The Late Cretaceous Rudist Associations from the Pyrenean Basin

T Age determinations and correlations of Cretaceous carbonate platforms are often constrained when larger benthic foraminifera are absent. Rudist provide a potentially robust alternative framework for biozonation in shallow-marine and lagoonal settings. The study of rudists in the Pyrenees has a long tradition, beginning with pioneering works in the eighteenth century. Over time, a substantial body of detailed knowledge has accumulated on rudist paleoecology, taxonomy, and functional morphology. This abundant record permits their use as biochronological markers following the revision of more than 10,000 specimens from the collections housed at the Universitat Autònoma de Barcelona. Our detailed evaluation of rudist assemblages has led to the recognition of the following Late Cretaceous rudist associations: Middle and Late Cenomanian, Eartly and Middle Turonian (based on Iberian Chain data), Late Turonian, Coniacian, Santonian, terminal Santonian- Early Campanian, Early Campanian, Middle Campanian, Late Campanian, basal Maastrichtian and Maastrichtian. These associations are calibrated with new magnetostratigraphic data and strontium-isotope ages. Although rudist species may be rather endemic, correlations and evolutionary trends with both Atlantic and Tethyan groups can be established.ext here,