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Over the last half a century, a massive amount of data has been gathered on Neogene rodents of Europe. Using the NOW database, we analysed changes in generic diversity during the Neogene and the beginning of the Quaternary. Studies as the present are useful for exploring major changes in diversity, but the pitfalls are many and varied. Whereas the quality of the fossil record is good, there are notable exceptions. Within our dataset, MN 1, MN 12 and MN 17 stand out for the limited number of localities available and the record of the eastern Mediterranean is clearly as yet poorer than that from central Europe and the Iberian Peninsula. The record can be influenced by incomplete faunal lists, outdated literature and unresolved taxonomies. In addition, the use of the MN system presumably obscures patterns, as it often does not allow for a co-eval comparison between various regions. Reconstruction of major patterns starts with the understanding of basic data. Despite all these limitations the results of this work indicate that the record for central Europe consistently shows higher diversity than lower latitudes. The highest peak in diversity is found in MN 15, but the record of the Iberian Peninsula shows no increase at that time. The rodent diversity is surprisingly constant during most part of the Neogene, the stronger variations being related to the diversification of the murinae and arvicolinae groups and decline of the cricetine. © 2020 Sciendo. All rights reserved.

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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.

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.

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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.

El sector occidental de la Cuenca de Madrid está constituido por depósitos siliciclásticos, en general areniscas arcósicas y lutitas, fundamentalmente de edad neógena. A partir de la cartografía y del estudio estratigráfico detallado de los materiales terciarios presentes en varias hojas geológicas a escala 1:50.000 de la zona SO de la cuenca, se han reconocido cinco unidades estratigráficas cuya denominación alude a las áreas donde aparecen mejor representadas. De base a techo, son: 1) Unidad de arcosas y lutitas de El Carpio, 2) Unidad de arcosas con cantos y conglomerados del Embalse de Castrejón, 3) Unidad de arcosas y lutitas de Los Vergales, 4) Unidad de arcosas gruesas con cantos de Batres, y 5) Unidad de arcosas blancas de Carranque-Griñón. Los límites entre ellas quedan definidos por cambios en la evolución en la vertical de los depósitos siliciclásticos, sobre todo relativos a su granulometría. Los materiales reconocibles en cada una de estas unidades se depositaron en su mayor parte en sistemas de abanicos aluviales, con variaciones en el carácter permanente o efímero de los sistemas distributarios y, en menor medida, en ambientes lacustres someros y palustres. La edad del conjunto estratigráfico analizado abarca esencialmente el Mioceno inferior y medio, no descartándose que la base de la Unidad de arcosas y lutitas de El Carpio sea Paleógeno y que la parte superior de la Unidad de arcosas blancas de Carranque-Griñón alcance el Mioceno superior (Vallesiense).

The Cerro de los Batallones (Los Batallones Butte) is located in the central-northern area of the Madrid Basin, central Spain. Six vertebrate localities containing a large variety of mammals together with amphibians, fishes and plant remains 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), palaeosols formed of sepiolite and opal (Unit II), and siliclclastic, marlstone and carbonate beds (Unit III). Both the patch-like geometry and the composition of the deposits bearing the Upper Vallesian fauna indicate that their accumulation took place in cavities which acted as traps for both carnivores and herbivores. Although there is not conclusive evidence for the precise mechanism of formation of the holes, a combined effect of vertisol development followed by subsurface erosion processes ("pseudokarst") can be suggested as most reliable. Moreover, formation of the vertebrate localities of Cerro de los Batallones could provide some clues on the geological evolution of the Madrid Basin during the Upper Miocene

The Cerro de los Batallones (Los Batallones Butte) is located in the central-northern area of the Madrid Basin, central Spain. Six vertebrate localities containing a large variety of mammals together with amphibians, fishes and plant remains 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), palaeosols formed of sepiolite and opal (Unit II), and siliclclastic, marlstone and carbonate beds (Unit III). Both the patch-like geometry and the composition of the deposits bearing the Upper Vallesian fauna indicate that their accumulation took place in cavities which acted as traps for both carnivores and herbivores. Although there is not conclusive evidence for the precise mechanism of formation of the holes, a combined effect of vertisol development followed by subsurface erosion processes ("pseudokarst") can be suggested as most reliable. Moreover, formation of the vertebrate localities of Cerro de los Batallones could provide some clues on the geological evolution of the Madrid Basin during the Upper Miocene

