This is a fairly large river turtle. Females average about 30 cm (12 in) in length and weigh on average around 3 kg (6.6 lb), although large females can measure up to 40 cm (16 in). Males' maximum size is 29.5 centimetres (11.6 in). The northern red-bellied turtle is the largest recorded basking turtle in the Chesapeake Bay region. It is endemic to the United States. The current range of the red-bellied turtle includes a population in Massachusetts, the Plymouth red-bellied turtle, which was previously considered a distinct subspecies (Pseudemys rubriventris bangsi) as well as the coastal areas of New Jersey, Pennsylvania, Delaware, Maryland, Virginia and North Carolina.