FIRST RECORD OF A GIANT BIRD FROM THE LATE MAASTRICHTIAN OF THE TREMP BASIN (SOUTHERN PYRENEES, SPAIN)

M. PÉREZ-PUEYO; JOSÉ MANUEL GASCA; MIGUEL MORENO-AZANZA; JOSÉ IGNACIO CANUDO; PENÉLOPE CRUZADO CABALLERO; EDUARDO PUÉRTOLAS-PASCUAL

Bruselas

Congreso; XVII Annual Meeting of the European Association of Vertebrate; 2019

The bird fossil record from the Upper Cretaceous of Europe is scarce and fragmentary. Nonetheless, some enantiornithean remains (e.g. Martinavis cruzyensis) have been found, and most remarkably, the remains of the giant bird Gargantuavis philoinos from the lower Maastrichtian of France, which has an uncertain position among Aves. To this day, however, no bird remains from the upper Maastrichtian have been recovered on the Ibero-Armorican Island. Here we present a cervical vertebra (MPZ 2019/264) belonging to a large-sized bird recovered from the fossil locality ?Dolor 3? (Tremp Fm: Maastrichtian-Danian) near the village of Serraduy (Huesca Province, NE Spain). The Tremp Fm deposits from this area are dated to within Chron C29r, therefore MPZ 2019/264 is the youngest Mesozoic Aves fossil occurrence for the Ibero-Armorican Island, and the first report of this animal clade from the Tremp Basin. MPZ 2019/264 is a moderately well-preserved elongated vertebra with some weathered and eroded parts, lacking the caudal articular face. Nevertheless, the morphology of the cranial articular face (concave transversely-convex dorsoventrally) confirms an advanced heterocoelous condition. The vertebra is strongly pneumatized, bearing two lateral pneumatic foramina in the neural arch and another one in the centrum. This feature along with a low and anteroposteriorly elongated neural spine and the arrow-shaped section of the centrum, differentiate MPZ 2019/264 from the cervical vertebra from Montplo-Nord (France), referred to Gargantuavis. This implies the presence of a second taxon of giant bird on the Ibero Armorican Island on the last few hundred thousand years before the K/Pg extinction.