Additions to continental gastropods from the Upper Cretaceous and Paleocene of NE Mexico

Abstract

Additions are offered to the diverse estuarine, freshwater and terrestrial gastropod fauna of the Upper Cretaceous (Campanian) and Paleocene lithostratigraphic units of the Difunta Group, NE México (Coahuila and Nuevo León). Nineteen species of continental gastropods (five of them new) are reported and illustrated from the upper Campanian Cerro del Pueblo Formation (Las águilas/Porvenir de Jalpa locality) and the Paleocene Las Encinas Formation (La Leona locality), northern Parras Basin, Difunta Group, Coahuila. The first record of pulmonate gastropods from the Difunta Group is based on several specimens of different species. This is the third contribution dealing with these continental gastropods from the study region and a revised list of reported species is presented. Although we follow the most recent classification of continental gastropods, we also base the identification on paleontological systematics, knowing that some important diagnostic features were not preserved. Thus, we do not intend to propose paleobiogeographic or evolutionary inferences. Our main goal is to present the paleodiversity known from the study area, in hope that these data would be useful for more detailed studies in the near future.