This mammal is found in open and semi-open habitats, especially grasslands with scattered bushes and trees, in south, central-west and south-eastern Brazil (Mato Grosso, Mato Grosso do Sul, Minas Gerais, Goiás, São Paulo, Federal District and recently Rio Grande do Sul), Paraguay, northern Argentina, Bolivia east and north of the Andes, and far south-eastern Peru (Pampas del Heath only). It is very rare in Uruguay, being possibly extirpated. IUCN lists it as near threatened, while it is considered vulnerable by the Brazilian government (IBAMA). It is the only species in the genus Chrysocyon. It is locally known as aguará guazú (meaning "large fox" in the Guarani language), lobo de crin, lobo de los esteros or lobo colorado, and as lobo-guará in Brazil. It is also called borochi in Bolivia.
The maned wolf has often been described as "a red fox on stilts" owing to its similar coloration and overall appearance, though it is much larger than a red fox and belongs to a different genus. The adult animal stands 67 to 107 cm (26 to 42 in) tall at the shoulder, averages 125 cm (49 in) in head-and-body length and weighs 20 to 34.09 kg (44 to 75.2 lb). The maned wolf is the tallest of the wild canids. The long legs are probably an adaptation to the tall grasslands of its native habitat. The tail measures 28 to 45 cm (11 to 18 in) in length. Fur of the maned wolf may be reddish brown to golden orange on the sides with long, black legs and a distinctive black mane. The coat is further marked with a whitish tuft at the tip of the tail and a white "bib" beneath the throat. The mane is erectile, and is typically used to enlarge the wolf's profile when threatened or when displaying aggression.
The maned wolf is also known for its distinctive odor, which has earned it the nickname "skunk wolf."
Hunting and territoriality
Unlike other large canids (such as the gray wolf, the African hunting dog, or the dhole) the maned wolf does not form packs. It hunts alone, usually between sundown and midnight. It kills its prey by biting on the neck or back, and shaking it violently if necessary. Monogamous pairs may defend a shared territory of about 30 km2 (12 sq mi), though the wolves themselves may seldom meet, outside of mating. The territory is crisscrossed by paths that the wolves create as they patrol at night. Several adults may congregate in the presence of a plentiful food source; a fire-cleared patch of grassland, for example, which would leave small vertebrate prey exposed to foraging.
Both male and female maned wolves use their urine to communicate, e.g. to mark their hunting paths, or the places where they have buried hunted prey. The urine has a very distinctive smell, which some people liken to hops or cannabis. The responsible substance is very likely a pyrazine, which occurs in both plants. (At the Rotterdam Zoo, this smell once set the police on a hunt for cannabis smokers.)
The mating season ranges from November to April. Gestation lasts 60 to 65 days, and a litter may have from 2 to 6 black-furred pups, each weighing about 450 g (16 oz). These pups are fully grown in about one year. During that year, the pups are known to rely on their parents for food.
The maned wolf specializes in small and medium-sized prey, including small mammals (typically rodents and hares), birds, and even fish. A large fraction of its diet (over 50%, according to some studies) is vegetable matter, including sugarcane, tubers, and fruit (especially the wolf apple, Solanum lycocarpum, a tomato-like fruit). Captive maned wolves were traditionally fed meat-heavy diets and developed bladder stones. Zoo diets now feature fruits and vegetables, as well as meat and dog chow.
Relations with other species
The maned wolf participates in symbiotic relationships with the plants that it feeds on, as it carries the seeds of various plants, and often defecates on the nests of leafcutter ants. The ants then use the dung to fertilize their fungus gardens, and later discard the seeds onto refuse piles just outside their nest. This process significantly increases the germination rate of the seeds. The wolf is particularly susceptible to infection by the giant kidney worm, a potentially fatal parasite that may also infect domestic dogs. The maned wolf is not a common prey species for any other predator, though it may be attacked or killed by feral domestic dogs.
Relations with humans
The maned wolf is said to be a potential chicken thief; it was once also considered a threat to cattle and sheep, though this is now known to be false. In Brazil, the animal was historically hunted down for some body parts, notably the eyes, that were believed to be good luck charms. Since its classification as a Vulnerable species by the Brazilian government, it has received greater consideration and protection from most people. They are also threatened by habitat loss and being run over by cars. Feral and domestic dogs attack them and pass on diseases to them. The maned wolf is generally shy and flees when alarmed, so it poses little direct threat to humans. It occurs in several protected areas, including the national parks of Caraça and Emas in Brazil. The maned wolf is well represented in captivity, and has been bred successfully at a number of zoos, particularly in Argentina.
Although the maned wolf displays many fox-like characteristics, it is not closely related to foxes and lacks the elliptical pupils found in foxes. The maned wolf's evolutionary relationship to the other members of the canid family makes it a unique animal. Electrophoretic studies did not link Chrysocyon with any of the other canids studied. One conclusion of this study is that the maned wolf is the only survivor of the late Pleistocene extinction of the large South American canids. Fossils of the maned wolf from the Holocene and the late Pleistocene have been excavated from the Brazilian Highlands. 
A study, published in 2003, on the brain anatomy of several canids, placed the maned wolf together with the Falkland Islands wolf, and with pseudo-foxes of the genus Pseudalopex. One study based on DNA evidence, published in 2009, showed that the extinct Falkland Islands wolf was the most closely related species to the maned wolf in historical times, and shared a common ancestor with it about 6 million years ago.
Its closest living relative is the bush dog (genus Speothos), with a more distant relationship to other South American canines (the short-eared dog, the crab-eating fox and the 'false foxes' or Pseudalopex).
