Hobo Spider

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Venom - although the bite of the hobo spider is initially painless, the bite can be serious. After 24 hours, the bite develops into a blister and after 24-36 hours, the blister breaks open, leaving an open, oozing cut.When the venom is injected, the victim will experience an immediate redness, which spreads  around the bite. The most common reported symptom is severe headache. Other symptoms can include nausea, weakness, fatigue, temporary memory loss and bad vision. 
Spider Identification - they are brown in color and the adults measure roughly 1/3 to 2/3 inch in body length and 2/3 to 2 inches in leg span.  Males are very different from females in that they have two large mouth parts that look like boxing gloves. Females tend to have a larger and rounder abdomen when compared to males.
Habitat - they can be found anywhere in Washington, Oregon, Idaho, Montana, Wyoming, Utah and Colorado. They rarely climb  and are rarely found  above basements or ground level.