Chaetophractus villosuslarge hairy armadillo

Geographic Range

Chaetophractus villosus inhabits northern Paraguay and southern Bolivia to central Argentina (Nowak, 1999).


Chaetophractus villosus is best adapted to open, semidesert environments.

Physical Description

Armadillos have a double layer of horn and bone over the majority of their dorsal side. This protective layer consists of bands and plates which are surrounded by flexible skin (Nowak, 1999). A small shield on the head protects the ears and back of the neck. The carapace protects the shoulders, back and side of the body and consists of approximately 18 bands, 7 to 8 of which are movable (Nowak, 1999). The ventral area is covered by soft skin. Hair extends from between the scales and also covers this soft ventral skin. The skin is brown to pinkish in color and the hair is grayish brown to white (Nowak, 1999). The skulls of C. villosus are flattened dorsoventrally and have peglike teeth, which are evergrowing (Nowak, 1999).

  • Average mass
    2 kg
    4.41 lb
  • Average mass
    2000 g
    70.48 oz
  • Range length
    220 to 400 mm
    8.66 to 15.75 in
  • Average basal metabolic rate
    4.508 W


Mating takes place in September and gestation lasts for 60 to 75 days (Nowak, 1999). There is more than one litter per year. Litters are generally composed of two young (Nixon, 2001).

  • Breeding season
    September (mating) to December (birth)
  • Average number of offspring
  • Average number of offspring
  • Average gestation period
    2 months
  • Average gestation period
    67 days
  • Range weaning age
    50 to 60 days
  • Average age at sexual or reproductive maturity (female)
    9 months
  • Average age at sexual or reproductive maturity (female)
    Sex: female
    273 days
  • Average age at sexual or reproductive maturity (male)
    9 months
  • Average age at sexual or reproductive maturity (male)
    Sex: male
    273 days

At birth C. villosus weighs 155 g. Young open their eyes at 16-30 days (Nixon, 2001). Chaetophractus villosus is born with a soft, leathery skin which hardens with age (Nowak, 1999). The hairy armadillo is weaned 50 to 60 days after birth and is sexually mature at nine months of age (Nowak, 1999).

  • Parental Investment
  • altricial
  • pre-fertilization
    • provisioning
    • protecting
      • female
  • pre-hatching/birth
    • provisioning
      • female
  • pre-weaning/fledging
    • provisioning
      • female
    • protecting
      • female


The maximum lifespan of a captive hairy armadillo is 30 years (Nixon, 2001).


Chaetophractus villosus burrows to escape predation, to search for food, and to decrease body temperature on hot desert days (Casanave, 1995). They become more nocturnal during summer to avoid heat (Nixon, 2001).

Communication and Perception

Food Habits

Chaetophractus villosus is an omnivore that feeds on insects, invertebrates, small vertebrates, plants and carrion (Nowak, 1999). The hairy armadillo burrows under carcasses to obtain maggots and grubs. During the winter over half its food consumption consists of vegetation (Nowak, 1999). However, the majority of the year they feed on a variety of small vertebrates, rodents, lizards, etc. (Nixon, 2001).

  • Animal Foods
  • mammals
  • reptiles
  • carrion
  • insects
  • terrestrial non-insect arthropods
  • Plant Foods
  • fruit


The hairy armadillo is an efficient burrower, which helps it escape predators (Nowak, 1999). C. villosus is preyed upon most often by canines, aves, and humans (Nixon, 2001). When threatened, the armadillo draws its feet under its body and flattens its body to the ground, leaving only its armor exposed.

Economic Importance for Humans: Positive

Chaetophractus villosus is hunted for food by humans.

  • Positive Impacts
  • food

Economic Importance for Humans: Negative

Chaetophractus villosus burrow extensively and can cause damage to crops (Nowak, 1999).

  • Negative Impacts
  • crop pest

Conservation Status


Sarah Abbott (author), University of Michigan-Ann Arbor, Ondrej Podlaha (editor), University of Michigan-Ann Arbor.



living in the southern part of the New World. In other words, Central and South America.

World Map


young are born in a relatively underdeveloped state; they are unable to feed or care for themselves or locomote independently for a period of time after birth/hatching. In birds, naked and helpless after hatching.

bilateral symmetry

having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.


flesh of dead animals.


uses smells or other chemicals to communicate

desert or dunes

in deserts low (less than 30 cm per year) and unpredictable rainfall results in landscapes dominated by plants and animals adapted to aridity. Vegetation is typically sparse, though spectacular blooms may occur following rain. Deserts can be cold or warm and daily temperates typically fluctuate. In dune areas vegetation is also sparse and conditions are dry. This is because sand does not hold water well so little is available to plants. In dunes near seas and oceans this is compounded by the influence of salt in the air and soil. Salt limits the ability of plants to take up water through their roots.

  1. active during the day, 2. lasting for one day.

animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.


union of egg and spermatozoan


A substance that provides both nutrients and energy to a living thing.


offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).


having the capacity to move from one place to another.

native range

the area in which the animal is naturally found, the region in which it is endemic.


active during the night


an animal that mainly eats all kinds of things, including plants and animals

scrub forest

scrub forests develop in areas that experience dry seasons.


reproduction that includes combining the genetic contribution of two individuals, a male and a female


uses touch to communicate


Living on the ground.


the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.


reproduction in which fertilization and development take place within the female body and the developing embryo derives nourishment from the female.

year-round breeding

breeding takes place throughout the year


Casanave, E. 1995. Decrease in Body Temperature in Armadillos Experimentally covered by Soil. *Archives of Physiology and Biochemistry*, 103(1): 29-32.

Nixon, J. "Hairy Armadillos: Three Species" (On-line). Accessed November 20,2001 at

Nowak, R. 1999. *Walker's Mammals of the World*. Baltimore, MD: Johns Hopkins University Press.