Les gangas (Aves, Columbiformes, Pteroclidae) du Paléocène et du Miocène inférieur de France.

Cécile Mourer-Chauviré

The two species of Sandgrouse from Quercy, Pterocles validus MILNE-EDWARDS and P. larvatus MILNE-EDWARDS, are ascribed to the genus Archaeoganga MOURER-CI-IAUVIRÉ which includes a third, very large species, A. pinguis. The sandgrouse of Saint-Gérand-le-Puy, Pterocles sepultus MILNE-EDWARDS, is ascribed to a new genus, Lepzoganga. This form appears in the Upper Oligocene of Quercy, in Pech Desse and Pech du Fraysse localities, and is still present in the Lower Miocene of Saint-Gérand-le-Puy and Paulhiac. Recent sandgrouse live in semidesert or desert areas. The indications provided by mammal and bird faunas in the localities where sandgrouse were found, confirm that the paleoenvironment was open and arid. The morphological study of these fossils indicates that, in the Upper Eocene, the Pteroclidae were already completely individualized with respect to Charadriiformes.