Common snapping turtle (Chelydra serpentina).—Walter Dawn
Either of two species (family Chelydridae) of edible, omnivorous, freshwater turtles found in North and Central America. They are tan to black and have a rough upper shell, a small cross-shaped lower shell, a long tail, and a large head with hooked jaws. Known for their fierceness, they lunge at aggressors and prey and bite them with their powerful jaws. The common snapping turtle (Chelydra serpentina) has a shell 8–12 in. (20–30 cm) long and weighs 10–35 lbs (4.5–16 kg). The alligator snapping turtle (Macroclemys temmincki), the largest freshwater turtle in the U.S., has a shell 16–28 in. (40–70 cm) long and weighs 40–155 lbs (18–70 kg). It lies quietly on the bottom of slow moving bodies of water, luring fishes by means of a wormlike appendage on the floor of its open mouth.