There is only one Chihuahua breed of dog, but there are seven varieties of Chihuahuas within that breed. These varieties are called long-coat, smooth-coat, apple-head, deer-head, fawn, teacup and pear-head.
All varieties of Chihuahuas, with the exception of teacup Chihuahuas, have an average weight of 3-6 pounds. They are generally 6-9 inches tall at the shoulder and have a life span between 10 and 18 years. The Chihuahua is known as the smallest dog breed in the world and is one of the most feisty and energetic. Chihuahuas are notorious for barking and having very high energy, though much of this depends on how they are raised. Chihuahuas are friendly, loving and form close bonds with their owners.