said:
There's brown recluses up here...and they suck. Ass. Bad.
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In Nevada? I dont know, they are indegenous to the South East of the US, not the West. Ther are otehr spiders that look very similar to Brown Recluses though.
http://en.wikipedia.org/wiki/Brown_recluse
http://en.wikipedia.org/wiki/Image:Distribution.loxosceles.reclusa.png
Also, they rarely actually bite either:
"As indicated by its name, this spider is not aggressive and usually bites only when pressed against human skin, such as when tangled up within clothes, bath towels, or in bedding.[5] In fact, many wounds that are necrotic and diagnosed as brown recluse bites can actually be Methicillin-resistant Staphylococcus aureus (MRSA). Actual brown recluse bites are rare. Brown recluse bites may produce a range of symptoms known as loxoscelism. There are two types of loxoscelism: cutaneous (skin) and systemic (viscerocutaneous).
Most bites are minor with no necrosis."