Fossils of P. nelsoni have also been found along the coast of South Carolina from the Pleistocene Epoch, indicating that the historic range of this species used to extend farther north.

It feeds on a variety of aquatic plants including waterweed (Vallisneria and Elodea), duckweed (Lemna and Wolffia), and arrowhead (Sagittaria) species.

It appears to have an intermediate salinity tolerance compared to true freshwater forms and the highly specialized terrapin (Malachemys).

The Florida red-bellied cooter can be distinguished from other similar turtles by its distinctive red-tinged plastron (belly) and two cusps (like teeth) on its upper beak.

[1][10] The Florida red-bellied cooter is commonly exported for consumption and the pet trade, with about 50% wild caught individuals and 50% captive bred.