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The upper Eocene-Oligocene carnivorous mammals from the Quercy Phosphorites (France) housed in Belgian collections
Abstract and Figures
The Quercy Phosphorites Formation in France is world famous for its Eocene to Miocene faunas, especially those from the upper Eocene to lower Oligocene, the richest of all. The latter particularly helped to understand the ‘Grande Coupure’, a dramatic faunal turnover event that occurred in Europe during the Eocene-Oligocene transition. Fossils from the Quercy Phosphorites were excavated from the middle 19th century until the early 20th century in a series of sites and became subsequently dispersed over several research institutions, while often losing the temporal and geographical information in the process. In this contribution, we provide an overview and reassess the taxonomy of these barely known collections housed in three Belgian institutions: the Université de Liège, KU Leuven, and the Royal Belgian Institute of Natural Sciences. We focus our efforts on the carnivorous mammals (Hyaenodonta and Carnivoramorpha) and assess the stratigraphic intervals covered by each collection. These fossils are derived from upper Eocene (Priabonian), lower Oligocene (Rupelian), and upper Oligocene (Chattian) deposits in the Quercy area. The richness of the three collections (e.g., the presence of numerous postcranial elements in the Liège collection), the presence of types and figured specimens in the Leuven collection, and some identified localities in the RBINS collection make these collections of great interest for further studies on systematics and the evolution of mammals around the ‘Grande Coupure’.
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... Les spéléothèmes sont de bonnes archives pour la datation des karsts actifs mais ne peuvent pas être utilisés pour dater les ciments calcitiques âgés de plus 600 000 ans ( Fig. 1.12) (Andersen et al., 2004 ;Cheng et al., 2013 ;Jaubert et al., 2016). Les paléokarsts sont scellés par des remplissages argileux et sableux qui peuvent contenir des fossiles datables Sigé et al., 1997 ;Solé et al., 2021). Néanmoins, cela dépend de leurs qualités, de leurs préservations et de leurs abondances. ...
... Néanmoins, ces cavités karstiques se forment antérieurement aux remplissages. Le début du colmatage des cavités karstiques se produit à partir de l'Éocène inférieur (Marandat et al., 1993 ;Laudet et al., 1997 ;Maitre et al., 2008 ;Escarguel et al., 2008 ;Maitre, 2014 ;Solé et al., 2021) au moment où elles sont connectées à la surface et aux formations sidérolithiques (Simon-Coinçon et al., 1992). La remontée du niveau de base dès la fin de l'Éocène provoque l'ennoiement de ces cavités et permet leur colmatage complet par des dépôts argileux rougeâtres, riches en nodules phosphatés et pisolithes de fer, qui sont à l'origine des phosphorites du Quercy Legendre et al., 1997). ...
... Par exemple, près de 12000 spécimens sont référencés dans le seul gisement du Pech du Fraysse (Legendre et al., 1997). Les faunes couvrent une période qui s'étend de l'Éocène inférieur au Miocène inférieur ( Fig. 2.38 et 2.39) (Rémy et al., 1987 ;Sigé et al., 1991 ;Marandat et al., 1993 ;Laudet et al., 1997 ;Maitre et al., 2008 ;Escarguel et al., 2008 ;Maitre, 2014 ;Solé et al., 2021) avec une résolution biochronologique élevée sur la période Bartonien-Chattien ( Fig. 2.38 et 2.39) (Rémy et al., 1987 ;Astruc et al., 2003). Legendre et Marandat, 1986 ;Hartenberger, 1987 ;Escarguel et al., 2008). ...
