North American wood turtle

Wood turtles grow to between 14 and 20 centimeters (5.5 and 7.9 in) in length, and reach a maximum of 23.4 centimeters (9.2 in). They have a rough carapace that is a tan, grayish brown or brown color, with a central ridge (called a keel) made up of a pyramidal pattern of ridges and grooves. Older turtles typically display an abraded or worn carapace. Fully grown, they weigh 1 kilogram (35 oz). The wood turtle's karyotype consists of 50 chromosomes.

The larger scutes display a pattern of black or yellow lines. The wood turtle's plastron (ventral shell) is yellowish in color and has dark patches. The posterior margin of the plastron terminates in a V-shaped notch. Although sometimes speckled with yellowish spots, the upper surface of the head is often a dark gray to solid black. The ventral surfaces of the neck, chin, and legs are orange to red with faint yellow stripes along the lower jaw of some individuals. Seasonal variation in color vibrancy have been known to occur