Sarcoptic mange has been reported in a wide range of mammals nationwide. In Michigan, sarcoptic mange has been reported in red fox, coyote, gray wolf, porcupine, black bear, cottontail rabbit, and raccoon. Notoedric mange has been reported in North America and in Michigan in the eastern fox squirrel and the gray (black) squirrel. There is some question as to the specificity of the mites causing mange on the various species of wildlife. Some parasitologists believe the mite is specific for the host on which it is found. Other parasitologists challenge this belief because there are records of transfer from fox to wolf and dog, rabbit to monkey, goat to man, dog to man, etc. It appears that sarcoptic mange mites are less host-specific than originally believed allowing for an infestation to occur on a dog that has contact with a mangy wild canid. Notoedric mange mites are host specific for squirrels and are not transmissible to either canid or feline pets.
Transmission and Development
Sarcoptic and notoedric mange mites spread to new hosts through direct body contact or by transfer from common nests and burrows. Stages in the life cycle include the egg, larva, 2 nymphs and the adult. The parasite lives and burrows in the skin layers. Fertilized females deposit eggs as they tunnel through the skin, and the eggs hatch in 3 to 4 days. Males complete their development in 13 to 16 days, females in 18 to 23 days. Fertilization apparently takes place when the female is in its final stage of development.
http://www.michigan.gov/dnr/0,1607,7-153-10370_12150_12220-26949--,00.html

Evidently, it's a fairly common problem.
http://www.nps.gov/fiis/Mange.htm

It's pretty ugly and I can see why the animal is not easily identified. One thing I have a question about–the teeth on the original dead "unusual" animal. Somehow, they look faked-like the photo has been altered, maybe to make it look a little stranger that it already does.
P