Mid-Cretaceous turnover of saurischian dinosaur communities: evidence from the Neuquén Basin

Successional changes are recorded among saurischian dinosaur faunas throughout the Cretaceous of the Neuquén Basin. Both sauropod and theropod lineages present in NW Patagonia show comparable transformations and indicate that some clades did not survive the Late Turonian boundary. Similar patterns of changes are observed in other Patagonian sedimentary basins. Diplodocoid sauropods and carcharodontosaurid theropods are not yet recorded in levels younger than Turonian, while titanosaurians and abelisauroids are present before and after this period. Important floral changes during the mid-Cretaceous, mainly related to the proliferation of angiosperms, could be one element that influenced some dinosaurian associations.