Three Toed Box Turtle Hatchling

Or, as Scott pointed out, a Gulf-coast Box Turtle.

It is indeed a Three-toed Box Turtle hatchling

It looks like a box turtle hatchling. In your area it's most likely a Gulf-coast Box Turtle or a Three-toed Box Turtle, Terrapene carolina major or Terrapene carolina triunguis. http://www.indianaturtlecare.com/Box%20Turtle%20Subspecies.html

http://en.wikipedia.org/wiki/River_turtle Central American river turtle