Texas Parks and Wildlife Department Information on Texas Box Turtles
Box Turtles (genus Terrapene) can be distinguished from other native Texas turtles by having a single hinge at the front of the lower shell (plastron), allowing them to fold it up and close the front of the shell entirely; thus the common name of "box turtle." Box turtles also have a hooked upper jaw ("beak") that is lacking in most other Texas turtles. The only other land turtle in Texas is the Texas Tortoise; it lacks any hinges on the plastron, has a head entirely covered with scales rather than having skin, and has a very rough upper shell (carapace). Male box turtles have red eyes (females yellow or golden), a longer tail with a thick base (females shorted and thinner), and a somewhat concave plastron (females have a flat one).