The excavation campaign at the Monte Agudo paleontological site (Pombal, Portugal) Credit: Instituto Dom Luiz

Portuguese man accidentally uncovers a 25-metre-long dinosaur skeleton in his own backyard

Paleontologists in Portugal have unearthed the fossilized skeleton of what could be the largest dinosaur ever found in Europe.

The remains of what could be the largest dinosaur to be found in Europe are being uncovered in a backyard in Pombal, a city in the central region of Portugal. The remains, that could correspond to a sauropod dinosaur with approximately 12 meters high and 25 meters long, are now being studied by an international research team.

It all started in 2017. While carrying out construction work, the owner of a property in Pombal noticed the presence of several fragments of fossilized bones in his yard and contacted the research team, who carried out the first excavation campaign in that same year.

More recently, between 1 and 10 August, 2022, Portuguese and Spanish paleontologists working on the site have been unearthing what may be the remains of the largest sauropod dinosaur to be found in Europe. Sauropods are herbivorous, quadrupedal dinosaurs, with long neck and tails.

"It is not usual to find all the ribs of an animal like this, let alone in this position, maintaining their original anatomical position. This mode of preservation is relatively uncommon in the fossil record of dinosaurs, in particular sauropods, from the Portuguese Upper Jurassic," says Elisabete Malafaia, Postdoctoral researcher at the Faculty of Sciences of the University of Lisbon (Ciências ULisboa), Portugal.

The excavation campaign at the Monte Agudo paleontological site (Pombal, Portugal) resulted in the extraction of part of the fossilized skeleton of a large sauropod dinosaur. Credit: Instituto Dom Luiz (Faculty of Sciences of the University of Lisbon).

So far, an important set of elements of the axial skeleton has been collected from the site, which includes vertebrae and ribs of a possible brachiosaurid sauropod dinosaur. The Brachiosauridae group is composed of large species that lived from the Upper Jurassic to the Lower Cretaceous, approximately 160 to 100 million years ago, and are characterized by the presence of markedly developed forelimbs. Some of the most emblematic dinosaur species belong to this group of sauropods, such as Brachiosaurus altithorax and Giraffatitan brancai, as well as the Portuguese Late Jurassic species found in Portugal's West region, Lusotitan atalaiensis.

The preservation characteristics of the fossils and their disposition indicate the possible presence of other parts of the skeleton of this individual, a hypothesis that will be tested in future excavation campaigns in the deposit.

"The research in the Monte Agudo paleontological locality confirms that the region of Pombal has an important fossil record of Late Jurassic vertebrates, which in the last decades has provided the discovery of abundant materials very significant for the knowledge of the continental faunas that inhabited the Iberian Peninsula at about 145 million years ago," adds Elisabete Malafaia. 

The above story is based on materials provided by the University of Lisbon.