Nine-banded Armadillo

Nine-banded armadillos are terrier-sized, insect-eating mammals encased in a bony shell — big plates over the shoulders and rump, nine hinged bands between, and a long tapering tail sheathed in rings of the same armor. They're diggers first and foremost, hunting by smell with the snout to the ground for grubs and beetles, keeping several burrows apiece, and thriving in sandy soil while staying scarce wherever the ground is too hard or too marshy to work. Litters are always identical quadruplets from a single egg, and a startled armadillo can't roll up into a ball the way some of its relatives can, so it bolts for a burrow instead. Native to South America, the species has pushed steadily north over the past century and now reaches Florida and Missouri, stopping roughly where hard freezes become common.