The Azteca is a horse breed from Mexico, with a subtype, called the "American Azteca", found in the United States. They are well-muscled horses that may be of any solid color, and the American Azteca may also have Paint coloration. Aztecas are known to compete in many western riding and some English riding disciplines. The Mexican registry for the original Azteca and the United States registries for the American Azteca have registration rules that vary in several key aspects, including ancestral bloodlines and requirements for physical inspections. The Azteca was first developed in Mexico in 1972, from a blend of Andalusian, American Quarter Horse and Mexican Criollo bloodlines. From there, they spread to the United States, where American Paint Horse blood was added. Breed characteristics The three foundation breeds of the Azteca are the Andalusian (defined by the Mexican registry as either Pura Raza Española or Lusitano), American Quarter Horse, and Mexican Criollo or Criollo militar. They were chosen to produce a breed that combined athletic ability with a good temperament and certain physical characteristics. Azteca stallions and geldings measure between at the withers, while mares stand between . The ideal height is . Both sexes usually weigh from . The facial profile of the breed is straight or convex and the neck slightly arched. Overall, they are well-muscled horses, with broad croup and chest, as well as long, sloping shoulders. Gaits are free and mobile, with natural collection derived from the Andalusian ancestry of the breed. The breed is found in all solid colors, although gray is most often seen. White markings are allowed on the face and lower legs by breed associations. The American Azteca registry also allows non-solid pinto coloration. Registration According to the breed standard of the Mexican registry, Azteca horses cannot have more than 75 percent of their parentage from any one of the foundation breeds (Andalusian, Quarter Horse and Mexican Criollo); Criollo blood may be no more than 50%, and only from unregistered mares within Mexico. Horses are classified in one of six registration categories, designated with letters A through F, depending on their parentage. Only certain crosses between the different classes are permitted. In Mexico, Azteca horses must conform to a strict phenotype standard established by the Secretaría de Agricultura, Ganadería, Desarrollo Rural, Pesca y Alimentación (SAGARPA), the Mexican agriculture ministry, which requires inspection of foals at seven months for the issue of