Dans un contexte de changement climatique et de pression croissante sur la ressource en eau des aquifères carbonatés, une meilleure compréhension du fonctionnement et de la recharge des réservoirs est nécessaire afin d'optimiser leur exploitation. Une caractérisation sédimentaire et diagénétique des calcaires s'avère indispensable. Ce travail pluridisciplinaire se concentre sur les roches carbonatées du Jurassique moyen et de l'Oxfordien de la bordure nord-est du Bassin Aquitain. Le premier objectif est de quantifier l'influence couplée des fluctuations climatiques à long terme et de la création d'accommodation sur les producteurs carbonatés et l'accumulation de carbonates. Le second objectif est de reconstruire l'histoire diagénétique et paléohydrologique du bassin et de proposer une méthode pour dater les phases de dissolution et les périodes de création de porosité dans les calcaires. Les études menées dans le Bassin Aquitain et l'ouest de la France montrent que l'augmentation du taux de création d'accommodation provoque (1) l'augmentation du taux d'accumulation de carbonates et (2) des changements de producteurs carbonatés, quel que soit le climat. En période de climat aride, la création d'espace disponible est comblée par une production micritique-microbienne. En climat humide, les taux d'accumulation de carbonate diminuent drastiquement et provoque le déclin des producteurs oolithiques, photozoan et micrite-microbien. La combinaison d'observation pétrographique et de la méthode géochronologique U-Pb permet de dater les phases de dissolution et de création de pores, mais également d'établir une paragenèse à grande échelle. Les processus de néomorphisme et dolomitisation sont datés au cours de la période Jurassique supérieur à Crétacé inférieur. Les processus de dissolution postérieure affectent préférentiellement les corps dolomitiques bajociens. Les âges U-Pb mettent en évidences une succession de phases de dissolution-recristallisation au Paléocène-Éocène. Les phases de cimentation calcitique sont synchrones des processus de dissolution lors de périodes de karstification et peuvent se produire en profondeur formant et comblant des pores vacuolaires de taille millimétriques à métriques.
... After more than 200 years of collecting around the world, some collections are now forgotten, lost, or understudied. In Europe, recently, several institutions are trying to highlight the most significant paleontological collection of mammals (e.g., Carrillo-Briceño et al., 2016;Solé et al., 2020;Van der Hoek, 2021;Vera et al., 2015;Zurita-Altamirano et al., 2019), a primacy for paleontological community. An example is the significant collection of Pleistocene megafauna from South America assembled by Santiago Roth. ...
Unlabelled:
The present work concerns xenarthrans from the collection of Santiago (Kaspar Jakob) Roth (1850-1924) housed at the Palaeontological Institute and Museum of the University of Zurich, one of the most important collections of Pleistocene mammals from Argentina in Europe. Roth was a paleontologist originally from Switzerland who prospected and collected a large amount of Pleistocene megafauna of the Pampean Region of Argentina. The xenarthrans are the main representatives of this collection in Zurich, with 150 specimens. Since 1920, this material has not been revised and is under studied. The present investigation corresponds to a taxonomic revision resulting in 114 reassignments, leading to document xenarthran diversity and discuss their paleoecologies. The high diversity reflects the paleoecology of the Pampean Region during the Pleistocene, with the various abiotic events that impacted the paleoenvironment of this region. Within the Cingulata, the Pampean Region fauna was probably dominated by glyptodonts with a high representation of Glyptodontinae and Neosclerocalyptinae while within the sloths the highest diversity and abundance is found in the Mylodontinae and Scelidotheriinae. These four clades represent both species with high ecological tolerance (e.g., Glyptodon munizi; Catonyx tarijensis) and ecologically highly specialized species (e.g., Neosclerocalyptus paskoensis; Scelidotherium leptocephalum). The presence of such ecological diversity underlines the status of the Pampean Region as a major interest for paleoecological and paleoenvironmental reconstruction.
Supplementary information:
The online version contains supplementary material available at 10.1186/s13358-023-00265-7.
... By contrast, both Thaumastocyoninae and Amphicyoninae tend to reduce the premolars, but the earliest members of these two subfamilies from the Paleogene still retain the primitive unreduced premolars, unlike the new specimen. For instance, the earliest thaumastocyonine Ysengrinia tolosana from MP 30 and the amphicyonine Cynodictis from the late Eocene have a well-developed p4 with a posterior accessory cuspid and a p3 with two roots, while Cynodictis has a much smaller size than Y. tolosana and the new specimen (Kuss, 1965;Bonis, 1978;Heizmann and Kordikova, 2000;Solé et al., 2021). The amphicyonine Pseudocynopsis and Cynelos from Quercy, France, have reduced, spaced premolars, but p2-4 retains two separate roots (Ginsburg, 1965;Kuss, 1965). ...
Records of Paleogene arctoids are scarce in Asia, but there are abundant records in Europe and North America. In this study, we report a new arctoid taxon, Lonchocyon qiui gen. et sp. nov., from the late Eocene Baron Sog Formation of the Erlian Basin, Inner Mongolia, China. This is the first report of a relatively complete, large arctoid taxon from the Erlian Basin. The new taxon is characterized by its overall large size; a deep mandible with a marginal process and a rudimentary premasseteric fossa; and much-reduced premolars, including p4, sectorial carnassial m1 with basined talonid, and unreduced m2-3. Lonchocyon exhibits a combination of morphologies present in both amphicyonids and the early ursid hemicyonines. The mandibular force profiles suggest that Lonchocyon could have delivered powerful canine bites while subduing prey, like large felids do today, and it may have occupied a specialized ecological niche as a predator consuming both soft flesh and hard objects.
