I have seen them in person in the mexican city zoo
, but those had short coats like the red dog here File:Hairless and coated half.JPG - Wikipedia, the free encyclopedia
Acully the coated dogs are in the standar, however they can't be shown they are used for health in the breeding like the powderpuff of the chinese crested.
Originally Posted by FCI standar
Hairless variety : Due to the total absence of hair, the skin of this breed is of great importance. It is smooth, sensitive to touch and feels warmer because of direct heat emission due to the lack of hair; however its body temperature is the same as in other dogs with hair. The difference with haired breeds, which disperse body heat through natural ventilation, is that the skin requires more care from exposure to the sun and elements due to its lack of natural protection. Accidental scars are not penalized. The dog tends to sweat through its feet (foot pads and inter-digital membranes), which is why other than in extreme heat it seldom pants. It should be free of obvious skin problems.
Coated Variety : The skin of the coated Xoloitzcuintle is smooth and should be completely covered with hair.
Hairless variety : The characteristic of this breed is the total lack of hair on the body (hairless or nude dog) although there are some short, coarse thick hairs of any color on the forehead and back of the neck that should never be longer than 2.5 centimeters and should never form a long, soft topknot. It is common to find rough hair on the feet and on the end of the tail, however its absence should not be penalized.
Coated Variety : This variety of the Xoloitzcuintle has hair all over its body. It can be expected to have very little hair on its belly and inside the rear legs.