This order, formerly Edentata, includes armadillos, anteaters and sloths.  All are found exclusively in the New World, although fossils are known from the Eocene of Europe and possibly Asia.  In fact, some researchers believe Xenarthrans may have been distributed worldwide in the Cretaceous but evidently became restricted to South America and remained there for most of their history, evolving into numerous groups.  The former order name (meaning "lacking teeth") is a misnomer, since only the anteaters lack teeth.  In fact, the giant armadillo may have as many as 100 teeth.  The name Xenarthra means "strange joint", referring to the extra articulations (called xenarthrales) found between the vertebrae connections.  These are insect eaters with degenerate teeth, consuming their prey whole without chewing using long mucus-covered tongues.  

It is believed that the sloths, anteaters, and armadillos diverged at least 75-80 million years ago and that they are at least as distinct from one another as are carnivores, bats, and primates.  Work by Sarich (1985) suggests that the Xenarthra separated from other placental mammals prior to the evolution of the latter into modern orders.  Earliest species are known to exist in the Paleocene, 55 million years ago.  With the opening of the Panama land bridge some 3 million years ago, certain species, including the giant sloths, glyptodonts and armadillos made their way into North America.  

The Xenarthra once were far more diverse than today; there are known to be ten times as many fossil as living genera. 

This order includes four families, 13 genera and 29 species (Nowak).  Of the 29 species of the dasypodidae family occurring in Central and South America, only the nine-banded armadillo exists in eastern US.

No members of the Xenarthra order are found in the Appalachian region, but the nearest member is included for its interest below.  Besides, it's my website, and I can include this ifin I wanna.


Family Dasypodidae – Armadillos

The name armadillo is Spanish for “little armored one”.  This family includes eight genera and twenty species, primarily located in the tropical regions of the New World.  Only the nine-banded armadillo is found in the United States. 

NINE-BANDED ARMADILLO (Dasypus novemcinctus) (?; nine, that which girds)


Appalachian Region Distribution: Not found north of southern South Carolina.
Continental Range: Originating in South America and Central America, armadillos spread north into Texas and Louisiana and then east to join the Florida-introduced populations (see Remarks below).  Populations seem to be migrating northwards.  Six subspecies known; one in SE US (D. novemcinctus mexicanus).
Abundance: Common.
Population Density: Wide range; from 0.2 to 1.2 per acre.
Both forested and semi-open habitats having sandy soils.
Size and Molt: 15" - 18"; 8 - 17 pounds (Males weighing several pounds more than females).
Mammae: Two pair.
Active Period: With little protective hair, they tend to be crepuscular to nocturnal in summer, and often a bit diurnal in the winter.  In temperature extremes, they will remain in their dens.
Diet: Omnivorous.  An accomplished digger, feeding on insects, reptiles, bird eggs and other small invertebrates (maybe 10% plant material).  Tends to forage by "rooting" like a pig.  Their taste for worms has caused problems among homeowners and golf course superintendents.
Home Range: A few acres to 35 acres, with 15 acres being the average.  Home ranges overlap
Social Structure: Solitary and active year-round.  Occasionally, several individuals may frequent a common burrow, though usually these animals are all of the same sex.  In high densities, considerable aggression is noted.
Life Cycle: One litter of four quadruplets per year (always of the same sex, from the same ovum), usually around April. Armadillos exhibit delayed implantation (fertilization of the egg occurs in July or August at mating, but implantation of the embryos in the uterus is delayed for normally about four months, although in one study, some females became pregnant two years after last contact with males). Ultimately, after a actual gestation period of 120 days, four identical embryos will result from one egg. Young are precocious and can walk and follow their mother on the first day.  Weaned after 4 to 5 months, with first breeding occurring at one year.  Life span in captivity is up to ten years, although two years is the norm in the wild.
Den/Nest: A burrowing animal, armadillos dig tunnels to numerous dens (1 ˝ to 10 feet below the surface) throughout its range using its nose and fore feet . Burrows are 7 - 8" in diameter and 2 - 24 feet in length, often along creek banks.   Den has a nest of leaves or grasses. Occasionally makes large surface nests, resembling miniature haystacks in clumps of saw palmetto.  Dens of several adults may be clumped together, and one adult may have several dens, including short straight burrows for escape.
Tracks: In sand, footprints are blurred and referred to as "hoof-like".  NAS calls them bird-like in appearance.  Foreprint 1 3/4" long, 1 5/8" wide.  Hindprint  more than 2" long and 1 5/8" wide.  Four front toes and five rear.  Armor shell drag is normally seen.
Scat: Round, pellet-like clay droppings (because they consume a lot of soil when they eat), about 1 3/8 inch wide.

Remarks:  First reported by John James Audubon and John Bachman in southern Texas, it has been expanding its range east and northward since then. It was first recorded in the Rio Grande Valley of southern Texas in the mid-1800’s.  In 1943, it moved east of the Mississippi River.  Although introduced to Florida in the 1920's, its "natural" migration reached Alabama in 1952 and by this time, had populated all of Florida.  They are the subject of biomedical and genetic research, due to the identical quadruplets and their susceptibility to leprosy (the only mammal other than man to be susceptible). Having degenerate teeth, this is the only North American mammal that is "armored". While some species of armadillos can curl into an armored ball, the nine-banded armadillo relies on running to safety. They have the ability to swim across bodies of water doggie-style, but often will literally walk along the bottom of the watercourse to the other side. Northern limit is defined by cold, with numerous animals in northern extremes showing signs of frost-bite. They are second only to opossum to number of road kills, owing partially to their reflexive nature of jumping straight up when frightened.

This nine-banded armadillo actually usually has eight bands in the northern parts of its range (SE US).