There are three large species of Desmognathus found in Great Smoky Mountains National Park, Seal Salamanders, Black-bellied Salamanders, and Shovel-nosed Salamanders. I'm reasonably confident that this fellow is a Seal Salamander, but it's not inconceivable that I've identified it incorrectly. If you can confirm or deny, please send me email, and please tell me your reasoning.