New mollusc fossils from Buenache de la Sierra and las Hoyas (Lower Cretaceous, Cuenca, Spain)

Resumen presentado en las XXXVII Jornadas de Paleontología y en el V Congreso Ibérico de Paleontología.[EN] Periodic excavations over the last five years at Las Hoyas and preliminary prospections in new sites at Buenache de la Sierra (Cuenca, Spain) have yielded new records of molluscs from the La Huérguina Fm. (upper Barremian). Previous studies of the micro and macro fauna have focused on mostly juvenile elements of some species. This new record of the macrofauna completes and advances these studies previously published by the authors. It is confirmed that the bivalve species found in the new Buenache de la Sierra sites, are the same as those found in the Las Hoyas: “Unio” cf. turgidulus, “Unio” elongatus and “Unio”sp. A. Belonging to the Unionoidea (Unionida) they are preserved as composite moulds, most of them articulated. With respect to the gastropods from Buenache de la Sierra, of which we previously had only microfaunal remains coming from different outcrops than the ones studied here, we have identified Viviparus sp. (Viviparidae), Prophysa sp. (Pulmonata) and Paraglauconia cf. fittoni (Cassiopidae), which, with the exception of the Viviparus sp. are preserved as internal moulds. The last taxon is interesting because it could indicate a change in the salinity of the ecosystem.This is a contribution to the PID2019-104625RB-I00 project (Government of Spain).Peer reviewe