AbstractThe Campanian rudist fauna identified from the localities Playa Panamá, Santa Rosa National Park, Colorado de Abangares, and Bolsón in Guanacaste Province, Costa Rica, is composed of the antillocaprinidsAntillocaprinasp. aff.A. suboccidentalisChubb, 1967,Antillocaprinasp. and Antillocaprinidae indet.; the multiple-fold hippuritidsBarrettia moniliferaWoodward, 1862,Parastroma trechmanniChubb, 1967, and cf.Whitfieldiella gigas(Chubb, 1955); the plagioptychidsPlagioptychus trechmanniChubb, 1956,Plagioptychussp. cf.P. zansiChubb, 1956,Mitrocaprina costaricaensisnew species,Mitrocaprina multicanaliculataChubb, 1956, and Plagioptychidae indet.; and the radiolitidsRadiolitessp. aff.R. multicostata(Adkins, 1930),Alencasteritesnew genusmooretownensis(Trechmann, 1924),Bournonia?tetrahedron(Chubb, 1967),Chiapasellasp.,Guanacastea costaricaensisnew genus new species, cf.Potositessp. aff.P. tristantorresiAlencáster and Pons in Pons et al., 2010, and aff.Thyrastylonsp. Although some differences in rudist diversity and sedimentary setting were observed among localities, most species indicate the same age for all occurrences, which correspond to the Campanian, probably mid-Campanian. Radiolitid specimens appear better preserved than those of other taxa and are thus discussed more in detail. Both the number of radiolitid genera exclusively known from the New World, and reasonable doubts about the correct attribution of some New World species to Old World genera, indicate important differences between rudist faunas at both sides of the Atlantic (Mediterranean and American Tethys, respectively) during the Late Cretaceous.
Isotopic evidence for changes in the zinc cycle during Oceanic Anoxic Event 2 (Late Cretaceous)
