Looks like a Centruroides vittatus. This scorpion not considered overly harmful by most entomologists. The sting is extremely painful, and should result in no more than discomfort for a short time. Those with weakened immune systems are far more at risk of having a severe reaction, but overall this is not lethal (I believe there have only been 2 recorded deaths ever attributed to this scorpion, so relatively harmless). I was stung on my toe by this type of scorpion years ago (outside of San Marcos), and although it hurt like nuts, and swelled a bit, it did nothing else to me and I was fine in a few hours. I squished the snot out of that stupid scorpion...he won't have the guts to sting me again! 