Anyone who tells you they have a teacup, micro, mini, toy, etc. Chihuahua is either Mis-Informed or LYING.
Its true. There is only one type of chihuahua, a chihuahua. According to the AKC breed standard (www.akc.org) there are two varieties of chihuahua, smoothcoat and longcoat... aside from that ALL chihuahuas should weigh 6lbs or less. That means that tiny little 2lb dog your neighbor has that they paid $2300 for because its an ultra micro mini teacup, is just a plain old regular chihuahua... probably just a runt. Anyone who tries to sell you a dog for ungodly amounts because it is a super toy teacup!!! ... is scamming you out of money. You need to do LOTS of research on these tiny dogs before you buy one. Do you really have a grasp on how small and fragile a 2lb dog is? Often these tiny little pups are born with many health defects, heart murmurs, liver shunts, 1 lung, 1 kidney, large open moleras in their skull... etc.
You can also read a fabulous article by the Chihuahua Club of America about their take on the teacup term HERE.
I, as a breeder, will not breed for these tiny little dogs. I prefer to stay within the higher spectrum of the breed standard, which is about the 4-6lbs range for females (so that they can safely deliver pups on their own without huge threat to their well-being), and 3-5 lbs for males. I take my dogs hiking and on outings so often that a tiny little dog would have issues keeping up without help... its just my personal preference.
Many breeders have lines of very small dogs that they have developed over many years who are health problem free. These breeders can only know this if they HEALTH TEST their dogs! They should NEVER market a dog as anything but a chihuahua. A reputable breeder has done enough research to know that there is no such thing as a teacup. If they choose to continue to use an incorrect term in order to market their dogs for more money, it is your choice to buy from them. If you are determined to own a tiny little chihuahua, PLEASE make sure your breeder tests for genetic defects (Heart Murmur and Luxating Patellas) and have the puppy thoroughly examined by a veterinarian before you purchase it. Get bloodwork done, make sure it has all the necessary organs to grow to adulthood and thrive. Do you want to bring this tiny little dog home only to find out 3 months later, after you're completely attached to it, that it has an inoperable health defect that will end its life before its a year old?
I cannot stress enough, when buying a tiny little dog... DO YOUR HOMEWORK! If you had no idea there was no such thing as a teacup chihuahua, have you researched them at all? Do you know about other issues chihuahuas can have? Genetic disorders? Hypoglycemia? What if you woke up one day and your dog was lethargic with pale gums and near death... and your vet is closed. Do you know what is happening? What to do? As a dog owner, you owe it to your dog to do at least enough research to be able to provide the best care possible to them. Chihuahuas are not your average dog, please make sure you know what you're getting into when you make the decision to bring one home.
Best wishes to all, and good for you for caring enough to educate yourself and read this article! :)
AKC Breed Standard - Chihuahua: http://www.akc.org/breeds/chihuahua/
Chihuahua Club of America - Teacup Statement: