Brown bristle armadillo

Brown bristle armadillo
Brown bristle armadillo
Systematics
Order : Armored siderails (Cingulata) without rank: Armadillos (Dasypoda) Family : Chlamyphoridae Subfamily : Euphractinae Genre : Bristle armadillos ( Chaetophractus ) Type : Brown bristle armadillo
Scientific name
Chaetophractus villosus
( Desmarest , 1804)

The brown-bristle armadillo or brown-haired armadillo ( Chaetophractus villosus ) is the largest representative of the bristle armadillos and lives mainly in the southern area of South America , east of the Andes . It prefers dry and open landscapes and feeds omnivorously , with the amount of plant and animal food depending on the seasons. In addition, the armadillo also prey on small vertebrates. The underground burrows created by the brown-bristle armadillo are sometimes quite complex. The population of the armadillo is not considered endangered.

features

Habitus

The brown bristle armadillo reaches a head-trunk length of 26 to 34 cm, the tail has a length between 11 and 16 cm. The weight varies from 1 to 3.9 kg and averages 2.4 kg; Animals in captivity can become much heavier as they tend to accumulate fat. In terms of weight, the armadillo is the larger of the two representatives of the bristle armadillo genus . The head of the animal has a short and wide shape and is characterized by the distinctive head shield. This is very large and triangular in shape, has a clearly curved profile on the side and protrudes almost to the tip of the nose. The head shield is made up of small bony plates, which, however, have a rather irregular shape. The ears stand wide apart, are funnel-shaped and around 2.4 cm long. Typically for armadillos, the body is covered by an armor that extends to the base of the legs. It consists of several rows of small bone platelets and looks very flat overall, the areas above the shoulder and pelvic girdles are more solid. In between there are 7 to 8 movable ligaments, which are also made up of small bone platelets. As additional protection, similar bands appear on the neck, as well as on the strong tail, up to 8 cm wide at the base. Two to three small openings for glands are embedded in the middle bone platelets of the pelvic shell . Individual long and thick hairs grow on the back armor, the fur is thicker on the sides of the body, on the legs, on the stomach and on the cheeks. The color of the hair ranges from black on the back and sides to lighter shades predominantly on the stomach. The skin and shell of the animal are dark brown in color with slightly lighter shades on the sides. The short limbs each end in five rays with claws. The claws are flattened on the sides and reach 1.5 to 2.5 cm in length on the front feet. The rear foot becomes about 4.9 cm long.

Skeletal features

Skull of the brown bristle armadillo ( Museum Wiesbaden collection )

The skull is 10 cm long and up to 11 cm wide on the cheekbones . The lower jaw is generally quite slim and reaches up to 7.3 cm in length and 0.51 to 1.14 cm in height (measured on the first and last tooth). It is noteworthy that females have an average larger lower jaw than males, one of the few diagnosable gender differences in the brown-bristle armadillo. The length of the rows of teeth on the lower jaw is 4.6 cm in females and 4.2 cm in males. The teeth do not correspond to those of most mammals . They are generally molar- shaped, with nine such teeth per jaw branch in the upper jaw and ten in the lower jaw, a total of 38. The height of the teeth is 0.5 cm. As with the other armadillos, the ulna shows marked adaptations to a burrowing way of life: the entire bone is 6.4 cm long, but the upper joint end ( olecranon ) alone takes up 2.6 cm. However, the proportional relationship between these two lengths is somewhat less than that of other armadillos, such as the bare-tailed armadillos .

