Like Mira said your photo is of a whipscorpion. Unlike scorpions, the tail cannot sting, but is used as a sensory organ.
These arachnids are carnivorous, nocturnal hunters feeding mostly on insects and millipedes, but sometimes on worms and slugs. They are beneficial because they eat roaches and crickets. They love dark damp places.
The largest species of this order are known as Giant Vinegaroon and can be up to 3" long...so my guess is that is what you have. It gets its name from a spray it can emit from the base of the tail that is 85% acetic acid/vinegar. The pinching mouthparts can produce a painful bite, tho it is unlikely to attack a human.
whip scorpion by: Mira
Looks like the arachnid known as a vinegaroon, or whip scorpion. They aren't true scorpions, and that skinny little whip tail has no stinger.
