The Terceira Mastiff comes from the isle of Terceira, located in the Azores. It descends from local dogs, old Spanish and English mastiffs and bulldogs, the Dogue de Bordeaux and the Bloodhound. According to a legend, it once was very popular among the pirates of the region and soon became a popular fighting dog as well. In the 1880s, veterinarian Dr. Jose Leite Pacheco wrote the first breed standard and intended to make the nickname rabo torto as the official name of the breed instead of the cão de fila da Terceira. Unfortunately, the Terceira Mastiff was already extremely endangered that time, which was one of the reasons why - despite of the Portuguese standard - it was never accepted by the FCI.
In the 1960s, the breed was tried to be revived with the aid of the Portuguese government. However, there was disagreement between politics and breeders, which led to the failure of the project. After this, the future of the Terceira Mastiff depended solely on the local farmers and fanciers of the breed. In the 1970s, it was already stated to be extinct, although there were still some individuals left in the Azores. With these few individuals, the recreation of the breed finally begun.
The Terceira Mastiff is a medium-sized molosser that represents the Fila or Dogo type and resembles the Cão Fila de São Miguel. One of its most remarkable features is an innately short, corkscrew like tail. Its nose can be either black, pink, or even brown. The colour of the short, smooth coat can be either fawn or yellow, always with a light mask. Red, brindle, and black individuals are usually considered to be unpure. The height is approximately 55 cm (22 in).