New species of 10-tonne dinosaur discovered on the Iberian Peninsula

In 2007, during work on the Madrid-Levante high-speed railway line, fossils were collected of one of the last giants to inhabit Europe before the extinction of the dinosaurs. Qunkasaura pintiquiniestra is the name of the new species of dinosaur that lived on the Iberian Peninsula 73 million years ago.

"Qunkasaura is a sauropod dinosaur that lived on the Iberian Peninsula in the Upper Cretaceous. We know that this dinosaur lived in Cuenca and died there. It probably belonged to a group at least spread across the Iberian Peninsula, and this one in particular belonged to a lineage that we believe had a distribution that had affinities with other sauropod dinosaurs from European and Asian territory," explains Pedro Mocho.

The Portuguese palaeontologist, from the University of Lisbon's Dom Luiz Institute of the Faculty of Sciences, is part of the team that made the discovery, published in the journal Communications Biology.

The new species belongs to the sauropod group, which are distinguished by being large, long-necked and long-tailed herbivorous dinosaurs that are rare in the rest of Europe.

Qunkasaura pintiquiniestra stands out for being one of the most complete sauropod skeletons found in Europe. From this specimen found at the Lo Hueco site, it was possible to collect cervical, dorsal and caudal vertebrae, part of the pelvic girdle and elements of the limbs.

"We're talking about a specimen that would have been around 15 metres long, so head to tail, it could have weighed around ten tonnes and been three metres high up to the shoulder. But these animals, the sauropod dinosaur group, could reach much larger sizes," according to Mocho.

The presence of this specimen in Lo Hueco also suggests that this and other species moved between continents.

"For some reason, we have these groups of large dinosaurs living in a territory that at the time corresponded to an island. The Iberian Peninsula at that time was an island joined to the southern part of France. We call it the Ibero-Armorican island, which includes what is now part of Portugal, Spain and southern France," says the palaeontologist.

According to the researcher, in island situations, species tend to evolve to decrease in size because there is less availability of resources. It is on this basis that it is estimated that Qunkasaura did not evolve in Europe, but migrated from Asia to the Iberian Peninsula.

"In this territory there were already endemic groups, probably more than 20 million years old, that lived in isolation and in an insular environment, which is why we find small species today, not only in sauropod dinosaurs but also in other groups of dinosaurs and vertebrates."

In the case of this new lineage, says Mocho, it was possible to realise that it is related to two species from Asia and North America. Therefore, apart from their medium to large size, these species probably didn't evolve in isolation in this territory and didn't give rise to endemic species.

"These groups probably arrived in Europe from Asia and travelled through Eastern Europe until they reached the Ibero-Armorican island. This is because during this period of the Upper Cretaceous there are always times when the average sea level drops and rises and, therefore, at times when the average sea level drops, there is the possibility of the territories connecting with each other and, therefore, at that time we have some lineages capable of passing through this territory and others not," the researcher believes.

The name "Qunkasaura pintiquiniestra" comes from various geographical and cultural references close to the Lo Hueco deposit: "Qunka" refers to the oldest etymology of the toponym of the Cuenca and Fuentes area, "Saura" corresponds to the feminine of the Latin "saurus" (lizard) and honours the Spanish painter Antonio Saura, who died in Cuenca in 1998, and "pintiquiniestra" alludes to the "Queen Pintiquiniestra", a character from a novel quoted in Miguel Cervantes' "Don Quixote de la Mancha".

Part of the dinosaur's skeleton is now on display at the Castilla-La Mancha Palaeontology Museum in Cuenca.