Animal Diversity Web

Ge­o­graphic Range

The dis­tri­b­u­tion of seven-banded ar­madil­los Dasy­pus septem­cinc­tus is lim­ited to the South Amer­i­can Con­ti­nent. Their ge­o­graph­i­cal range in the neotrop­i­cal re­gion ex­tends from the lower Ama­zon­ian Basin of Brazil to the Gran Chaco of Bo­livia, Paraguay and north­ern provinces of Ar­gentina: Salta, For­mosa, and Chaco. (Red­ford and Eisen­berg, 1989; Wil­son and Reeder, 2005)

• Biogeographic Regions
• neotropical
  • native

Habi­tat

Seven-banded armidil­los in­habit grass­lands, with the ex­cep­tion of south­east­ern Brazil, where they can be found in the gallery forests. (Red­ford and Eisen­berg, 1989)

• Habitat Regions
• terrestrial

• Terrestrial Biomes
• savanna or grassland

• Other Habitat Features
• riparian

Phys­i­cal De­scrip­tion

The most dis­tinct phys­i­cal char­ac­ter­is­tic of ar­madil­los, Dasy­po­di­dae, is the cara­pace that re­sem­bles gray or brown armor. The cara­pace is made of os­si­fied der­mal plates that re­sem­ble a thick hard­ened skin. The ma­jor­ity of an ar­madillo's body is cov­ered with the cara­pace, with the ex­cep­tion of the ab­domen re­gion. Seven-banded ar­madil­los have thick-skinned ab­domens with hair yel­low and/or white in ap­pear­ance. The cara­pace it­self is di­vided into three sec­tions: a scapu­lar shield, a pelvic shield, and a se­ries of bands around the mid­sec­tion. Seven-banded ar­madil­los have 6 to 8 bands lo­cated in the mid­sec­tion of the cara­pace. Nine-banded ar­madil­los, Dasy­pus novem­cinc­tus, a close rel­a­tive to the seven-banded ar­madillo, have 7 to 11 bands. (Fox, 1999; Ham­lett, 1939; Red­ford and Eisen­berg, 1989; Walker, 1975)

Nine-banded ar­madil­los, are sim­i­lar in ap­pear­ance to seven-banded ar­madil­los, though nine-banded ar­madil­los are larger in body size and typ­i­cally have two more bands in the mid­sec­tion of the cara­pace. Seven-banded ar­madil­los are the small­est of g. Dasy­pus with an av­er­age mass of 1.63 kg. Head and body length av­er­ages 269 mm while the tail mea­sures an ad­di­tional 147 mm. Seven-banded ar­madil­los have 4 dig­its on their forefeet and 5 dig­its on their hind feet. The ears are about half the size of their head, and they have a long flat­tened snout used to for­age for in­sects. (Fox, 1999; Ham­lett, 1939; Red­ford and Eisen­berg, 1989; Walker, 1975)

• Other Physical Features
• endothermic
• bilateral symmetry

• Sexual Dimorphism
• sexes alike

• Average mass

  1.47 kg

  3.24 lb

• Average length

  416 mm

  16.38 in

Re­pro­duc­tion

Lit­tle in­for­ma­tion is avail­able re­gard­ing mat­ing sys­tems of seven-banded ar­madil­los. How­ever, their close rel­a­tives, nine-banded ar­madil­los, ex­hibit a polyg­y­nous mat­ing sys­tem where the male mates with more than one fe­male. The male en­tices the fe­male for courtship by mark­ing an area with urine. The fe­male then re­sponds by lying on her back to ini­ti­ate cop­u­la­tion. The male and fe­male may briefly share a den after cop­u­la­tion. (Davis and Schimidly, 1997; Loughry, et al., 1998a; Voelker, 1986)

