Katie Perryman Average head and body length 220-400mm Average tail length 90-175mm

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Katie Perryman
Description:
Average head and body length 220-400mm
Average tail length 90-175mm
Average weight 2.02kg
The large hairy armadillo (Chateophractus villosus) is the largest armadillo
in the genus Chateophractus (Redford and Eisenberg 1992). Like other
armadillos it is covered in armor. The armor develops from skin and is made up
of hard bony plates called scutes (MacDonald 2001). The carapace (armor)
protects the shoulders, back, sides, and rump (Nowak 1999). The central portion
of the armor is made up of about 18 bands, 7-8 of which are movable. In
addition to the carapace, there is a shield on the head and between the ears.
Some individuals in this species have 3-4 holes in the pelvic region of the armor
that open to glandular pits (Redford and Eisenberg 1992). The large hairy
armadillo, as the name suggests, has more hair than other armadillos. Hair
projects from the scales of the armor, and whitish to light brown hairs cover the
belly (Nowak 1999). C. villosus has 5 claws on the hind limbs and 3, 4, or 5
claws on the very powerful forelimbs. These animals have 14-18 teeth in each
jaw (MacDonald 2001). C. villosus being a member of the dasypodidae family
has simple oval teeth in cross section (Vizcaino et al 2004). They have poor
eyesight, and well developed hearing (MacDonald 2001).
Distribution:
C. villosus is found in South America, from northern Paraguay, to the Gran
Chaco of Bolivia to central Argentina (Redford and Eisenberg 1992). The large
hairy armadillo is found in two national parks in Paraguay, the Defensores del
Chaco in northern Paraguay and the Teniente Enciso in northwest Paraguay
(Yahnke 1998).
Ontogeny and Reproduction:
Males and females of the species mate in September, but males have
been observed mounting females in every month of the year (Redford and
Eisenberg 1992). The males follow the females until they are ready to breed. Up
to 1/3 of females will fail to breed each year. Lactating and pregnant females can
be very aggressive (MacDonald 2001). Females build a nest by collecting leaves
under their body and then kicking it behind them to form a mound. The females
will growl at anything disturbing their nest site (Redford and Eisenberg 1992).
They experience a 60-75 day gestation period. There is more than 1 litter
annually. Usually fraternal twins are born, one male and one female (MacDonald
2001). Birth occurs from February to December (Redford and Eisenberg 1992).
The young weigh 155 g at birth and open their eyes after 16-30 days. They are
weaned at 50-60 days, and reach sexual maturity at 9 months (Nowak 1999).
The young are active in the late morning or the early afternoon (MacDonald
2001).
Ecology and Behavior:
C. villosus is an omnivorous species (Machiote 2004). They eat mainly
invertebrates. They move slowly along the ground with their nose in the soil or
leaf litter. They dig up material and open rotten logs with their fore claws. These
animals will burrow under and into carcasses to reach maggots (MacDonald
1999). They also consume plant matter, carrion, eggs, occasional snakes and
lizards (MacDonald 2001). Some have been seen killing snakes by jumping on
them and cutting them with the edge of their armor (Nixon 2004). C. villosus
preys on Kelp gulls (Larus domnicanus) in Patagonia, Argentina (Borboroglu and
Yorio 2003). The large hairy armadillo also preys on Imperial Cormorants
(Phalacrocorax atriceps) and Rock Shags (Phalacrocorax magellanicus) in
Patagonia, Argentina (Punta et al 2002).
C. villosus is solitary except when rearing young or mating (Machiote
2004). These animals inhabit open areas in semi-desert conditions (Nowak
1999). C. villosus also inhabits desert, temperate grassland, and forest. They
have an average home range or 3.4 hectares (Nixon 2004). They can tolerate
very dry conditions (MacDonald 2001). These mammals have a low body
temperature (24-35.2ºc) to conserve heat and moisture. They can also shiver to
generate heat. They spend the coldest and hottest parts of the day underground.
C. villosus shifts activity to forage in the warm mid-day or the cool and moist
evening, but they are mostly nocturnal. The large hairy armadillo may have
extensive burrow systems (MacDonald 2001). They occupy burrows for only
short periods of time, and then move to a new one (Machicote 2004).
The hairy armadillo is predated upon by canines, aves, and humans
(Nixon 2004). When chased the hairy armadillo first tries to run away and may
snarl. It tries to find a hole or will burrow into the ground to avoid predators. It
anchors itself in its burrow by spreading its feet out sideways and bending its
body so the hind edges of the bands cling to the burrow wall (Nowak 1999). If it
can not outrun its pursuer, it withdraws its limbs under the carapace and sits as
tightly to the ground as possible (MacDonald 1999).
Remarks:
The hairy armadillo can live 8-12 years in the wild. There are reports of
them living up to 30 years in captivity (MacDonald 2001).
Armadillos can become infected with leprosy. They exhibit no external
symptoms until the disease has progressed significantly. It was first found in
populations of armadillos in the 1970s.
C. villosus is hunted by humans for food and because they cause damage
to agricultural lands (Nixon 2004). The species has some unique features that
make it coveted for biomedical research (Codon 1999). Also, it is the second
most common armadillo found in zoos (Nixon 2004).
Literature Cited:
Borboroglu, Pablo Garcia and Pablo Yorio. 2003. Habitat requirements and selection by
Kelp Gulls (Larus domnicanus) in central and northern Patagonia, Argentina.
The Auk. Vol.121. No.1. Pages 243-252.
Codon, S.M., Estecondo, S.G., Galindez, E.J., and Casanave, E.B. 1999. Ultrastructure
and morphometry of ovarian follicles of the armadillo Chaetophractus villosus
(mammalia, dasypodidae). Departmento de Biologia. Universidad Nacional
del Sur, San Juan.
MacDonald. David. Encyclopedia of Animals. 1999. Barnes and Noble Books. New
York. Pages 796-798
MacDonald, Dr.David. Encyclopedia of Animals. 2001. Facts on File Inc. Andromeda
Oxford Limited. Pages 281-283.
Machicote, Marcela, Branch, Lyn C. & Villarreal, Diego. 2004. Burrowing owls and
burrowing mammals: Are ecosystem engineers interchangeable as facilitators?
Oikos.Vol 106. Issue3. Pages 527-535.
Nixon, J. “Hairy Armadillos: Three Species” http://www.msu.edu/~nixonjos/armadillo/
Index.html?. Accessed 30 September 2004.
Nowak, Ronald M. Walkers Mammals of the World. Sixth Edition. Vol 1. 1999. The
Johns Hopkins University Press. Baltimore.
Punta, Gabriel Pablo; Yorio Jose Saravia, and Pablo Garcia Borboroglu. Breeding
Habitat requirements of the Imperial Comorant and Rock Shag in Central
Patagonia, Argentina. 2002. Waterbirds. Vol.26. No.2. Pages 176-183.
Redford, Kent and John Eisenberg. Mammals of the Neo-Tropics: The southern cone:
Chile Argentina, Uruguay and Paraguay. 1992. Vol.2. University of Chicago
Press. Pages 54-56.
Vizcaino, Sergio and Gerardo De Luliis. 2003. Evidence for advanced carnivory in fossil
armadillos: Mammalia Xenartha Dasypodidae. Paleobiology. Vol.29.
No 1. Pages 123-128
Yahnke, Christopher Isabel Gamarra de Fox and Flavio Colman. Mammalian species
Richness in Paraguay: The effectiveness of national parks in preserving
Biodiversity.1998.Biological Conservation.Vol 84. No3. Pages 263-268
Reference written by Katie Perryman, Biology 378 student. Edited by Christopher Yahnke.
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