Sensory performances and vocalizations

Like most armadillos , the brown-bristle armadillo has a poorly developed sense of sight . Female animals that are disturbed on the construction site give off a growl, and animals from captivity are also known to grunt. Suckling young animals are noticeable by a cat-like purr.

distribution and habitat

Distribution area

The habitat of the brown-bristle armadillo includes southern South America . It occurs from the extreme west of Brazil through the southeast of Bolivia , the west and northwest of Paraguay to Argentina and eastern Chile , the main distribution area is Argentina to the southern tip of the continent. The armadillo species reached the extreme western refuges in Chile relatively late; the first evidence dates from the 19th century. Early finds were recorded from the Región del Bío-Bío in the central part of the country; first observations were made in the 1970s from the areas far south near the Strait of Magellan . The entire distribution area covers 2.53 million square kilometers, but the population density is unknown. In Uruguay , the big hairy armadillo is not native despite similar climatic conditions here probably had the water barrier of the Río de la Plata as a diffusion barrier. Smaller populations were introduced on the Great Tierra del Fuego Island from 1982 as a food resource for the workers on the oil production sites, but these groups multiplied rapidly and by 2005 were already spread over more than 480 km². The habitats are often open, dry to semi-desert landscapes, so it occurs in the dry forests and thorn bush savannas of the Gran Chaco , as well as in the mountain shrub steppes of Patagonia and in the grasslands of the pampas . Occasionally the armadillo species is also observed in agricultural regions. Lowlands are largely inhabited, but the brown-bristle armadillo has also been detected up to 1500 m above sea level. The population density has hardly been investigated so far, for Bolivia there are data of about 0.58 animals per square kilometer, in Argentina it can be up to 200 individuals in individual areas over a comparable area. In parts of the distribution area, the armadillo lives sympatric with the small bristle armadillo ( Chaetophractus vellerosus ) and the six-banded armadillo ( Euphractus sexcinctus ).

Way of life

Territorial behavior

The brown-bristle armadillo is both diurnal and nocturnal and mostly solitary, but it also occurs in pairs. It lives partly underground in self-dug structures, which are occasionally built in close proximity to human settlements. These have a leeward entrance of up to 20 cm wide and 15 to 20 cm high and lead diagonally into the ground, but continue to run horizontally further underground. Different construction types are known: In soft, sandy soil, the constructions are relatively simple and reach around 50 cm deep into the ground, with a length of up to 70 cm. These simple caves are often used to procure food and protect against predators . Much more complex structures can be found in harder, often chalky subsoil and are around 1 m deep and up to 4.9 m long. These partly consist of several, sometimes star-shaped corridors and chambers. The chambers themselves are 20 to 30 cm long and 50 cm high. The brown-bristle armadillo uses such burrows as permanent habitation or to raise young, whereby these are created in areas that are not threatened by flooding. The armadillo also uses both types of construction for sleeping, which is done in the supine or lateral position, whereby a maximum of six hours are spent sleeping.

nutrition

The brown bristle armadillo is an omnivore . Investigations of gastrointestinal contents showed fruit to be over 60% , especially of the plants native to the dry Chaco region such as Caesalpinien , Prosopis , Ziziphus and Sideroxylon , but also of cacti such as Quiabentia . The remainder consists mainly of insects , especially termites and ants , but also grasshoppers and beetles such as ground beetles and weevils . The amount of plant and animal food consumed fluctuates and is probably dependent on the seasons , so more insects are consumed in winter than in summer. However, observations have shown that the armadillo can ingest carrion and is sometimes seen on cadavers or waste. It also actively preyes on smaller vertebrates such as amphibians and reptiles ; an occasionally postulated hunt for lambs has not yet been confirmed. In areas with more densely populated areas, the brown-bristle armadillo hunted for egg clutches from chickens , as well as those of the rhea . It searches for food with its head bowed low, close to the ground, and sometimes its head swings to one side. The sense of smell plays a major role here; after tracking down the prey, the brown-bristle armadillo digs it up rapidly with its front legs. It is known that the armadillo species can do without water for a long time, which is a prerequisite for survival in the dry areas.

Reproduction

The pairing occurs mainly from November to May Males court females by sniffing their genitals . The gestation period lasts about 60 to 75 days. As a rule, two young animals, usually a male and a female animal, are born. The birth itself takes about 10 minutes and takes place in a hiding place. The young animals have a very soft, leather-like shell that hardens as they grow. In addition, the mouth and eyes are completely closed except for the foremost area. The weight of a newborn is around 117 to 155 g. The eyes only open after 16 to 30 days, at which time the young animal leaves the hiding place for the first time, from the 35th day onwards it also begins to eat solid food. In total, a young will be suckled for around two months, during which time it will gain up to 1.5 kg. After the end of the suckling phase, the mother is ready for a new fertilization , the interval between individual births is 72 to 74 days. Young brown-bristle armadillos are sexually mature at nine months. The maximum service life is 20 years.

