Size

• The American Kennel Club limits long-haired Chihuahuas from participating in dog shows if they are larger than six pounds. This does not mean that Chihuahuas are always less than six pounds. A full grown purebred Chihuahua can weigh up to 12 pounds, and placing it next to a teacup-sized three pound long-haired Chihuahua can lead people to believe they are completely different types.
  
  

Coloring

• The long-haired Chihuahua can be a multitude of colors. They can be white, light brown, gray or black. The patterns and spotting on the coat can sometimes be mistaken for another breed altogether. Some long-haired Chihuahuas have one color fur, while others have stripes or segments of one color or another.
  
  

Head Shape

• Two head shapes exist on the long-haired Chihuahua--deer-shaped and apple-shaped. The apple shape is domed and round and the forehead protrudes outwards. The deer-shaped long-haired Chihuahua has a more slender head with a longer nose, resembling a deer. The "Taco Bell" dog has a deer-shaped head. Although there is nothing wrong with the health of a long-haired Chihuahua with a deer-shaped head, the American Kennel Club does not accept the deer-shaped head for dog shows, stating that it is not the breed standard.
  
  

Ears

• The long-haired Chihuahua has large ears for its size. The ears can stand upright or fall over. The breed standard is for the ears to perk up and trainers and owners often train their Chihuahua's ears to stand correctly.
  
  

Height

• A long-haired Chihuahua will usually stand six to nine inches tall. Some larger Chihuahuas will be much larger, up to 15 inches tall. These pups are rare and will certainly cause some confusion with Chihuahua owners.
  
  

Similar Breeds

• Long-haired Chihuahuas regularly get confused with other dog breeds such as the Papillion and Pomeranian. The Papillion has similar coloring, size, height and ears, although they usually stand taller and weigh more than a long-haired Chihuahua. Pomeranians often have more fur than a long-haired Chihuahua, but that doesn't stop people from mixing the two up regularly. Also, "Pomchis," or Pomeranian and Chihuahua mixes, can be confusing to the observer, as the dog may have characteristics of both breeds.