• Mating System
• polygynous

Lit­tle in­for­ma­tion for the breed­ing sea­son of seven-banded ar­madil­los is avail­able, though it is likely sim­i­lar to that of close rel­a­tives nine-banded ar­madil­los. Nine-banded ar­madil­los begin breed­ing in July and in rare oc­cur­rences ex­tend the breed­ing sea­son until De­cem­ber. Fe­male seven-banded ar­madil­los reach sex­ual ma­tu­rity around 274 days of age. The ges­ta­tion pe­riod for seven-banded ar­madil­los is re­ported to be 132 days and varies lit­tle to the ges­ta­tion pe­riod of 135 days for nine-banded ar­madil­los. While ges­ta­tion pe­ri­ods for seven-banded and nine-banded ar­madil­los may last a lit­tle over 130 days, the preg­nancy may last for an ad­di­tional 120 days due to fe­males' abil­ity to delay im­plan­ta­tion. De­layed im­plan­ta­tion oc­curs in all mem­bers of g. Dasy­pus and re­sults from the blas­to­cyst re­main­ing un­at­tached in the uterus while al­low­ing oxy­gen and nu­tri­tion to be re­leased from uter­ine se­cre­tions. De­layed im­plan­ta­tion usu­ally oc­curs for three months after fer­til­iza­tion and may re­sult from en­vi­ron­men­tal stress. Davis and Schmimidly (1997) state that de­layed im­plan­ta­tion may help the young of g. Dasy­pus avoid stress­ful con­di­tions and in­crease their chances of sur­vival. When im­plan­ta­tion oc­curs in seven-banded ar­madil­los, the blas­to­cyst di­vides to form 6 to 8 dis­tinct em­bry­onic growth cen­ters, which at­tach to the uterus by a shared pla­centa. This process is called poly­em­bry­ony and re­sults in a lit­ter of 6 to 8 iden­ti­cal off­spring. Seven-banded ar­madil­los fre­quently have lit­ter sizes of 6-8 young, even though all mem­bers of g. Dasy­pus have four teats. Lit­ter sizes are smaller for nine-banded ar­madil­los as they con­sis­tently have a lit­ter of four iden­ti­cal quadru­plets to com­ple­ment the num­ber of teats. After im­plan­ta­tion oc­curs for nine-banded ar­madil­los, a lit­ter is born fully formed with eyes open­ing in ap­prox­i­mately 4 months. The young can begin to walk within hours of birth and for­age with their mother within a few weeks. They are re­ported to wean within 2 months but may re­main with their mother for a few more months. The young are then ca­pa­ble of breed­ing in the early sum­mer of the fol­low­ing year. ("AnAge Entry for Dasy­pus septem­cinc­tus", 2009; Davis and Schimidly, 1997; Red­ford and Eisen­berg, 1989; Smith and Doughty, 1984; Walker, 1975)

• Key Reproductive Features
• seasonal breeding
• gonochoric/gonochoristic/dioecious (sexes separate)
• sexual
• delayed implantation

• Breeding interval

  Breeding patterns of seven-banded armadillos are likely similar to that of nine banded armadillos, which breed yearly.

• Breeding season

  Breeding patterns of seven-banded armadillos are likely similar to that of nine banded armadillos, which breed during early summer.

• Range number of offspring

  4 to 12

• Average number of offspring

  4 to 6

• Average gestation period

  132 days

• Average age at sexual or reproductive maturity (female)

  274 days

Lit­tle in­for­ma­tion is avail­able re­gard­ing parental in­vest­ment of seven-banded ar­madil­los.

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

Lifes­pan/Longevity

The max­i­mum lifes­pan re­ported for one spec­i­men of seven-banded ar­madil­los in cap­tiv­ity was ob­served to be 16.8 years. Other in­for­ma­tion is lim­ited in avail­abil­ity. ("AnAge Entry for Dasy­pus septem­cinc­tus", 2009)

• Range lifespan
  Status: captivity

  16.8 (high) years

Be­hav­ior

Seven-banded ar­madil­los are an aso­cial di­ur­nal species that com­monly take ad­van­tage of bur­rows made from other species and ex­pand these bur­rows by dig­ging hor­i­zon­tally any­where from four to twelve feet. They usu­ally have mul­ti­ple bur­rows and join these to a cen­tral den. When seven-banded ar­madil­los are not in their bur­rows, they are for­ag­ing in grass­lands and gallery forests with their snout close to the ground. While for­ag­ing, they use their sense of smell to prey on in­sects and other small an­i­mals. When pur­sued they re­treat to a bur­row and wedge them­selves against it mak­ing it dif­fi­cult for preda­tors to re­move them from their bur­row. (Carter and En­carnaçao, 1983; Ham­lett, 1939; Red­ford and Eisen­berg, 1989; Walker, 1975)

• Key Behaviors
• fossorial
• diurnal
• motile
• solitary

Home Range

There is lit­tle avail­able in­for­ma­tion on home range for seven-banded ar­madil­los.