Predator and enemy behavior

The puma and jaguar in particular are predators of the brown-bristle armadillo; the armadillo is also occasionally hunted by foxes , but these mostly produce young animals. Since the 1990s, there has been an increase in hunting by the big cats, which may be related to the decline in the Viscacha population, which is actually the main prey. The brown-bristle armadillo is occasionally prey to dogs in areas populated by humans . When threatened, an animal gets up on its hind legs with the help of its tail sniffing before it runs away in zigzag lines or goes to a burrow. It can also dig in relatively quickly in the event of danger. Another known threat behavior is that an animal assumes a bent position with the help of the armor's movable straps and anchors its feet in the ground with its claws; in this position it is difficult to move by predators.

Parasites

The Amblyomma tick is known as an external parasite and infects the brown-bristle armadillo in several species. Fleas such as Tunga and Phthiropsylla are also documented, the former genus was found in 25% of all brown-bristle armadillos examined in eastern Argentina. Internal parasites mainly include roundworms . Representatives of the genera Aspidodera , Orihelia , Trichohelix and Mazzia often appear here . In addition, the armadillo is known as the host of the roundworm Trichinella , which can cause trichinosis in humans by consuming raw meat .

Systematics

Internal systematics of the armadillos according to Gibb et al. 2015   Dasypoda     Dasypodidae    Dasypus   Chlamyphoridae     Euphractinae    Euphractus sexcinctus      Chaetophractus villosus      Zaedyus pichiy      Chaetophractus vellerosus       Chlamyphorinae    Chlamyphorus      Calyptophractus   Tolypeutinae    Priodontes      Tolypeutes      Cabassous

The brown bristle armadillo belongs to the genus of the bristle armadillos ( Chaetophractus ), which includes another species. The bristle armadillos are members of the group of armadillos (Dasypoda), within this they are placed in the family of Chlamyphoridae and the subfamily of Euphractinae . In addition to the bristle armadillos, the Euphractinae also consist of the six-banded armadillo ( Euphractus ) and the dwarf armadillo ( Zaedyus ). The subfamily forms the sister group of a clade consisting of the Chlamyphorinae with the girdle mole and the Tolypeutinae , which also includes the spherical armadillos ( Tolypeutes ) and the bare- tailed armadillos ( Cabassous ). The division of the Chlamyphoridae into the three subfamilies that exist today began as early as the Upper Eocene 37 million years ago. The greater diversification of the Euphractinae began in the Upper Miocene around 11 million years ago. There are no known subspecies of the brown-bristle armadillo.

The phylogenetic origin of the brown-bristle armadillo is possibly in the region of the pampas , where the oldest fossil finds are known to date , which come from Chapadamalal in the province of Buenos Aires , Argentina, and date to the middle Pliocene around 4 to 3.2 million years ago become. At the same time, they represent the oldest evidence of the genus Chaetophractus . Fossil remains from the region of the Río de la Plata have an early Pleistocene age, bone platelets from the Toropí formation in the Argentine province of Corrientes in Argentina , which is outside of today's range , come from the Young Pleistocene . Since the brown-bristle armadillo is adapted to rather dry climates, this could speak for such conditions during the last glacial period in Mesopotamia. It is possible that the armadillo only reached today's Patagonia after the temperature minimum of the last glacial period 16,000 years ago, which is indicated by the very high genetic variability of the populations in this region.

The first description was made by Anselme Gaëtan Desmarest in 1804 under the scientific name loricatus villosus , based on the report Le Tatou Velu by Félix de Azara on the brown-bristle armadillo, which he wrote in 1801 in the book Essais sur l'Histoire Naturelle des Quadrupèdes de la Province du Paraguay had published. The local Guaraní people refer to the brown-bristle armadillo as tatu poju'i , where poju refers to the needle-like claws on the forefoot and i means "small".

