We got them, mostly found around creek bottoms around here.Copperhead, I don’t think we have them out here; I’ve never seen one. We do have tons of Western Diamondbacks, massasaugas, and Pygmy rattlesnakes.
Edit: from OKsnakes, the range of broadbanded copperheads is most of Caddo county and the north half of Comanche county. I still have never seen one out here
http://www.oksnakes.org/