Well, without knowing the size(and how old it is), it is tough, but I will go with it being a speck from a probable splendida intergrade zone. Maybe central Texas, or into Oklahoma.
But as you know, this can cover a HUGE area of several states.
BTW, I am totally surprised(as you probably are) that there haven't been more posts here with snakes that have been showing up, being as it is late April now. 
~Doug
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"a snake in the grass is a GOOD thing" 
my website -serpentinespecialties.webs.com