Threat and protection

Brown bristle armadillo in the Wrocław Zoo

In general, no major threats are known. The brown-bristle armadillo is occasionally used as a food resource by some indigenous peoples, especially in winter when the animal has larger fat reserves, but studies show that the amount consumed is less than 1% of the total biomass consumed per year. The tank also serves as a sound box for musical instruments such as the charango . In different areas, such as in Patagonia, the animal is considered unclean and a pest and carrier of various diseases, especially in agricultural areas. In addition, the armadillo is said to cause injuries in horses and cattle , which occasionally cause the burrows in the soft ground to collapse due to their weight. Animals are often killed in more densely populated areas in car accidents, and here they are also subject to hunting by dogs living in the wild. Due to its widespread use and an assumed increase in the population, the brown bristle armadillo is classified as “not endangered” ( least concern ) according to the IUCN . It is native to several protected areas. The animal is also one of the most common types of armadillos kept in zoos.

literature

• Mariella Superina and Agustín Manuel Abba: Chlamyphoridae (Chlamyphorid armadillos). In: Don E. Wilson and Russell A. Mittermeier (eds.): Handbook of the Mammals of the World. Volume 8: Insectivores, Sloths and Colugos. Lynx Edicions, Barcelona 2018, pp. 48-71 (p. 68) ISBN 978-84-16728-08-4