Six Upper Vallesian (Upper Miocene) fossil vertebrate sites have been found in the Cerro de los Batallones (Torrejón de Velasco, Madrid). These localities contain an exceptionally rich, varied and well-preserved vertebrate fauna. Carnivore species are strikingly well represented at Batallones 1 and 3, and large herbivore species, such as mastodons, rhinoceros and giraffes, are common in Batallones 2, 4 and 5. The mammalian association, together with the morphological features shown by the sedimentary fills of the mammal sites, enables 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. These new sites also will contribute to a better knowledge of some of the most scarce mammal groups in the Miocene fossil record

[EN] The Nombrevilla section in the Calatayud-Daroca basin (Central Spain) bears one of the best late Aragonian to early Vallesian large and small vertebrate fossil records in Europe, including important findings of the equid Hipparion. Magnetostratigraphic dating of the Nombrevilla section thus provides further age constraints on the timing of Hipparion dispersal in Europe, a bioevent which defines the base of the Vallesian mammal stage. Correlation of the Nombrevilla magnetic polarity stratigraphy to the geomagnetic polarity time scale is supported by the identification of the characteristic long normal chron C5n in the upper half of the section, in association with early Vallesian (early late Miocene) fossils. The classic mammal fossil site Nombrevilla 1, recording the earliest occurrence of Hipparion, correlates to the lower third of chron C5n, and yields an interpolated age of about 10.7-10.8 Ma. This age is in agreement with magnetostratigraphic dating of earliest occurrences in Siwaliks of Pakistan and some 40Ar/39Ar ages of Mediterranean sites. The youngest pre-Hipparion large mammal fossil record corresponds to Nombrevilla 9, a site wich approximately correlates to chron C5r.1n, at about 11.1 Ma. This result is nearly in conflict with the data from the Vallès-Penedès, where a Hipparion bearing site is correlated to the same chron. In addition, Nombrevilla 9 yields a small mammal assemblage which corresponds to local zone H, a biozone wich was classically correlated to the lower Vallesian. This implies a diachrony of about 300 kyr between the lower boundary of zone H and the first occurrence of Hipparion (base of the Vallesian) in the Calatayud-Daroca basin. Correlation of the Aragonian levels of Nombrevilla 2, 3 and 4 is not yet certain and would require further downward extension of the magnetostratigraphy in a neighbouring section. Nevertheless, we can confidently say these localities are younger than 11.6 Ma., [ES] La sucesión estratigráfica de Nombrevilla en la cuenca de Calatayud-Daroca (Cordillera Ibérica) contiene uno de los más ricos registros de macro y microvertebrados fósiles del tránsito Aragoniense/Vallesiense. El estudio magnetoestratigráfico de Nombrevilla aporta nuevos datos sobre la cronología de la aparición de Hipparion, un bioevento que define la base del piso Vallesiense. La correlación con la escala de tiempo de polaridad geomagnética está basada en la identificación de C5n, un cron de más de 1 Myr de polaridad normal que es característico del Mioceno superior. La localidad clásica Nombrevilla 1, que representa el registro más antiguo de Hipparion, se correlaciona con el tercio inferior del cron C5n, y le corresponde una edad interpolada de 10.7-10.8 Ma. Este dato se corresponde muy bien con la datación magnetoestratigráfica del mismo bioevento en Siwaliks (Pakistán) así como las dataciones radiométricas 40Ar/39Ar en otras localidades de la región mediterránea. La localidad con macrovertebrados más alta sin Hipparion en la serie de Nombrevilla es Nombrevilla 9, que se correlaciona aproximadamente con el cron C5r.1n (11.1 Ma). Este resultado no se corresponde exactamente con los resultados del Vallès-Penedès, donde una edad muy similar se obtiene para la primera aparición de Hipparion. Aparte, Nombrevilla 9 es particularmente significativa puesto que muestra una asociación de microvertebrados correspondiente a la zona local H, que clásicamente se había identificado con el Vallesiense inferior. Los nuevos datos señalan una diacronía de cerca de 300 kyr. entre el limite inferior de la zona H y la aparición de Hipparion en Calatayud-Daroca. La correlación de las localidades del Aragoniense superior Nombrevilla 2, 3 y4 es relativamente incierta, si bien es seguro que se encuentran en la parte superior del cron C5r, con una edad no menor que 11.6 Ma., This research was partially supported by CICYT grants PB97- 0882-C03-01; PB98-0691-01 and PB98-0691-02, and by the Dutch research centre for Integrated Solid Earth Sciences (ISES).

