Louis Agassiz described Cistudo ornata in 1857 “from the Upper Missouri … and from Iowa” the type locality was restricted to “Council Bluffs [Pottawattamie Co.], Iowa.” In 1891. Baur resurrected Merrem’s genus Terrapene for the box turtle.
However, the species was based upon syntypes collected from several localities including Yellowstone, Kansas, Illinois, and Iowa. Smith and Ramsey (1952) described the southwestern populations as the subspecies Terrapene ornate luteola, resulting in the eastern populations being called T. o. ornata and the common name Desert Box Turtle or Desert Grassland Box Turtle was applied to this subspecies.
Morphology that distinguished the western subspecies included: 10 to 16 yellow streaks on the second pleural scute. The length of the anterior lobe of the plastron was 69-72% of the length of the posterior lobe. The gular and the pectoral scute lengths are 46-55 and 32-36% respectively, of the anterior lobe length. The carapace ground color is lighter than that of ornate and there is a tendency for the shell of older individuals to become uniformly straw- or horn- colored.
Martin et al. (2013) used molecular data that indicated that T. ornata ornata and T. o. luteola lack distinction phylogenetically and should not be recognized. Herrmann and Rosen (2009) suggested maintaining the subspecies. They examined genetic differences within the Desert Grassland Box Turtle and found relatively slight but consistent differentiation between the subspecies, in mtDNA and no strong differentiation between them in a limited sample of available microsatellite markers. Their results suggest there may be hybridization within the captive population in Tucson. They also failed to successfully identify local genetic variation among Ornate Box Turtle samples from southeastern Arizona.
In Arizona, Ornate Box Turtles mainly inhabit semidesert grassland, but can also be found in Chihuahuan desertscrub, Madrean evergreen woodland, and Sonoran desertscrub (up to 7100 feet in elevation). They require loose soil for burrowing. Terrapene o. luteola is a species of conservation concern in Arizona.
Plumber (2014) found Arizona Ornate Box Turtles live in well-defined home ranges, which included the stock tank and overlapped with home ranges of other turtles. Turtles moved 135 m daily in home ranges averaging 9.8 ha and 469 m across greatest axis. Turtles typically returned to the burrow from which they began their daily movements. There were no sexual differences in daily movement or home range size, nor were there annual differences in daily movement among individuals. Some turtles (seven of 11) made temporary long-distance movements averaging 1,066 m away from their home ranges. Six of 11 turtles exhibited significant directionality in their movements relative to the stock tank.
Since I moved to Arizona in 2014, I have been on the look out for the species, I observed them in Cochise County, at a well know location for them; but I have not been able to locate them in Pima County. In 1958, a few specimens were collected and placed in the University of Arizona’s herpetology collection and at least one paper reports them from the Santa Rita Mountains but provides no details. The observation confirms that the Ornate Box Turtles is still present in eastern Pima County despite concerns for its survival.
In arid environments these turtles spend about 8 to 10 weeks each year above ground – the rest of the year they are subterranean. This week I was driving on a busy highway between a railway line and an active agricultural operation and observed one of the turtles on the edge of the highway, it was an adult male with its red eyes and deeply concave plastron. It may have been the exceptional monsoon that we received this year – more than 14 inches (355 mm) of rain that resulted in the turtles being more active compared to the previous years.
Literature cited
Baur G. 1891. American box-tortoises. Science (426):190-1.
Herrmann H, Rosen PC. 2009. Conservation of aridlands turtles III: preliminary genetic studies of the desert box turtle and yaqui slider. Sonoran Herpetologist. 22(4):38-43.
Martin et al. (2013). Sequence-based molecular phylogenetics and phylogeography of the American Box Turtles (Terrapene spp.) with support from DNA barcoding. Molecular Phylogenetics and Evolution 68: 119–134).
Plummer MV. Spatial relationships of the desert box turtle (Terrapene ornata luteola) captured at a stock tank in southeastern Arizona. Herpetological Conservation and Biology. 2013;9(1):156-62.
Smith HM and LW Ramsey. 1952. A new turtle from Texas. Wasmann Journal of Biology 10:45-54.
