The remains of a large flying reptile that roamed Earth’s skies 100 million years ago during the age of the dinosaurs have been uncovered by researchers.

The prehistoric creature is a pterosaur, a group of animals that appeared more than 200 million years ago and flourished until the mass extinction event around 66 million years ago—which wiped out their dinosaur relatives, in addition to many other forms of life.

Pterosaurs and dinosaurs both belong to a larger group known as the archosaurs, which also counts birds and crocodiles as members. Pterosaurs are notable for being the first vertebrates—or animals with backbones—to evolve flight capabilities

This week, a team of paleontologists announced the discovery of pterosaur remains from the province of Rio Negro in the Patagonia region of southern Argentina.

Illustration of a pterosaur

An illustration of the pterosaur represented by a single vertebra bone found on the banks of the Ezequiel Ramos Mexía Reservoir in Rio Negro Province, Argentina. This prehistoric reptile belongs to a group known as Azhdarchidae that includes the largest flying animals of all time. Gabriel Lio/Laboratorio de Anatomía Comparada y Evolución de los Vertebrados

Researchers found a single neck vertebra bone on the banks of the Ezequiel Ramos Mexía Reservoir—a huge man-made lake located along Rio Negro’s border with the neighboring province of Neuquén.