It is a map turtle of some type. Graptemys sp. It is hard for me to distinguish between two possible species Graptemys kohni (Mississippi Map Turtle) and Graptemys pseudogeographica (False Map Turtle). I've heard where they overlap they hybridize (breed between species). Here in KY we have False Maps. I've seen baby MS maps and they look similar to the turtle you have.
ITS A MAP TURTLE. YAAY!
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14 Leopard Geckos 5.9.0
2 Tokay Geckos 2.0.0
1 Graybanded Kingsnake 1.0.0 (on vacation in my house)
1 Baird's Rat Snake (Thanks Vadoni!) 1.0.0
1.0 Ambystoma tigrinum
0.0.1 Leopard Gecko Egg Cookin!