Rabid Wolf Spider

Contrary to its ominous name, the Rabid Wolf Spider (Rabidosa rabida) does not carry rabies, nor is its bite harmful to humans. That said, don't provoke one into biting you, because the pain and inflammation will make you wish you hadn't. But this spider is pretty shy (and quick), so don't worry about tangling with it. You can usually observe it from a distance if you stay very still.

Like Hogna antelucana, the Rabid Wolf Spider has excellent eyesight and is a skillful hunter, chasing down its prey with great speed.

Side-note: Reading back over my post about H. antelucana, I had laugh at the fear concerning spiders I expressed at the time. Now they're the main creatures I look for!

The pattern of the median longitudinal band on the dorsal abdomen is a key characteristic for distinguishing this species from others in the Rabidosa genus. 

References:
http://www.fcps.edu/islandcreekes/ecology/rabid_wolf_spider.htm
http://animaldiversity.ummz.umich.edu/site/accounts/information/Rabidosa_rabida.html
http://bugguide.net/node/view/26084