Pilmatueia

Pilmatueia is a genus of diplodocoid sauropods belonging to the family Dicraeosauridae that lived during the Early Cretaceous in what is now Argentina. Its type and only species is Pilmatueia faundezi. Pilmatueia was probably closely related to other South American dicraeosaurids such as Amargasaurus. Like other dicraeosaurids, Pilmatueia was relatively small for a sauropod. The vertebrae of Pilmatueia were more extensively hollowed out by air sacs than in other dicraeosaurids, which otherwise were characterized by a reduction in the air sac system compared to other sauropods. Pilmatueia dates to the Valanginian, an age of the Cretaceous period for which dinosaur faunas are poorly known.

==Discovery and naming== Fossils of Pilmatueia faundezi were discovered in Neuquén Province, Argentina, at a site called Pilmatué. Fossil excavations at Pilmatué began in 2009, and the discovery of dicraeosaurid remains at Pilmatué was first announced in 2012, at a paleontology conference in Buenos Aires. In 2019, Rodolfo Coria and colleagues named the new genus and species Pilmatueia faundezi. The genus name refers to the Pilmatué locality, and the species epithet recognizes Ramón Faúndez, manager of the Museo Municipal de Las Lajas, who supported the excavation project. The discovery of Pilmatueia in the Valanginian, an age of the Early Cretaceous with poorly known dinosaur faunas, helped fill a gap in the dicraeosaurid fossil record between Jurassic dicraeosaurids and the later Amargasaurus.