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Altres ajuts: CERCA Programme/Generalitat de Catalunya, Els Casots is one of the richest fossil vertebrate sites of the Vallès-Penedès Basin (Catalonia, Spain). It was discovered in 1989 and excavated briefly during the 1990s, resulting in the recovery of thousands of remains and the erection of several new mammal species. Excavations were resumed in 2018 and continue to date. Here we provide updated results regarding the age, stratigraphy, biota and palaeoenvironment of the site. The age of the site is well constrained to ~15.9 Ma thanks to recent bio- and magnetostratigraphic data, thus coinciding with the Miocene Climatic Optimum (MCO). The stratigraphic succession at the site area indicates lacustrine to palustrine environments with cyclically oscillating water level. There are several fossiliferous layers that have yielded a vertebrate fauna comprising up to 75 different vertebrate species including amphibians, reptiles, birds and mostly mammals. The finding of several articulated partial skeletons indicate that the site records an autochthonous to parautochthonous assemblage. The abundance and completeness of the vertebrate remains together with a well-constrained age and detailed stratigraphic and palaeoenvironmental data, make els Casots a key site for understanding wetland ecosystems in southern Europe during the MCO.

Els Casots is one of the richest fossil vertebrate sites of the Vallès-Penedès Basin (Catalonia, Spain). It was discovered in 1989 and excavated briefly during the 1990s, resulting in the recovery of thousands of remains and the erection of several new mammal species. Excavations were resumed in 2018 and continue to date. Here we provide updated results regarding the age, stratigraphy, biota and palaeoenvironment of the site. The age of the site is well constrained to ~15.9 Ma thanks to recent bio- and magnetostratigraphic data, thus coinciding with the Miocene Climatic Optimum (MCO). The stratigraphic succession at the site area indicates lacustrine to palustrine environments with cyclically oscillating water level. There are several fossiliferous layers that have yielded a vertebrate fauna comprising up to 75 different vertebrate species including amphibians, reptiles, birds and mostly mammals. The finding of several articulated partial skeletons indicate that the site records an autochthonous to parautochthonous assemblage. The abundance and completeness of the vertebrate remains together with a well-constrained age and detailed stratigraphic and palaeoenvironmental data, make els Casots a key site for understanding wetland ecosystems in southern Europe during the MCO.

[Abstract] Pliocene occurrences of Prolagus Pomel, 1853 in central Europe represent anomalies out of the peri-Mediterranean area, at that time the core distribution of the genus. Though known for several decades, those materials never underwent a general revision. The detailed analysis and comparison of all available materials performed here revealed two phenotypic entities: 1) Prolagus bilobus Heller, 1936 (Gundersheim localities, Raciszyn 1), for which were defined additional diagnostic characters and ontogenetic patterns of variation (d3/p3 and mandible); and 2) Prolagus sp. (Beremend 26/39), probably a new species. All the available occurrences are dated to MN15b. The morphological trends towards the reduction of p3 entoconid and of enamel folding evidenced in Pliocene Prolagus of western Europe cannot be recognized in coeval central European forms. Evidently, P. bilobus and Prolagus sp. do not pertain to the western European clade, whose separation is known since the early late Miocene. We hypothesize that at least P. bilobus originated from a dispersal of Prolagus from south-eastern regions of Europe rather than from an autochthonous speciation of isolated populations left as a relict after the southward displacement of Prolagus distribution area. The dispersal is likely to be related to the Pliocene global environmental changes during which extensive faunal rearrangements took place in Europe, in particular to those near the early/late Pliocene boundary., [Résumé] Prolagus Pomel, 1853 (Lagomorpha, Mammalia) dans le cadre des réarrangements fauniques du Pliocène de l’Europe centrale. Le peu de données dont nous disposons sur le Prolagus Pomel, 1853 du Pliocène d’Europe centrale représentent des anomalies dans la distribution géographique du genre, qui, à cette époque, est limité à la zone péri-Méditerranéenne. Bien que la présence de Prolagus dans le Pliocène d’Europe centrale est connue depuis plusieurs décennies, de tels matériels n’ont jamais fait l’objet d’une révision générale. Une analyse détaillée et une comparaison de tous les matériels disponibles étudiés ici ont permis d’identifier deux éntités phénotypiques : 1) Prolagus bilobus Heller, 1936 à Gundersheim (plusieurs localités) et Raciszyn 1, pour lequel des caractères diagnostiques additionnels et des modèles ontogénétiques de variation (d3/p3 et mandibule) ont été définis ; et 2) Prolagus sp. à Beremend 26/39, qui représente probablement une nouvelle espèce. Toutes les occurrences disponibles sont datées du MN15b. Les tendances morphologiques vers une réduction de l’entoconide de p3 et une diminution du repli de l’émail, mises en évidence dans les espèces pliocènes de Prolagus d’Europe occidentale, n’ont pas été reconnues dans des formes contemporaines d’Europe centrale. Prolagus bilobus et Prolagus sp. n’appartiennent manifestement pas au clade ouest-européen, dont la séparation est connue depuis le début du Miocène supérieur. Notre hypothèse est qu’au moins P. bilobus trouve son origine dans une dispersion des populations à partir de l’Europe sud-orientale plutôt que, comme on le croyait autrefois, dans une spéciation autochtone de populations isolées, laissées telles des vestiges à la suite du déplacement vers le sud de l’aire de distribution géographique de Prolagus. Cette dispersion est probablement liée aux changements environnementaux à l’échelle globale survenus au Pliocène, et responsables de changements environnementaux globaux pendant lesquels d

[Abstract] Revisions performed in the last 15 years added remarkable novelties to the taxonomy and biochronology of Italian fossil lagomorphs. Several new taxa have been erected basing on new materials and on the revision of old materials. This paper aims to illustrate the state of the art of such researches. The lagomorph diversity in the Italian Neogene and Pleistocene is quite high, accounting 9 ochotonids, 14 leporids, and 3 stem lagomorphs. Among the lagomorph taxa recorded in Italy, quite a high number are insular or continental endemics. The oldest Italian lagomorphs are the insular endemic Paludotona aff. minor, P. etruria and P. minor from the early-middle Turolian of the Tusco-Sardinia palaeobioprovince, and Prolagus apricenicus and P. imperialis from the late Turolian of the Abruzzi-Apulia palaeobioprovince. In the Italian peninsula, lagomorphs are known since the late Turolian (early Messinian). Prolagus appears in pre-evaporitic Messinian (Prolagus sorbinii) and gives rise to species endemic to the Italian peninsula (Prolagus italicus, late Villányian, central Italy; P. savagei/P. aff. sorbinii, early Villányian-early Biharian, NW and central Italy). The presence of Prolagus was probably constant until the early Biharian, age of its latest report in the Italian peninsula. The gap in the Pliocene fossil record is apparent and due to the extreme scarcity of fossil localities bearing continental vertebrates in the Italian Pliocene. The Asian genus Ochotona appeared at least twice in the Middle-Late Pleistocene of NE Italy, in correspondence of cold climatic phases. Prolagus of the latest Miocene-Early Pliocene of Italy represents the stock which originated the Sardinian lineage of Prolagus. The Sardinian species of Prolagus form an endemic insular anagenetic lineage whose oldest element is the earliest Late Pliocene P. aff. figaro, and which persists till historical times. The main turnover in the lineage, i.e. the transition P. figaro-P. sardus, is an eve