Also spelled fila brasiliero
A large dog, first bred in 16th century Brazil to hunt Jaguar, Wild Boar, and runaway slaves. It was the result of a cross-breed between the English Mastiff, Bulldog, Bloodhound, and Rafeiros. Of the four, the dog looks the most like the Mastiff, standing about 2-2.5 feet tall and weighing anywhere from 100 to over 200 pounds. The head also has the telltale wrinkles of a Bloodhound descendant.
The fila brasiliero is well known for its fierce loyalty to the family that owns it, and it is well known to be very patient around children. However, the breed is also known to be extremely suspicious of strangers. If the dog is not properly trained and socialized with humans, it may interpret an innocent pat on the back from an outsider as reason to attack. This paranoia has caused the breed to be specifically banned from entry into many countries.
Thanks to www.filadog.com for most of the info given here.