I've only seen them in far west Texas, Big Bend/Trans-Pecos region. We called them Solfugids or wind scorpions. Caught lots of Vinageroons too those are even cooler. Caught lots of scorpions, scolopendra centipedes, desert millipedes, texas tan tarantulas, black widows, rattlesnakes, ratsnakes, milksnakes, coachwhips, toads and turtles too.
Made for good beer money :D