Your native black rat snake was Elaphe obsoleta obsoleta, and is now considered Pantherophis alleghaniensis.

Pantherophis alleghaniensis is comprised of all obsoleta-complex rat snakes found east of the Appalachian Mountains, and the Chattahoochee/Apalachicola Rivers further south. It is has not been broken into any other subspecies, and is not in and of itself considered a subspecies.
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