Darwin-Bernissart meeting, Brussels, February 9-13, 2009 NEW EARLY CRETACEOUS MULTITUBERCULATE FOSSILS FROM THE IBERIAN PENINSULA Ainara BADIOLA, José Ignacio CANUDO, Gloria CUENCA-BESCÓS Universidad de Zaragoza, Ciencias de la Tierra (Área de Paleontología), Pedro Cerbuna, 12, 50009 Zaragoza, Spain. Grupo Aragosaurus (http://www.aragosaurus.com), [email protected], [email protected], [email protected] The most abundant and diverse fossils of multituberculate mammals are from the Early Cretaceous of Western Europe. They range from the Berriasian of Portugal and England up to the Barremian of Spain. Fossils of Valanginian age are scarce, and no Hauterivian multituberculates in Europe is reported. The Early Cretaceous multituberculate fossils from other areas of Laurasia and from Gondwana (Africa) are less diverse. New multituberculate finds have recently been described in the late Hauterivian-early Barremian of Spain, in the La Cantalera vertebrate locality, Teruel (Badiola et al. , 2008), and in a Barremian or Aptian locality from the Tetori Group of Japan (Kusuhashi, 2008). New Barremian specimens have also found in the Wessex Formation from England (Sweetman, in press). Here we report around sixteen new isolated teeth of the Valanginian/Hauterivian transition (the Pochancalo site, Villanueva de Huerva Fm.), the Hauterivian/Barremian transition (the Cantalera site, Blesa Fm.), and of the late Barremian (the Vallipón site, Artoles Fm.). These assemblages all come from the Aragonese branch of the Iberian Ranges (north-eastern of Spain). This work summarizes these new finds and updates the collection of isolated teeth (around twenty) from the Galve beds of Barremian age, previously described by Crusafont and Gibert (1976). The new discoveries that we report here increase the resolution of the multituberculate mammalian biostratigraphy and palaeobiogeography of these faunas during the Early Cretaceous in the Iberian Peninsula: an upper tooth found in Pochancalo-1 is assigned to the Albionbaataridae family, which represents the first early Hauterivian member in Europe and the first one in the Iberian Early Cretaceous assemblages; a new pinheirodontid taxon, Cantalera abadi Badiola et al. , 2008, has recently been described in the La Cantalera site, together with the oldest representative of the eobaatarid Eobaatar Kielan- Jaworowska et al. , 1987 and a taxon described as Plagiaulacidae or Eobaataridae gen. et sp. indet. The latter is also present in a site of Galve of the same age and probably belongs to a new taxon of the family Plagiaulacidae. If this assignment is correct, it will be the first representative of this family in the Iberian Peninsula. In the late Barremian site of Vallipón, high number of isolated lower and upper teeth of Eobaatar is found, together with other pinheirodontid and paulchoffatiid specimens. To date, the most complete Early Cretaceous multituberculate fossil record is present in the Iberian Peninsula, which ranges from the Berriasian to late Barremian assemblages. These Iberian Early Cretaceous multituberculate faunas comprise endemic Iberian Jurassic survivors (Paulchoffatiidae), those which are currently only recorded in Britain and in the Iberian Peninsula (Pinheirodontidae, Albionbaataridae, and possibly Plagiaulacidae), and others which are also registered in Asia (Eobaataridae). The presence of the eobaatarid Eobaatar from the Hauterivian/Barremian transition to late Barremian in the Iberian Peninsula, and during the Barremian in Britain and Aptian or Albian in Asia, suggest that geographical connections between these areas could have existed either sporadically or constantly for most of the Early Cretaceous. This hypothesis is supported by other palaeontological data such as the Gobiconodontidae mammals (Cuenca-Bescós and Canudo, 2003), some Sauropoda and Ornithopoda dinosaurs (Canudo et al ., 2002). Key words: multituberculates, Early Cretaceous, Iberian Peninsula, systematic, palaeobiogeography 16 .