American box

The box turtle (Terrapene), or box tortoise is a genus of turtle native to North America (United States and Mexico). The 12 taxa which are distinguished in the genus are distributed over four species. It is largely characterized by having a domed shell, which is hinged at the bottom, allowing the animal to close its shell tightly to escape predators. Box turtles have become popular pets, although their needs in captivity are complex.

http://en.wikipedia.org/wiki/Box_turtle