Morphological study of the muscles of the forearm of the short-eared dog (Atelocynus microtis) and crab-eating fox (Cerdocyon thous)

Atelocynus microtis and Cerdocyon thous are mammals in the Canidae with different habits and geographical distributions. The fi rst species is found in the Amazon Basin in Brazil, Peru, Colombia, Ecuador and Venezuela, and probably lives a nocturnal and solitary life. The second species occurs in Colombia, Venezuela, Suriname, Bolivia, Paraguay, Uruguay, Brazil and northern Argentina, is also nocturnal, but forms couples that tend to stay together for a long time. There is a lot of interest in understanding more about these animals, which have a wide distribution in Brazil, and morphological studies are an important contribution towards their preservation and protection because reports of short-eared dogs in captivity are rare, whereas those of the crab-eating fox are more common. In this study we used an individual of each species from Paragominas (PA), under the authorization permits SEMA-PA No. 455/2009 and 522/2009, which were donated to UFRA after the animals died of natural causes. The animals were fixed in 10% formalin and dissected to make morphological descriptions of the flexor and extensor muscles. This study found the same muscle groups that occur in other carnivores previously described, and contributes to understanding the morphology, as well as an approach for possible orthopedic surgical procedures, of these species.