Priodontes maximus

Geographic Range

Giant armadillos, Priodontes maximus , range through much of the neotropics. They are found from southeastern Venezuela and the Guianas in the north through northeastern Brazil, Paraguay, and the extreme north of Argentina. Most of this species' range lies within the Amazon basin.

• Biogeographic Regions
• neotropical neotropical
  • native native

Habitat

Priodontes maximus is typically found in a diverse range of habitats, usually in areas with a large termite population. Although rare, they have been sighted in tropical and subtropical rainforest, savanna, Brazilian floodplains, and arid and semiarid woodlands. In these areas, the armadillos have been found residing up to 500 meters above sea level.

• Habitat Regions
• tropical tropical
• terrestrial terrestrial

• Terrestrial Biomes
• savanna or grassland savanna or grassland
• forest forest
• rainforest rainforest
• scrub forest scrub forest

• Other Habitat Features
• agricultural agricultural

Physical Description

Priodontes maximus is easily distinguished from other armadillos due to its enormous size. In most cases, it weighs upwards of 26 kg, and measures between 832 and 960 mm. Another recognizable characteristic is its enlarged central claw, much like that of giant anteaters, Myrmecophaga tridactyla . Typical of armadillos, Priodontes maximus has a carapace covered with bony scales. The dorsal portion of this carapace appears black/gray, while the ventral portions of the carapace are much lighter and separated by a noticeable band. Underneath the carapace, the naked body appears wrinkly and pinkish. The legs and tail are covered with tough pentagonal scales. The head is conical, with a blunt rostrum.

• Other Physical Features
• endothermic endothermic
• homoiothermic
• bilateral symmetry bilateral symmetry

• Sexual Dimorphism
• sexes alike

Reproduction

Very little information is available on the mating habits of South American armadillos. No accounts of the mating system of P. maximus have been published as yet. Considering the habits of other armadillos, however, one may infer that two giant armadillos pair for each breeding season while sharing a burrow.

• Mating System
• monogamous monogamous

Very little is known about the reproductive behavior of giant armadillos. They typically give birth to a single offspring (occasionally two), which weigh up to 113 g at birth, and already possess tough skin. Weaning begins about 4 to 6 weeks after birth, and after weaning, the young become independent. Armadillos reach sexual maturity within 9 to 12 months of birth.

• Key Reproductive Features
• iteroparous iteroparous
• gonochoric/gonochoristic/dioecious (sexes separate)
• sexual sexual
• fertilization fertilization
• viviparous viviparous

Little is known about parental care in giant armadillos. Mothers stay with the young and nurse them for 4 to 6 weeks. Afterwards, the young stay with the mother until they reach independence at around 6 months of age. The role of the male in parental care has not been documented for P. maximus .

• Parental Investment
• no parental involvement
• female parental care female parental care
• pre-fertilization
  • protecting
    • female
• pre-hatching/birth
  • provisioning
    • female
  • protecting
    • female
• pre-weaning/fledging
  • provisioning
    • female
  • protecting
    • female

Lifespan/Longevity

The lifespan of these animals can reach 12 to 15 years.

Behavior

Priodontes maximus is largely nocturnal and terrestrial. These armadillos forage alone, only assosciating with others to mate. They dig large burrows in which they rest, using their spade-like third claws. These animals are capable of balancing on their hind legs and tail, allowign them to reach high into termite mounds (this technique also comes in handy for warding off predators). Once a mound has been eradicated, an armadillo will bury itself beneath the remains of the mound and reside there for a period up to 24 hours before moving on. It has been said that P. maximus is also a good swimmer.

• Key Behaviors
• terricolous
• fossorial fossorial
• nocturnal nocturnal
• motile motile
• nomadic nomadic
• solitary solitary

Home Range

The home range of P. maximus spans 450 hectares minimum, with a maximum of 3 square kilometers.

Communication and Perception

No information exists suggesting any sort of communication between animals. The strongest sense possessed by armadillos is olfaction, which could support a case for the presence of an olfactory communication channel between individuals. However, this is merely speculation and has yet to be tested.

Tactile communication undoubtedly occurs between a mother and her offspring, as well as between mates.

• Communication Channels
• tactile tactile
• chemical chemical

• Perception Channels
• visual visual
• tactile tactile
• acoustic acoustic
• chemical chemical

Food Habits

Giant armadillos have a very specialized diet consisting of termites and certain ant species. These animals roam throughout their range in search of termite mounds in which to burrow. Once they have found a mount, they completely eradicate it. This species has also been documented eating carrion, worms, and other small vertebrates.

• Primary Diet
• carnivore carnivore
  • insectivore insectivore

• Animal Foods
• reptiles
• carrion carrion
• insects
• terrestrial worms

Predation

Due to the large size and heavy shielding of these animals, giant armadillos have few natural predators. Unlike other armadillos, P. maximus cannot completely hide itself within its carapace. They occasionally fall prey to jaguars ( Panthera onca ), and pumas ( Puma concolor ). Humans, however, have had the deadliest impact on the species.

Ecosystem Roles

The most notable ecosystem role played by P. maximus is its control over the termite and ant populations in a small region. By keeping these huge populations in check, the ecosystem can maintain a state of equilibrium, making P. maximus somewhat of a keystone species. Also, due to its fossorial nature, this species aids in soil aeration.

• Ecosystem Impact
• soil aeration soil aeration
• keystone species keystone species

Economic Importance for Humans: Positive

At one point, before their numbers dwindled, giant armadillos were key in controlling leafcutter ant populations, which could reach enormous sizes and destroy crops. These animals have also been hunted by natives for their meat.

• Positive Impacts
• food food
• controls pest population

Economic Importance for Humans: Negative

Although giant armadillos can be damaging to crops while digging through soil in search of animal prey, they never directly consume plants.

• Negative Impacts
• crop pest

Conservation Status

Priodontes maximus is a victim of habitat infringement and overhunting. Many native farmers kill the armadillo on sight because they are thought to damage crops.

Additional Links

Encyclopedia of Life

Contributors

Nancy Shefferly (editor), Animal Diversity Web.

David Armitage (author), Animal Diversity Web, Phil Myers (editor, instructor), Museum of Zoology, University of Michigan-Ann Arbor.

References

Eisenberg, J., K. Redford. 1999. Mammals of the Neotropics: The Central Neotripics. Vol. 3: Ecuador, Peru, Bolivia, Brazil . Chicago & London: University of Chicago Press.

Emmons, L. 1997. Neotropical Rainforest Mammals . Chicago: University of Chicago Press.

Husson, A. 1978. The Mammals of Suriname . Leiden, The Netherlands: E.J. Brill.

Linares, O. 1998. Mamiferos de Venezuela . Caracas: Sociedad Conservacionista Audobon De Venezuela.

McBee, K., R. Baker. 1982. Dasypus novemcinctus . Mammalian Species , 162: 1-9. Accessed March 09, 2004 at http://www.science.smith.edu/departments/Biology/VHAYSSEN/msi/ .

Nowak, R. 1999. Walker’s Mammals of the World, Sixth Edition. . Baltimore and London: The Johns Hopkins University Press.

Parera, A. 2002. Los mamiferos de la Argentina y la region austral de Sudamerica . Buenos Aires: El Ateneo.