OK, time for another quiz snake. I photographed this at a reptile expo. It is from the US, but what is it?
You could probably cheat but try to get it without it. I didn't guess what it was when I saw it. The snake appeared just as it looks in the photo.

If you want to guess, please don't put the answer in the subject line so others can have a chance.
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Chris Harrison
San Antonio, Texas