Com­mu­ni­ca­tion and Per­cep­tion

Lit­tle in­for­ma­tion is avail­able re­gard­ing com­mu­ni­ca­tion and per­cep­tion of seven-banded ar­madil­los, but their close rel­a­tive nine-banded ar­madil­los have poor eye­sight and there­fore rely on their keen sense of smell. This sense of smell al­lows them to ef­fi­ciently for­age under leaf and grass lit­ter. Ol­fac­tory senses are also used for mate se­lec­tion and sib­ling recog­ni­tion. (Fox, 1999; Loughry, et al., 1998b; Smith and Doughty, 1984)

• Other Communication Modes
• scent marks

• Perception Channels
• visual
• tactile
• chemical

Food Habits

Seven-banded ar­madil­los are gen­er­ally con­sid­ered in­sec­ti­vores, al­though they could also be con­sid­ered slightly om­niv­o­rous as they oc­ca­sion­ally eat plants and other types of an­i­mal foods. Their diet mainly con­sists of in­sects such as ants, bee­tles, wasps, cater­pil­lars, roaches, ter­mites, and lar­vae. They may also eat other or­gan­isms such as small rep­tiles, am­phib­ians, and even bird car­casses. (Red­ford and Eisen­berg, 1989; Smith and Doughty, 1984; Walker, 1975)

• Primary Diet
• carnivore
  • insectivore
• omnivore

• Animal Foods
• birds
• mammals
• amphibians
• reptiles
• carrion
• insects
• terrestrial non-insect arthropods

Pre­da­tion

Lit­tle in­for­ma­tion is avail­able re­gard­ing pre­da­tion of seven-banded ar­madil­los. When pur­sued, seven-banded ar­madil­los usu­ally run and wedge them­selves in a bur­row en­sur­ing their ab­domen re­gion is pro­tected from pre­da­tion. Seven-banded ar­madil­los are not hunted by hu­mans as heav­ily as nine-banded ar­madil­los be­cause of their small size. (Ana­cleto, et al., 2006; Smith and Doughty, 1984; Walker, 1975)

• Known Predators

  • Humans

Ecosys­tem Roles

Seven-banded ar­madil­los are scav­engers, con­sum­ing a wide va­ri­ety of in­ver­te­brates as well as car­rion and oc­ca­sion­ally plants. Pri­mar­ily in­sec­tiv­o­rous, seven-banded ar­madil­los con­trol in­sect pop­u­la­tions. (Walker, 1975)

Eco­nomic Im­por­tance for Hu­mans: Pos­i­tive

Seven-banded ar­madil­los con­sume vast amounts of ter­mites and other in­sects con­sid­ered as pests to hu­mans. They are also used as sub­jects for lep­rosy med­ical re­search. (Red­ford and Eisen­berg, 1989; Walker, 1975; Red­ford and Eisen­berg, 1989; Walker, 1975; Red­ford and Eisen­berg, 1989; Smith and Doughty, 1984; Walker, 1975)

• Positive Impacts
• source of medicine or drug
• controls pest population

Eco­nomic Im­por­tance for Hu­mans: Neg­a­tive

Seven-banded ar­madil­los may bur­row un­der­neath man­made struc­tures caus­ing sup­port­ing soils to be­come in­sta­ble. (Red­ford and Eisen­berg, 1989; Smith and Doughty, 1984; Walker, 1975)

• Negative Impacts
• household pest

Con­ser­va­tion Sta­tus

Seven-banded ar­madil­los are listed on the IUCN Red List as least con­cern

• IUCN Red List

  Least Concern
  More information

• IUCN Red List

  Least Concern
  More information

• US Federal List

  No special status

• CITES

  Appendix I

Con­trib­u­tors

Je­remy Fruk (au­thor), North­ern Michi­gan Uni­ver­sity, John Brug­gink (ed­i­tor), North­ern Michi­gan Uni­ver­sity, Gail Mc­Cormick (ed­i­tor), An­i­mal Di­ver­sity Web Staff.