The maned wolf is not closely related to any other living canid. It is not a fox, wolf, coyote, dog, or jackal, but a distinct canid, although previously it had been placed in Canis and Vulpes genera based on morphological similarities.
- Wozencraft, W. C. (2005). "Order Carnivora". In Wilson, D. E.; Reeder, D. M. Mammal Species of the World (3rd ed.). Johns Hopkins University Press. pp. 532–628. ISBN 978-0-8018-8221-0. OCLC 62265494. http://www.bucknell.edu/msw3/browse.asp?id=14000790.
- Rodden, M., Rodrigues , F. & Bestelmeyer, S. (2008). Chrysocyon brachyurus. In: IUCN 2008. IUCN Red List of Threatened Species. Retrieved 22 March 2009. Database entry includes justification for why this species is near threatened.
- Osgood, Wilfred H. (1919). "Names of Some South American Mammals". Journal of Mammalogy 1 (1): 35. doi:10.2307/1373718. JSTOR 1373718.
- Langguth, A. (1975). "Ecology and evolution in the South American canids". In M. W. Fox, ed.. The wild canids: their systematics, behavioral ecology and evolution. New York: Van Nostrand Reinhold Company. pp. 192–206. ISBN 0442224303.
- Sillero-Zubiri, Hoffmann, & Macdonald (eds). 2004.Canids: Foxes, Wolves, Jackals and Dogs – 2004 Status Survey and Conservation Action Plan. IUCN/SSC Canid Specialist Group.
- Dietz, J. M. (1984). "Ecology and social organization of the maned wolf (Chrysocyon brachyurus)". Smithsonian Contributions to Zoology 392 (392): 1–51. doi:10.5479/si.00810282.392.
- Maned wolf. Houston Zoo
- Boitani, Luigi, Simon & Schuster's Guide to Mammals. Simon & Schuster/Touchstone Books (1984), ISBN 978-0-671-42805-1
- Dietz, James (1984). Macdonald, D.. ed. The Encyclopedia of Mammals. New York: Facts on File. p. 31. ISBN 0-87196-871-1.
- Burnie D and Wilson DE (Eds.), Animal: The Definitive Visual Guide to the World's Wildlife. DK Adult (2005), ISBN 0789477645
- Cristian Frers. "Un lobo de crin llamado Aguará Guazú". http://www.internatura.org/estudios/informes/lobo.html. Retrieved 2007-04-23.
- Brian Switek (2011-03-10). "Maned Wolf Pee Demystified". Wired. http://www.wired.com/wiredscience/2011/03/maned-wolf-pee-demystified/. Retrieved 2011-06-05.
- Süddeutsche Zeitung, 2006-09-02, p3
- Juarez, Keila Macfadem; Jader Marinho-Filho (November 2002). "Diet, habitat use, and home ranges of sympatric canids in central Brazil". Journal of Mammalogy 83 (4): 925–934. doi:10.1644/1545-1542(2002)083<0925:DHUAHR>2.0.CO;2.
- Motta-Junior, J. C., S. A. Talamon, J. A. Lombardi, AND K. Simokomaki (1996). "Diet of maned wolf, Chrysocyon brachyurus, in central Brazil". Journal of Zoology (London) 240 (2): 277–284. doi:10.1111/j.1469-7998.1996.tb05284.x.
- Courtenay, O. (1994). "Conservation of the Maned Wolf: fruitful relationships in a changing environment". Canid News 2. http://www.canids.org/PUBLICAT/CNDNEWS2/manedwf2.htm.
- Lyras, G.A., Van der Geer, A.A.E. 2003. External brain anatomy of the Canidae. Zoological Journal of the Linnean Society 138: 505–522. London. doi:10.1046/j.1096-3642.2003.00067.x
- New Clues To Extinct Falklands Wolf Mystery. Sciencedaily.com (2009-11-03). Retrieved on 2012-12-20.
- Kerstin, Lindblad-Toh; Claire M Wade, Tarjei S. Mikkelsen, Elinor K. Karlsson, David B. Jaffe, Michael Kamal, Michele Clamp, Jean L. Chang, Edward J. Kulbokas III, Michael C. Zody, Evan Mauceli, Xiaohui Xie, Matthew Breen, Robert K. Wayne, Elaine A. Ostrander, Chris P. Ponting, Francis Galibert, Douglas R. Smith, Pieter J. deJong, Ewen Kirkness, Pablo Alvarez, Tara Biagi, William Brockman, Jonathan Butler, Chee-Wye Chin, April Cook, James Cuff, Mark J. Daly, David DeCaprio, Sante Gnerre, Manfred Grabherr, Manolis Kellis, Michael Kleber, Carolyne Bardeleben, Leo Goodstadt, Andreas Heger, Christophe Hitte, Lisa Kim, Klaus-Peter Koepfli, Heidi G. Parker, John P. Pollinger, Stephen M. J. Searle, Nathan B. Sutter, Rachael Thomas, Caleb Webber (2005-12-08). "Genome sequence, comparative analysis and haplotype structure of the domestic dog". Nature 438 (7069): 803–819. doi:10.1038/nature04338. PMID 16341006.
- Lindblad-Toh et al.; Wade, CM; Mikkelsen, TS; Karlsson, EK; Jaffe, DB; Kamal, M; Clamp, M; Chang, JL et al. (2005). "Genome sequence, comparative analysis and haplotype structure of the domestic dog". Nature 438 (7069): 803-819. doi:10.1038/nature04338. PMID 16341006. http://www.nature.com/nature/journal/v438/n7069/pdf/nature04338.pdf.