Terrapene nelsoni, Stejneger 1925 (spotted box turtle)

Known from only a handful of localities in the Sierra Madre Occidental of western Mexico, the Spotted Box Turtle, Terrapene nelsoni (Family Emydidae), remains one of the least known chelonian species of North America. Only at the type locality and at one site in Chihuahua have more than four specimens been recorded, most other records consisting of incidental finds or acquisition of solitary specimens. Population density, natural history, and reproductive parameters are thus not understood, and even the favored microhabitat of the species is uncertain.