Chaetophractus villosuslarge hairy armadillo

Ge­o­graphic Range

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

Habi­tat

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
    AnAge
  • Range length
    220 to 400 mm
    8.66 to 15.75 in
  • Average basal metabolic rate
    4.508 W
    AnAge

Re­pro­duc­tion

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
    2
  • Average number of offspring
    2
    AnAge
  • Average gestation period
    2 months
  • Average gestation period
    67 days
    AnAge
  • 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
    AnAge
  • Average age at sexual or reproductive maturity (male)
    9 months
  • Average age at sexual or reproductive maturity (male)
    Sex: male
    273 days
    AnAge

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

Lifes­pan/Longevity

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

Be­hav­ior

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

Pre­da­tion

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

Con­trib­u­tors

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

Glossary

Neotropical

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

World Map

altricial

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.

carrion

flesh of dead animals.

chemical

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.

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

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.

fertilization

union of egg and spermatozoan

food

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

iteroparous

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).

motile

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.

nocturnal

active during the night

omnivore

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

scrub forest

scrub forests develop in areas that experience dry seasons.

sexual

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

tactile

uses touch to communicate

terrestrial

Living on the ground.

tropical

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

viviparous

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

Ref­er­ences

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 http://​www.​msu.​edu/​~nixon­jos/ar­madillo/index.​html?http://​www.​msu.​edu/​~nixon­jos/ar­madillo/chaetophractus.​html.

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