Armadillos are small mammals, known for having a bony armor shell. Until as recently as 1995, the armadillo family was placed in the order Xenarthra, along with the anteaters and sloths. The word armadillo is Spanish for "little armored one".
There are around 20 species of armadillo, some are distinguished by the number of bands on their armor. Their average length is about 30 inches, including their tail. Giant Armadillos can grow up to 39 inches and weigh up to 66 lbs. The Pink Fairy Armadillo has an overall length of only 4 or 5 inches. All are native to the Americas. In the US, the sole resident armadillo is the Nine-banded Armadillo, most common in the central southern states, particularly Texas. They range is as far east as Florida and as far north as Kansas, and while cold winters have slowed the expansion of their range (due to a lack of sufficient body fat), they have been consistently expanding their range over the last century due to a lack of natural predators and have been found as far as western Kentucky, and are expected to eventually reach Ohio before the cold winters inhibit their expansion. |
Armadillos are prolific diggers. Many species use their sharp claws to dig for food, such as grubs, and to dig dens. The Nine-banded Armadillo prefers to build burrows in moist soil near the creeks, streams, and arroyos near which it lives and feeds. The diet of different armadillo species varies, but consists mainly of insects, grubs, and other invertebrates. Some species, however, are almost entirely formicivorous (feeding mainly on ants).
Armadillos have poor vision but are not blind.
The armor is formed by plates of dermal bone covered in small, overlapping epidermal scales called "scutes", composed of bone with a covering of horn. In most species, there are rigid shields over the shoulders and hips, with a number of bands separated by flexible skin covering the back and flanks. Additional armor covers the top of the head, the upper parts of the limbs, and the tail. The underside of the animal is never armored, and is simply covered with soft skin and fur.
This armor-like skin appears to be the main defense of many armadillos, although most escape predators by fleeing (often into thorny patches, from which their armor protects them) or digging to safety. Only the South American three-banded armadillos (Tolypeutes) rely heavily on their armor for protection. When threatened by a predator, Tolypeutes species frequently roll up into a ball. (Other armadillo species cannot roll up because they have too many plates.) The North American Nine-banded Armadillo tends to jump straight in the air when surprised, and consequently often collides with the undercarriage or fenders of passing vehicles.
Armadillos have short legs but can move quickly, and have the ability to remain underwater for as long as six minutes. Because of the density of its armor, an armadillo will sink in water unless it inflates its stomach with air (an ability unique among mammals which allows it to swim across narrow bodies of water), which often doubles its size.
Armadillos use their claws for digging and finding food, as well as for making their homes in burrows. They dig their burrows with their claws, only making a single corridor where they fit themselves. They have five clawed toes on the hindfeet, and three to five toes with heavy digging claws on the forefeet. Armadillos have a large number of cheek teeth, which are not divided into premolars and molars, but usually have incisors or canines.
Gestation lasts anything from 60 to 120 days, depending on species, although the nine-banded armadillo also exhibits delayed implantation, so that the young are not typically born for eight months after mating. Most members of the genus Dasypus give birth to four homozygous young (that is, identical quadruplets), but other species may have typical litter sizes that range from one to eight. The young are born with soft leathery skin, which hardens within a few weeks, and reach sexual maturity in 3-12 months, depending on the species. Armadillos are solitary animals, that do not share their burrows with other adults
