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Altres ajuts: CERCA Programme/Generalitat de Catalunya. Les tasques de camp es van poder dur a terme gràcies al suport del Departament de Cultura de la Generalitat de Catalunya (projecte 2014/100584) i la National Geographic Society (beca d'exploració ref. 9640-15). Les intervencions paleontològiques recents han mostrat que el registre de vertebrats continentals del Miocè inferior de la conca del Vallès-Penedès és molt més ric i continu del que es pensava. Avui dia es coneixen una vintena de jaciments que han lliurat tant microvertebrats com macrovertebrats. Els nostres estudis biostratigràfics han permès una datació precisa dels diferents jaciments i també dels principals esdeveniments faunístics i climàtics.

The Vallès-Penedès Basin (Catalonia, Spain) is a classical area for the study of the Miocene land mammal faunas and includes one of the densest and most continuous records in Eurasia. Furthermore, it is the type area for the Vallesian European land mammal age. After decades of study a huge amount of bio-and magnetostratigraphic data have been collected, allowing an unprecedented dating accuracy. Here we provide an updated local biostratigraphy for the late Aragonian, Vallesian and Turolian of the Vallès-Penedès Basin. This new biostratigraphic scheme is almost exclusively based on fossil rodents, which are the most abundant and one of the best known mammal orders in the area. Our proposal represents a significant refinement compared to previous attempts and provides a formal diagnosis and description of each zone, as well as clear definition of boundaries and a reference locality and section. The chronology of zone boundaries and main bioevents is based on detailed magnetostratigraphic data. The defined biozones allow for the correlation of the sites without associated magnetostratigraphical data. Finally, the correlation of the Vallès-Penedès local zones with other detailed local biostratigraphies, such as those of the Calatayud-Montalbán and Teruel basins (east-central Spain) is discussed. The sequence and chronology of the main bioevents is roughly comparable, although the rodent succession and the structure of the assemblage show important differences between these areas.

This paper contains formal definitions of the Early to Middle Aragonian (Late Early–Middle Miocene) smallmammal biozones from the Aragonian type area in North Central Spain. The stratigraphical schemes of two of the best studied areas for the Lower and Middle Miocene, the Aragonian type area in Spain and the Upper Freshwater Molasse from the North Alpine Foreland Basin in Switzerland, have been compared. This comparison allows the analysis of the order of shared mammal events in the two countries, and the quantification of the resulting asynchronies based on their temporal correlations. The order of the events is very similar in Spain and Switzerland. In order to estimate the diachrony, two age-model options are used for the Swiss record. Our preferred option yields no discrepancies with SW European paleomagnetic and radiometric calibrations of the Ramblian and Early Aragonian bioevents. All Swiss first taxa occurrences precede those in the Aragonian type area by 0.74Myr on average. The asynchronies (1-2Myr) of the species arriving in the Late Middle to Early Late Aragonian may be higher than in the Early Aragonian (0-1Myr). The implications for the biochronological mammal Neogene system are discussed. Evidence is given confirming the unfeasibility of a formal European biozonation, since it is realised, that 1) most indicator species and many genera of rodents yielding the most detailed zonations have limited geographical ranges hampering recognition of the mammal Neogene zones; and 2) first and last taxon occurrences are diachronical. Therefore, the mammal Neogene system based on a sequence of time-ordered reference localities is preferred to the one based on selected bioevents “developed in widespread geographic areas”.

The Cerro de los Batallones (Los Batallones Butte) is located in the central-northern area of the Madrid Basin, central Spain. Nine vertebrates localities containing a large variety of mammals of Upper Vallesian Age (Late Miocene) have been found associated with the sediments forming the butte. From bottom to top, these sediments consist of magnesian lutite beds (Unit I), paleosols formed of sepiolite and opal (Unit II), and siliclastic, marlstone and carbonate beds (Unit III). The set of ERT profiles developed in Los Batallones Butte have demonstrate that electrical imaging techniques are an estimable tool for the characterization and prospecting of fossil sites developed in fine-grained siliciclastic sequences. These localities contain an exceptionally rich, varied and well-preserved vertebrate fauna together with invertebrate and plant fossils. Carnivore species are strikingly well represented at Batallones 1 and 3, and large herbivore species, such as mastodons, rhinoceros and giraffes, at Batallones 2, 4, 5 and 10. The taphonomical studies, together with the morphological features shown by the sedimentary fills of the mammal localities, permit an overall interpretation of these deposits as vertebrate traps. The study of these localities should offer a significant contribution to our understanding of the formation pattern of trap-like paleontological sites - which so far have been typically reported in karstic-type systems -, as well as an important source of paleobiological information about numerous vertebrate groups.

Una nueva fauna de vertebrados del Aragoniense medio (Mioceno medio) del área urbana de Madrid es presentada. Se incluye una descripción del contexto estratigráfico del yacimiento y las excavaciones que se han realizado en esta localidad fosilífera. Los estudios preliminares han permitido realizar las determinaciones taxonómicas incluidas en el trabajo. El estado evolutivo de algunos de los taxa registrados en esta localidad ha permitido su correlación con la Biozona Dc del Aragoniense medio., A new vertebrate fauna from the Middle Aragonian (Middle Miocene) of the city of Madrid is presented. A description of the stratigraphic framework and the field campaigns carried out on this fossiliferous locality are included. The preliminary studies have allow the taxonomic assignations included on this work. The evolutionary stage of several taxa recorded in the locality allowed its correlation to the Middle Aragonian Biozone Dc.

The Vallès-Penedès Basin (Catalonia, Spain) is a classical area for the study of the Miocene land mammal faunas and includes one of the densest and most continuous records in Eurasia. Furthermore, it is the type area for the Vallesian European land mammal age. After decades of study a huge amount of bio- and magnetostratigraphic data have been collected, allowing an unprecedented dating accuracy. Here we provide an updated local biostratigraphy for the late Aragonian, Vallesian and Turolian of the Vallès-Penedès Basin. This new biostratigraphic scheme is almost exclusively based on fossil rodents, which are the most abundant and one of the best known mammal orders in the area. Our proposal represents a significant refinement compared to previous attempts and provides a formal diagnosis and description of each zone, as well as clear definition of boundaries and a reference locality and section. The chronology of zone boundaries and main bioevents is based on detailed magnetostratigraphic data. The defined biozones allow for the correlation of the sites without associated magnetostratigraphical data. Finally, the correlation of the Vallès-Penedès local zones with other detailed local biostratigraphies, such as those of the Calatayud-Montalbán and Teruel basins (east-central Spain) is discussed. The sequence and chronology of the main bioevents is roughly comparable, although the rodent succession and the structure of the assemblage show important differences between these areas.