You have an adult male eastern box turtle, T. c carolina. The large growth rings make him look like he may indeed be captive bred. Definitely not an ornate. He looks healthy. I like the intense black background. I see an "I E I" in his shell pattern.
Yeah I'd say T. c. carolina. They are very interesting critters. Make sure you can get him to eat and checked for worms also of you have other boxers or turtles in general keep an eye out for signs of ranavirus.