Found in the Chaco region of western and central Bolivia, Paraguay, and extreme northern Argentina, thegreater fairy armadillo (Calyptophractus retusus) has a head and body length of 140 — 175 mm (5.5 — 6.9 in) and a tail length35 mm (1.4 in).
C. retusus is larger than the lesser or pink fairy armadillo (Chlamyphorus truncatus). The shell plates are whitish or yellowish brown. Body hair is whitish and wooly. C. retusus resembles C. truncatus except the shell is securely attached to the body along its entire length, and the tail is rounded and partly covered with plates.
The greater fairy armadillo inhabits dry grasslands and sandy plains with thorn bushes and cactus. C. retususfeeds primarily on ants and ant larvae; they are also known to eat worms, snails, roots and other plant material.
C. retusus is not as rapid a burrower as C. truncatus; it probably presses its body close to the ground rather than burrowing if it is threatened. C. retusus has been reported to emit cries similar to those of human infants.
C. retusus is listed by the IUCN as vulnerable due to habitat loss and predation by domestic dogs. It does not do well in captivity.