The spiny softshell turtle is one of the largest freshwater turtle species in North America. They can be distinguished from other turtle species by their carapace. Unlike most other turtles, their shell is soft, flat, and rubbery. The edges of the carapace are pliable with small spines (males have more than females). An adult female's carapace can be anywhere from 7 to 19 inches (18 to 48 centimetres) in length, while the male's is much smaller at 5 to 10 inches (13 to 25 centimetres) in length. The turtle’s nose is long and piglike, and its feet are fully webbed. This helps the spiny softshell turtle swim, since it spends most of its life in the water.