Individual evidence

1. ↑ ^{a b c d e f g h i j k l} Paul Smith: Greater hairy armadillo Chaetophractus villosus (Desmarest, 1808) Mammals of Paraguay 11, 2008, pp. 1-15
2. ↑ ^{a b c d e} Mariella Superina and Agustín Manuel Abba: Chlamyphoridae (Chlamyphorid armadillos). In: Don E. Wilson and Russell A. Mittermeier (eds.): Handbook of the Mammals of the World. Volume 8: Insectivores, Sloths and Colugos. Lynx Edicions, Barcelona 2018, pp. 48-71 (p. 68) ISBN 978-84-16728-08-4
3. ↑ Silvia Margarita Squarcia, * Nora Silvia Sidorkewicj and Emma Beatriz Casanave: Cranial Osteology of the Armadillo Chaetophractus villosus (Mammalia, Xenarthra, Dasypodidae). International Journal of Morphology 24 (4), 2006, pp. 541-547
4. ↑ SM Squarcia, NS Sidorkewicj, R. Camina and EB Casanave: Sexual dimorphism in the mandible of the armadillo Chaetophractus villosus (Desmarest, 1804) (Dasypodidae) from northern Patagonia, Argentina. Brazilian Journal of Biology 69 (2), 2009, pp. 347-352
5. ^ SF Vizcaíno and N. Milne: Structure and function in armadillo limbs (Mammalia: Xenarthra: Dasypodidae). Journal of Zoology 257, 2002, pp. 257, 117-127
6. ↑ ^{a b} Sebastián Poljak, Julieta Sánchez, Lucas Lanusse and Marta Susana Lizarralde: Anthropogenic invaders: historical biogeography, current genetic status and distribution range of the “peludo” Chaetophractus villosus (Xenarthra) in Patagonia and Tierra del Fuego, southern South America. Mammalia, 2020, doi: 10.1515 / mammalia-2019-0076
7. ↑ Agustín. M. Abba and M. Superina: Chaetophractus villosus. Edentata 11 (2), 2010, p. 152
8. ^ ^{A b} Agustín M. Abba, Marcela J. Nabte and Daniel E. Udrizar Sauthier: New Data on Armadillos (Xenarthra: Dasypodidae) for Central Patagonia, Argentina. Edentata 11 (1), 2010, pp. 11-17
9. ↑ Agustín M. Abba, Daniel E. Udrizar Sauthier and Sergio F. Vizcaíno: Distribution and use of burrows and tunnels of Chaetophractus villosus (Mammalia, Xenarthra) in the eastern Argentinean pampas. Acta Theriologica 50 (1), 2005, pp. 115-124
10. ↑ Sergio F. Vizcaíno and Gerardo De Iuliis: Evidence for Advanced Carnivory in Fossil Armadillos (Mammalia: Xenarthra: Dasypodidae). Paleobiology 29 (1), 2003, pp. 123-138
11. ↑ Aldo Arriagada, Luisa Baessolo, Cristián Saucedo, Julio E. Crespo, Julio Cerda, Luis Parra, Dennis Aldridge, Jaime Ojeda and Alex Hernández: Hábitos alimenticios de poblaciones periféricas de Zaedyus pichiy y Chaetophractus chamypulagoniae, chlamypulidae en . Iheringia. Série Zoologia 107, 2017, p. E2017013, doi: 10.1590 / 1678-4766e2017013
12. ↑ Mariella Superina and Loughry WJ: Life on the Half Shell: Consequences of a carapace in the Evolution of Armadillos (Xenarthra: Cingulata). Journal of Mammal Evolution 19, 2012, pp. 217-224
13. ↑ María Julieta Olocco Diz and Ana Duggan: The First Hand-Rearing of Larger Hairy Armadillos (Chaetophractus villosus) at the Temaikèn Foundation. Edentata 6, 2004, pp. 27-30
14. ↑ ^{a b} Gillian C. Gibb, Fabien L. Condamine, Melanie Kuch, Jacob Enk, Nadia Moraes-Barros, Mariella Superina, Hendrik N. Poinar and Frédéric Delsuc: Shotgun Mitogenomics Provides a Reference Phylogenetic Framework and Timescale for Living Xenarthrans. Molecular Biology and Evolution 33 (3), 2015, pp. 621-642
15. ↑ Maren Möller-Krull, Frédéric Delsuc, Gennady Churakov, Claudia Marker, Mariella Superina, Jürgen Brosius, Emmanuel JP Douzery and Jürgen Schmitz: Retroposed Elements and Their Flanking Regions Resolve the Evolutionary History of Xenarthran Mammals (Armadillos, Anteaters and Sloths). Molecular Biology and Evolution 24, 2007, pp. 2573-2582.
16. ↑ Frederic Delsuc, Mariella Superina, Marie-Ka Tilak, Emmanuel JP Douzery and Alexandre Hassanin: Molecular phylogenetics unveils the ancient evolutionary origins of the enigmatic fairy armadillos. Molecular Phylogenetics and Evolution 62, 2012, 673-680
17. ↑ Esteban Soibelzon, Ángel Ramón Miño-Boilini, Alfredo Eduardo Zurita and Cecilia Mariana Krmpotic: Los Xenarthra (Mammalia) del Ensenadense (Pleistoceno inferior a medio) de la Región Pampeana (Argentina). Revista Mexicana de Ciencias Geológicas 27 (3), 2010, pp. 449-469
18. ^ Analía Francia and Martín R. Ciancio: First record of Chaetophractus villosus (Mammalia, Dasypodidae) in the late Pleistocene of Corrientes Province (Argentina). Revista del Museo de La Plata, Sección Paleontología, 13 (70), 2013, pp. 1-9
19. ↑ Sebastián Poljak, Viviana Confalonieri, Mariana Fasanella, Magalí Gabrielli and Marta Susana Lizarralde: Phylogeography of the armadillo Chaetophractus villosus (Dasypodidae Xenarthra): Post-glacial range expansion from Pampas to Patagonia (Argentina). Molecular Phylogenetics and Evolution 55 (1), 2010, pp. 38-46
20. ↑ Augusín M. Abba and Mariella Superina: Chaetophractus villosus. In: IUCN: IUCN Red List of Threatened Species. Version 2012.2. ( Online ), last accessed February 2, 2013

Web links

Commons : Chaetophractus villosus  - Collection of images, videos and audio files

• Chaetophractus villosus in the endangered Red List species the IUCN 2006. Posted by: Abba & Superina, 2006. Retrieved on February 2, 2013.