The Ouachita Map Turtle appears to have a very limited distribution in Ohio, being found only in the Scioto River and associated oxbows. Differentiating between a Ouachita and Northern Map Turtle can be very difficult, especially if the turtle is not in hand. Pay close attention to the yellow spot behind the eye. On an Ouachita Map Turtle the spot is shaped like a sickle or hockey stick and extends to the top of the head. Also note the two yellow spots below the eye of a Ouachita Map Turtle, one on the upper jaw and one on the lower. LENGTH: Males - 3.5”–5.75”; Females - 5”–10.75”
Text courtesy of the Ohio Division of Wildlife: https://wildlife.ohiodnr.gov/portals/wildlife/pdfs/publications/id%20guides/pub354_Reptiles-opt.pdf