Six Upper Vallesian (Upper Miocene) fossil vertebrate sites have been found in the Cerro de los Batallones (Torrejón de Velasco, Madrid). These localities contain an exceptionally rich, varied and well-preserved vertebrate fauna. Carnivore species are strikingly well represented at Batallones 1 and 3, and large herbivore species, such as mastodons, rhinoceros and giraffes, are common in Batallones 2, 4 and 5. The mammalian association, together with the morphological features shown by the sedimentary fills of the mammal sites, enables 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. These new sites also will contribute to a better knowledge of some of the most scarce mammal groups in the Miocene fossil record

Las cuencas de Calatayud-Daroca y Teruel contienen un registro sedimentario y faunístico muy completo del Neógeno continental español. En ellas están definidas las, secciones tipo del Rambliense, Aragoniense, Turoliense y Alfambriense. A su vez, el Vallesiense se encuentra muy bien representado en la parte norte de la Cuenca de Teruel, tanto litoestratigráficamente como por la amplia sucesión de faunas de vertebrados que contiene. En este trabajo se presenta un resumen y puesta al día de la información estratigráfica y sedimentológica disponible sobre las formaciones neógenas de ambas cuencas, incluyendo además datos recientes sobre el límite Aragoniense-Vallesiense en el área de Daroca-Nombrevilla y sobre el registro sedimentario de edad Plioceno en la parte más septentrional de la región de Teruel-Alfambra. Se presenta asimismo un cuadro sintético de las columnas magnetoestratigráficas elaboradas en los últimos años. Con carácter preliminar, se muestran las curvas de evolución paleoclimática (humedad/temperatura) deducibles de las asociaciones de micromamíferos presentes en una densa sucesión de yacimientos que abarcan todo el Mioceno. Las diferencias en los resultados obtenidos sobre la evolución paleoclimática de ambas cuencas son posiblemente debidas a la distinta metodología utilizada en el análisis de las asociaciones faunísticas. Por otra parte, se discuten las faltas de ajuste detectadas, al menos para algunos intervalos temporales, entre los resultados deducibles de este tipo de interpretación paleoclimática y los que se derivan del análisis sedimentológico de los depósitos. The Calatayud-Daroca and Teruel basins (NE Spain) show a very complete sedimentary and faunal record of the Spanish continental Neogene. The stratotypes for the Ramblian, Aragonian, Turolian and Alfambrian stages have been defined in these basins. Moreover, the Vallesian is well recorded especially in the northern Teruel Basin. This paper gives a state-of-the-art summary of the available information generated in the latest years by detailed sedimentological, biostratigraphical and magnetostratigraphical studies of the Neogene deposits of the basins. Recent results concerning the Aragonian-Vallesian boundary in the Daroca-Nombrevilla area are presented. A general integrated scheme of the magnetostratigraphic logs obtained from a large number of stratigraphic sections throughout the region is also included. Preliminary palaeoclimatic evolutionary curves (humidity/ temperature) are proposed for the Miocene stratigraphic record of the basins. The curves have been inferred from detailed analysis of the micromammal associations found in an extremely dense succession of mammal localities. Differences in the palaeoclimatic curves proposed for Calatayud-Daroca and Teruel may be explained by the use of different methodologies. Discrepancies between sedimentological and faunal based interpretations of the palaeoclimatic evolution of some intervals of the Miocene are discussed.