Chaetophractus vellerosus - Screaming hairy armadillo
Chaetophractus vellerosus is
in the order Xenarthra (Edentata), family
Dasypodidae, and subfamily Dasypodinae. The genus also includes C. nationi and
C. villosus (ADW).
It is distinguished from other Chaetophractus species by possessing much longer ears
(Redford and Eisenberg, 1992) and is also the smallest and most slender of the
hairy armadillos (Neris et al., 2002) weighing
usually less than 1 kg (Greegor, 1979b). C. vellerosus
possesses characteristic armor that includes a shielded head and back of neck
and a 6 to 8 banded carapace (ADW).
This species has more hair than most armadillos (Redford and Eisenberg, 1992).
The bristles on the dorsum are usually tan and project from between the scales
of the body armor. The male is generally larger than the female (ADW) with both
sexes being heavier in the winter due to a 1 to 2 cm layer of subcutaneous fat
(Redford and Eisenberg, 1992).
vellerosus is common in the northern Monte Desert
of Argentina (Greegor, 1979a), the Gran Chaco of Bolivia,
(Redford and Eisenberg, 1992) and central Chile
(Neris et al., 2002). It inhabits the terrestrial biomes of desert, dune, savanna, grassland and scrub forest (ADW).
breeds in the autumn followed by a
gestation period of 60 to 75 days with more than one litter annually. Litters
usually consist of 2 young— often one female and one male weighing around 155 g
at birth. They open their eyes after16 to 30 days, are weaned at 50 to 60 days,
and reach sexual maturity at 9 months. They are gonochoric
, and dioecious
Ecology and Behavior:
handled, C. vellerosus
frequently emits loud cries of protest (Redford and Eisenberg, 1992). This
solitary species is generally active at night in the summer to avoid
overheating and becomes diurnal in the winter (Neris
et al., 2002). They are also fossorial
desiccation—often burrowing up to several meters (ADW).C. vellerosus
inhabits open areas and appears to be better
adapted to semiarid conditions (Neris
et al. 2002).
Of these xeric areas, they are found in low
high altitudes, but are not found in rocky soils where burrow construction is
impeded. Rainfall in their range is
between 200 and 600 mm, but a population exists in eastern Buenos
Aires province, Argentina
where the annual rainfall is 1000 mm. They create sloping burrows with diameters
ranging from 8 to 15 cm, several meters long, may have multiple entrances, and
are often at the base of shrubs. No nest is apparently built in the burrow, and
the entrance is usually sealed when the animal is inside (Redford and
The minimum home range
among 7 C. vellerosus
tracked with trailing devices was 3.4 ha (Greegor
spends the majority of its time outside the burrow foraging. Their diet varies
seasonally. During the summer, their major food item is insects, mostly from
the beetle family (ADW). In the winter, their diet is mainly plant material,
especially pods from the Prosopis
tree. A significant part of their diet is vertebrates (28% in the summer and
14% in the winter) including anurans, lizards, birds and mice (Redford and
Eisenberg, 1992; Greegor
, 1979a). C. vellerosus
also ingests a large amount of sand while foraging. Sand can compose 50% of the
volume of a single stomach (Greegor
, 1979a; Redford
and Eisenberg, 1992). They also feed on garbage and animal carcasses (Neris
et al., 2002). This species has the capacity to go
for long periods without drinking water because they have a very efficient
, 1979a) that can generate highly
concentrated urine (ADW) and the capacity to use moisture from plant material
, 1979a). C. vellerosus
is common in the distribution area (Neris
et al., 2002).
Indigenous people consume their
meat, but farmers do not because of their necrophagaic
habits (Neris et al., 2002).
Greegor Jr., D. H. 1979(a). Diet of the little hairy armadillo, Chaetophractus vellerosus, of
northwestern Argentina. Journal of Mammalogy.
Greegor Jr., D. H. 1979(b). Preliminary study of movements and home range of the armadillo, Chaetophractus vellerosus.
Journal of Mammalogy. 61(2):334-335.
Neris, N., F. Colmán, E. Ovelar,
N. Sukigara and N. Ishii. 2002. Kato’s Data
Book on Larger Mammals of Paraguay:
Distribution, Population Trends and Utilization. Secretaria del Ambiente.
Porrett, M. 1999. "Chaetophractus
vellerosus" (On-line), Animal Diversity Web. Accessed
2004 at http://animaldiversity.ummz.umich.edu/site/accounts/information/Chaetophractus _vellerosus.html.
Redford, K.H. and
J.F. Eisenberg. 1992. Mammals of the Neotropics:
The Southern Cone, Volume 2 (Chile,
University of Chicago Press.
Reference written by
Margaret Edwards, Biol 378 (Mammalogy),
University of Wisconsin – Stevens
Point: Edited by Christopher Luddington. Page last
updated March 4, 2005.