Ref­er­ences

2009. "AnAge Entry for Dasy­pus septem­cinc­tus" (On-line). An Age:The An­i­mal Age­ing and Longevity Data­base. Ac­cessed March 13, 2009 at http://​genomics.​senescence.​info/​species/​entry.​php?​species=Dasypus_​septemcinctus.

Ana­cleto, T., J. Di­niz-Filho, M. Vital. 2006. Es­ti­mat­ing po­ten­tial ge­o­graphic ranges of ar­madil­los (Xe­narthra, Dasy­po­di­dae) in Brazil under niche-based mod­els. Mam­malia, 70: 202-213.

Carter, T., C. En­carnaçao. 1983. Char­ac­ter­is­tics and use of bur­rows by four species of ar­madil­los in Brazil. Jour­nal of Mam­mal­ogy, 64: 103-108.

Davis, W., D. Schimidly. 1997. "Nine-banded Ar­madillo" (On-line). The Mam­mals of Texas - On­line Edi­tion. Ac­cessed March 12, 2009 at http://​www.​nsrl.​ttu.​edu/​TMOT1/​dasynove.​htm.

Fox, D. 1999. "Dasy­pus novem­cinc­tus" (On-line). An­i­mal Di­ver­sity Web. Ac­cessed March 16, 2009 at http://​animaldiversity.​ummz.​umich.​edu/​site/​accounts/​information/​Dasypus_​novemcinctus.​html.​.

Ham­lett, G. 1939. Iden­tity of Dasy­pus septem­cinc­tus Lin­naeus with notes on some re­lated species. Jour­nal of Mam­mol­ogy, 20: 328-336.

Loughry, W., P. Prodohl, C. Mc­do­nough, W. Nel­son, J. Avise. 1998. Cor­re­lates of re­pro­duc­tive suc­cess in a pop­u­la­tion of nine-banded ar­madil­los. Cana­dian Jour­nal of Zo­ol­ogy, 76: 1815-1821.

Loughry, W., G. Dwyer, C. Mc­do­nough. 1998. Be­hav­ioral in­ter­ac­tions be­tween ju­ve­nile nine-banded ar­madil­los (Dasy­pus novem­cinc­tus) in staged en­coun­ters. Amer­i­can Mid­land Nat­u­ral­ist, 139: 125-132.

Red­ford, K., J. Eisen­berg. 1989. Mam­mals of the Neotrop­ics, Vol­ume 2, The South­ern Cone: Chile, Ar­gentina, Uruguay, Paraguay. Chicago: Uni­ver­sity Chicago Press.

Smith, L., R. Doughty. 1984. The Amaz­ing Ar­madillo: Ge­og­ra­phy of a Folk Crit­ter. Austin Texas: Uni­ver­sity of Texas Press.

Voelker, W. 1986. The Nat­ural His­tory of Liv­ing Mam­mals. Med­ford, NJ: Plexus Pub­lish­ing, Inc.

Walker, E. 1975. Dasy­pus septem­cinc­tus. Pp. 501-503 in J Par­adiso, ed. Mam­mals of the World, Vol. 1, 3 Edi­tion. Bal­ti­more and Lon­don: John Hop­kins Uni­ver­sity Press.

Wil­son, E., D. Reeder. 2005. "Mam­mal species of the world. A Tax­o­nomic and Ge­o­graphic Ref­er­ence 3rd ed." (On-line). Wil­son & Reeder's Mam­mal Species of the World. Ac­cessed March 11, 2009 at http://​www.​bucknell.​edu/​MSW3.