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About Giant Armadillos

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Priodontes maximus

Weight: Up to 50 kilograms (110 pounds)
Length: Up to 1.5 meters (5 feet)

This is the largest of the armadillo species. Although giant armadillos range over much of South America, very little is known about them and most information is anecdotal.  Due to its cryptic behavior and low population densities, this animal is very rarely seen.  The giant armadillo is threatened with extinction and is currently classified as Vulnerable (A2cd) by the IUCN/SSC Red List of Threatened Species.

Strong Claws for Digging

One of the most striking features of the species is the large scimitar-shaped foreclaws, the third of which is greatly enlarged and can reach over 20 cm (7.9 in).

The project confirmed that giant armadillos are nocturnal, spending the daytime period deep in their burrows. They are extremely powerful diggers and their very large excavations are easily recognized. On average, openings are 35 cm (13.8 in) in diameter. These holes are often the only evidence of the species presence in an area.


Ecosystem Engineers

On average, a giant armadillo spends three nights in a burrow before digging a new one. By doing so, they alter their physical surroundings and constantly create new habitats.


Our team has analyzed over 55,000 images confirming at least 57 vertebrate species use these burrows as a thermal refuge, shelter against predators, and as a feeding ground.


Many of these also rest in the soft sand mound in front of the burrow. This rarely seen creature may play a crucial role in the lives of many of the most popular species in the South American landscape. 

Armored Giants

Giant armadillos have a large, dark dorsal armor with many narrow bands. The armor is marked laterally on its edge by a distinctive lighter band that surrounds the entire carapace.

Legs, tail and head are also covered with tough pentagonal scales. Underneath the carapace, the bare skin is pinkish, wrinkly, and unprotected.


Rare in Their Range

Although widespread, giant armadillos are rare over their entire distribution range including the Pantanal. Giant armadillos range over much of South America in 12 different countries (Argentina, Bolivia, Brazil, Colombia, Ecuador, French Guiana, Guyana, Paraguay, Peru, Suriname, Uruguay, and Venezuela) and are found in a diversity of habitats ranging from tropical forests to open savannas.  

 In Brazil, except in the Northeast, the species is found throughout most of the country, although it is probably extinct or near extinct in the South.

In addition to the Pantanal, the species has been registered throughout the Amazon, Atlantic Forest, and Cerrado biomes in Brazil.

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Fast Digging for Food

One night, our team observed a giant armadillo digging 6 holes an average of 80 cm deep in less than fifteen minutes to feed on ants. Collection of fecal samples confirms their myrmecophagous (ant-eating) nature. They can break through termite mounds in a matter of minutes. In the Pantanal, over 90% of the termite mounds regenerate themselves in a matter of weeks.



No reliable information is available on their reproduction. However, the Giant Armadillo Project recorded the first evidence of mating and birth. Our observations showed that the gestation period last 5 months and only one young is born. 


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Already naturally rare throughout their distribution, it appears giant armadillos are becoming even rarer because of anthropogenic impacts.

Due to the large size of adult giant armadillos, these animals can become a preferred hunting target of local communities and subsistence hunters in the Amazon. Although difficult to quantify, it may also be targeted by collectors for its giant middle foreclaw.

Other impacts contributing to the decline of populations include fire and roadkill. Currently, virtually nothing is known about the effect of infectious diseases on giant armadillos.

Many collaborative efforts are required if giant armadillos and all the species they depend on are to survive.