The Arizona Brown Spider is a very nasty critter indeed. Bites from these spiders can produce tissue death. While fatalities are uncommon, the reactions to these bites are quite painful and provide long lasting side effects.
This spider is typically found in cracks of walls, houses, and other buildings. They can also be commonly found underneath rocks.
If you suspect that you have seen these nasty spiders, it is encouraged that you spray regularly to reduce the possibility of colonization.