Nerodia Taxispilota
...has many common names, including the following: aspic, brown water snake, moccasin, pied-bellied water snake, southern water snake, water moccasin, water pilot, and water rattle (or rattler). Few outside the fields of scientific or amateur herpetology refer to N. taxispilota as the brown watersnake.
Nerodia Taxispilota are found throughout the Coastal Plain and into the Piedmont along major rivers from eastern Alabama to eastern Virginia and have been reported from saltwater and brackish waters... Whether the range of this species is expanding or contracting in certain areas remains uncertain and is in need of further study.