My name is Otis Guillebeau. I know snakes. The snake in question is an aberrant Cottonmouth.
Aberrant being the key word. Y'all don't see me on here very often, because I'm so busy. My brother is active on here and he asked me to identify this snake. Sure, there are "typical" colors and patterns on Cottonmouths and most of us who have walked through swampy woods have encountered them. This one appears ridge-backed, and it's quite likely in what we call "opaque", which is a pre-shed skin dullness. I haven't been able to zoom-in to see the pupils of the snake, but let me explain this: ALL SNAKES HAVE ROUND PUPILS - IN LOW-LIGHT CONDITIONS!
Before you fall out of your chair laughing, know this: CATS also have round pupils - in low light conditions! Elliptical pupils simply have a greater opportunity to make the most of the ambient light. Opaqueness due to a pre-shed skin condition reduces the light "felt by the snake". Even without magnification, one can see the snakes thermosensitive labial pit (there's one on each side - between the nostril and the eye.
With very close observation, you can faintly see that Cottonmouth pattern!
Before Otis Guillebeau responded to this thread, I emailed Mr. Whit Gibbons the other day to see if he could help us ID the snake. I sent him the link to this thread, and here is his response.
Your guess is correct. That is an underweight cottonmouth that is basking, possibly to get rid of parasites. Probably will be ready to shed soon, which would affect coloration.
You may already have a copy of SNAKES OF THE EASTERN UNITED STATES, recently published by the University of Georgia Press, has lots of photos and natural history information about all snakes in the region. – whit gibbons