Aim: The Messinian salinity crisis (MSC) was an extraordinary geological event that affected the whole Mediterranean region as well as the global marine circulation between 5.97 and c. 5.33 Ma. One ...of its most direct effects was the emersion of land masses and the subsequent establishment of land bridges that led to common terrestrial faunal exchanges. However, the details of the onset of these exchanges have been a matter of controversy. New findings from southern Iberia of small mammal remains with African similarities have enabled us to review the Messinian faunal exchanges in the Mediterranean region. Location: Mediterranean region. Methods: Small mammal remains with African similarities from two new southern Iberian sites were studied. The small mammal associations of eight Miocene-Pliocene North African sites were also reviewed. Results: Two taxa with African similarities were identified at the Iberian study sites: Debruijnimys almenarensis and a Ruscinomys-like form (cf. Ruscinomys) with a strong spur in the lingual lobe of the anterocone in the M¹, a feature observed in North African Ruscinomys and eastern Mediterranean Byzantinia. The taxonomic status of some North African species and/or genera, such as Castillomys, Occitanomys and Prolagus, should be revised according to the new phylogenetic relationships established in European faunas. Main conclusions: Two hypotheses can be proposed for the origin of the African Ruscinomys: (1) among the Iberian Ruscinomys or (2) from the eastern Mediterranean Byzantinia. Our data, currently from only a few, albeit significant, taxa, tend to support an Iberian origin. The discussion presented in this paper suggests an age near the closure of the last Betic Gateway (c. 6.18 Ma) for the first small mammal exchange between Africa and Europe, as well as a single migratory wave of small mammals, filtered by their ecological preferences from this point until the end of the MSC.
The gerbillid Myocricetodon is mainly known from the Miocene of Africa and Asia, but some small samples of this genus have been identified in southwestern Europe, interpreted as immigrants driven by ...the Messinian Salinity Crisis. However, the specific determination of these European populations and their relationships with African forms have proved controversial. The population from Negratín-1 (Guadix Basin, southern Spain) was attributed to the African species Myocricetodon jaegeri, but other European samples have still not been determined at the specific level. Here we describe the material of Myocricetodon from Almenara-M (eastern Spain), which represents the most abundant sample of the genus known from Europe, confirming its assignation to M. jaegeri. We also analyze material from Salobreña, Pino Mojón (southern Spain) and Castelnou-3 (southern France), concluding that these samples belong to the same species. The presence of these coeval and conspecific populations of Myocricetodon is explained by a single migratory event from northern Africa. The occurrence of Myocricetodon, interpreted as an indicator of warm and arid conditions, is restricted to southern and eastern Spain and the southeastermost extreme of France, being mainly limited to the Mediterranean coast. It is absent in other Iberian areas, such as the Granada, Cabriel and Teruel basins, despite their rich and well-studied record of late Miocene mammals. This distribution suggests the existence of different environmental (more humid) conditions in those areas during the latest Miocene, as already proposed for the Granada Basin. Our data also indicate that the presence of Myocricetodon in Europe was limited to a short interval close to the Miocene-Pliocene boundary, contrarily to other gerbils, namely Debruijnimys, which persisted during the Pliocene. This suggests that Myocricetodon could be extremely sensitive to environmental factors and its occurrence in Europe was linked to a specific moment of arid conditions.
•All the European samples of the African gerbil genus Myocricetodon are described•These populations from Spain and SE France are assigned to the species M. jaegeri.•This rodent was limited to the Mediterranean coast, being absent in inner basins.•The presence of Myocricetodon in Europe is restricted to the latest Miocene.•Myocricetodon was linked to particularly arid environmental conditions.
The new species Agerinia smithorum (Adapiformes, Primates) from the early Eocene of the Iberian Peninsula is erected in this work. An emended diagnosis of the genus is provided, together with a broad ...description of the new species and comparisons with other samples assigned to Agerinia and other similar medium‐sized cercamoniines. The new species is based on the most complete specimen of this genus published to date, a mandible preserving the alveoli of the canine and P1, the roots of the P2 and all teeth from P3 to M3. It was found in Casa Retjo‐1, a new early Eocene locality from Northeastern Spain. The studied specimen is clearly distinguishable from other cercamoniines such as Periconodon, Darwinius, and Donrussellia, but very similar to Agerinia roselli, especially in the similar height of P3 and P4 and the general morphology of the molars, therefore allowing the allocation to the same genus. However, it is undoubtedly distinct from A. roselli, having a less molarized P4 and showing a larger paraconid in the M1 and a tiny one in the M2, among other differences. The body mass of A. smithorum has also been estimated, ranging from 652 to 724 g, similar to that of A. roselli. The primitive traits shown by A. smithorum (moderately molarized P4, large paraconid in the M1 and small but distinct in the M2) suggest that it could be the ancestor of A. roselli.
Recent study of the small mammals (rodents and insectivores) from several fossil-bearing sites situated in the central sector of the Guadix Basin (Southern Spain) has notably increased the knowledge ...of the mammal assemblages that existed in Southern Iberia from the latest Miocene to the earliest Pleistocene. On the basis of this new information, we propose a biozonation for the continental deposits of the Guadix Basin, which consists of six biozones ranging in age from the late Turolian (MN13) to the early Villanyian (MN17). These biozones, defined according to the rules of the International Stratigraphical Guide, include not only the mentioned recently discovered fossil sites, but also other, previously known, localities of the basin. Finally, we integrate the described biozones in the Neogene Mammal units and the European Land Mammal Ages, correlate them with several classical mammal sites from other Iberian basins and the rest of Europe, and establish an approximate numerical age for the lower and upper limits of each biozone.
The Late Miocene and Pliocene continental sediments in the Granada Basin (southern Spain) have yielded large amounts of fossil small mammals in 37 localities from 11 sections. The aim of this paper ...is to integrate faunistic, stratigraphic, and sedimentary criteria to unravel the geological history of the continental infilling of the basin.
The palaeontological study has led to a detailed biozonation on the basis of rodents, which helps to correlate in detail the different sedimentary units found in the basin, and to follow the changes of the different sedimentary systems and their palaeogeographical evolution through time.
Combination of the proposed biostratigraphy and the reinterpretation of the magnetostratigraphic analyses of the Barranco del Purcal section allows us to assign an absolute age slightly older than 5.23 Ma to the Turolian–Ruscinian boundary (MN13‐MN14).
: This paper reports the first record of Desmanella (Mammalia, Soricomorpha) from the Granada Basin in southern Iberian Peninsula, which represents its south‐westernmost occurrence in all Eurasia. ...It is a controversial taxon whose systematic assignment has been discussed for a long time. This genus belongs to the family Talpidae, a group of insectivores that include extant moles, shrew moles and desmans. Desmanella was very abundant in the late Miocene and early Pliocene of Eurasia, including several basins of northern Iberian Peninsula, but it has not been found until now in southern Iberia. Previous studies have shown that the faunal record and the climatic conditions during the Neogene in the Granada Basin were different from other areas of the Iberian Peninsula. The particular distribution of Desmanella supports the hypothesis that specific climatic features (wetter than neighbouring areas) prevailed in the Granada Basin during the late Turolian (late Miocene).
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