He contacted palaeontologists, who unearthed part of the dinosaur skeleton earlier this month and have been examining it ever since.
Sauropods have characteristically long necks and tails and are among the largest animals to have ever lived.
The fossils discovered at the Monte Agudo site in Pombal are thought to be those of a brachiosaurid who lived during the Upper Jurassic period.
The fact that the vertebrae and ribs were found at the same location and in the position they would have been in the dinosaur's anatomy is "relatively rare", Malafaia said.
The team may conduct more digs in the coming months at the site and in the surrounding area.
