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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”.

A new section including nine stratigraphically superposed microvertebrate fossil localities from the Calatayud-Montalbán basin (Spain) is presented. The Cañada localities and the small mammal assemblages are described, allowing a biostratigraphical correlation with the lower Vallesian from the nearby section of Nombrevilla. The results of this work are important because they help to improve the time resolution of the lower Vallesian faunal record from the Daroca area and to precise their relative biostratigraphical position. In addition, the upper part of the Cañada section includes two Turolian faunas, increasing the poor record from this age in the Calatayud-Montalbán basin.Se da a conocer una nueva sección que incluye nueve yacimientos de microvertebrados en superposición estratigráfica en la Cuenca de Calatayud-Montalbán (España). Se describen las localidades de la sección de la Cañada y sus faunas de micromamíferos, lo que posibilita su correlación con el Vallesiense inferior de la cercana sección de Nombrevilla. Los resultados obtenidos en este trabajo son importantes debido a que ayudan a mejorar la resolución temporal del registro faunístico del Vallesiense inferior del área de Daroca, y a precisar su posición bioestratigráfica relativa. Por otra parte, el tramo superior de la sección de la Cañada incluye dos faunas del Turoliense que incrementan el escaso conocimiento del registro de esta edad en la Cuenca de Calatayud-Montalbán.

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 paleontological sites of Toril 3A and B (Upper Aragonian, Biozone C3, MN 7/8) posses an exceptional and abundant fauna of vertebrates. From 1997 until 2001 these two localities have been object of systematic paleontological excavations. Up to now 36 species of large and small mammals have been found in these localities; the association of vertebrates also includes amphibians, reptiles and birds, among the remains of fossils birds it is frequent to found egg shell fragments. There are not significant differences in the qualitative and quantitative faunistic composition of the two sites; in both the undetermined bone fragments and the remains of chelonians, most of them dermal bones, are the dominant fossils. An important characteristic is the abundance of small size hornless ruminants, which are quite scarce in the stratified sites of the Spanish Aragonian. Neither there are differences in the composition of the micromammals, the association is overwhelmingly dominated (more than 95%) for different cricetid species; in Toril 3A beavers reappears for the first time during the Aragonian, and they will be frequent in younger faunas of the same basin. The fossils were deposited in different sedimentary environments, related with alluvial and shallow lacustrine environments.

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.

The Valles-Penedes Basin (Catalonia, Spain) is classical area for the study of Miocene land mammal faunas. Nevertheless, the early Miocene part of the record has deserved little attention as compared to younger intervals. Most notably, the small mammals of this age have not been described in detail, consequently hampering the correlation of the Valles-Penedes record with other chronological schemes. In this work we describe the rich and diverse small mammal fauna from Les Cases de la Valenciana site (Gelida, Alt Penedes) which includes marsupials, eulipotyphlans, lagomorphs and rodents. On the basis of the presence of the cricetids Megacricetodon and Democricetodon this site is correlated with European Neogene zone MN4, yielding an age of 17–16 Ma. However, the rodent assemblage is comparable to that of chronologically close localities of the Calatayud-Montalban Basin (Aragon, Spain), indicating that the same biochronological scheme can be applied to both areas. In this way, the coexistence of the eomyids Ligerimys ellipticus and Ligerimys florancei coupled with the presence of Megacricetodon primitivus indicates a correlation with local biozone Ca of the Calatayud-Montalban Basin, ranging from 16.3 to 16 Ma. Finally, the correlation of other early Miocene sites of the Valles-Penedes Basin is discussed and refined.

In the Iberian Peninsula, Miocene apes (Hominoidea) are generally rare and mostly restricted to the Valles-Penedes Basin. Here we report a new hominoid maxillary fragment with M2 from this basin. It was surface-collected in March 2017 from the site of Can Pallars i Llobateres (CPL, Sant Quirze del Valles), where fossil apes had not been previously recorded. The locality of provenance (CPL-M), which has delivered no further fossil remains, is located very close (ca. 50 m) to previously known CPL outcrops, and not very far (ca. 500 m in NW direction) from the classical hominoid-bearing locality of Can Poncic 1. Here we describe the new fossil and, based on the size and proportions of the M2, justify its taxonomic attribution to Hispanopithecus cf. laietanus, a species previously recorded from several Vallesian sites of the Valles-Penedes Basin. Based on the associated mammalian fauna from CPL, we also provide a biochronological dating and a paleoenvironmental reconstruction for the site. The associated fauna enables an unambiguous correlation to the Cricetulodon hartenbergeri – Progonomys hispanicus interval local subzone, with an estimated age of 9.98–9.73 Ma (late Vallesian, MN10). Therefore, CPL-M is roughly coeval with the Hispanopithecus laietanus-bearing localities of Can Llobateres 1 and Can Feu 1, and minimally older than those of La Tarumba 1 and Can Llobateres 2. In contrast, CPL-M is younger than the early Vallesian (MN9) localities of Can Poncic 1 (the type locality of Hispanopithecus crusafonti) as well as Polinya 2 (Gabarro) and Estacio Depuradora d’Aigues Residuals–Riu Ripoll 13, where Hispanopithecus sp. is recorded. The associated fauna from CPL indicates a densely forested and humid paleoenvironment with nearby freshwater. This supports the view that Hispanopithecus might have been restricted to dense wetland forests soon before its extinction during the late Vallesian, due to progressive climatic deterioration. Coupled with the existence of other fossiliferous outcrops in the area, this find is most promising for the prospect of discovering additional fossil hominoid remains in the future.