The phosphorites of the Quercy from SouthWest France are well known for fossils preserved in 3D with phosphatized soft-tissues. Given that phosphatization is known to favor fine cellular preservation, the present study delves into the histological analysis of white and brown bones of Cainotheriidae (Artiodactyla) recently excavated from the DAM1 site near Caylus. Microscopy revealed that the white bones were completely filled with bacterial erosions, while the brown bones showed a pristine histology and intralacunar content resembling fossilized osteocytes in some areas. After decalcification, a brown bone revealed an abundance of blood vessel-like structures, innumerable osteocyte-like structures with canaliculi and a few chondrocyte-like structures, while a white bone revealed only blood vessel-like structures that looked eaten away. All the data combined suggest the brown bones were shielded from bacterial attacks and were filled with fossilized organic matter and original biological structures. The data taken all together do not support that these structures are casts, but indeed original and endogenous cells. This study encourages further histochemical and mineralogical analyses on Quercy fossils and the unique taphonomy of DAM1 to better understand fossilization processes and their impact on the color of bones, the chemistry of skeletal tissues, soft tissues, and cells.
The Oligocene (33.9–23.03 Ma) had warm climates with flattened meridional temperature gradients, while Antarctica retained a significant cryosphere. These may pose imperfect analogues to distant future climate states with unipolar icehouse conditions. Although local and regional climate and environmental reconstructions of Oligocene conditions are available, the community lacks synthesis of regional reconstructions. To provide a comprehensive overview of marine and terrestrial climate and environmental conditions in the Oligocene, and a reconstruction of trends through time, we review marine and terrestrial proxy records and compare these to numerical climate model simulations of the Oligocene. Results, based on the present relatively sparse data, suggest temperatures around the Equator that are similar to modern temperatures. Sea surface temperatures (SSTs) show patterns similar to land temperatures, with warm conditions at mid- and high latitudes (∼60–90°), especially in the Southern Hemisphere (SH). Vegetation-based precipitation reconstructions of the Oligocene suggest regionally drier conditions compared to modern times around the Equator. When compared to proxy data, climate model simulations overestimate Oligocene precipitation in most areas, particularly the tropics. Temperatures around the mid- to high latitudes are generally underestimated in models compared to proxy data and tend to overestimate the warming in the tropics. In line with previous proxy-to-model comparisons, we find that models underestimate polar amplification and overestimate the Equator-to-pole temperature gradient suggested from the available proxy data. This further stresses the urgency of solving this widely recorded problem for past warm climates, such as the Oligocene.
The Paleogene mammals of Europe are rarely known from partial or complete skeletons. As a result, their systematics and ecology are often solely based on dental characters and postcranial remains, when available, are usually neglected. This explains why the locomotion of mammals of the Eocene-Oligocene transition, the “Grande Coupure”, is poorly known. The aim of this study is to describe the tarsal bones (astragali and calcanei) and characterize the locomotion of amphicyonid carnivorans, one of the most abundant mammalian predator groups from the Phosphorites du Quercy (France) sites. The identification of taxa and the characterization of both posture and locomotion were carried out using four criteria: relative abundance (in comparison with dental data), morphology, size, and body mass. Seven morphotypes, four among astragali and three among calcanei, are identified as Amphicyonidae and show various postures: plantigrade, semi-digitigrade, and digitigrade. One morphotype of the astragalus and one of the calcaneus are identified as Cynodictis lacustrisGervais, 1852, which exhibits a digitigrade posture. The study of postcranial bones, such as tarsals, allows for a better understanding of the ecology of these animals and deserves more interest in future morphological and phylogenetic studies.
The confrontation of two independant approaches, magnetostratigraphical analysis and numerical ages provided by evolutionary lineages, led to a cross validation of the temporal calibration of the mammalian biochronological time scale from the European continental Paleogene. After a reinterpretation ofthe contradictory points, each method corroborates the calibration proposed. This comparison led to a numerical calibration of the European MP reference levels, which allows, as an hypothesis, a correlation with the international ret-erence time scales. Calibration RÉSUMÉ La conliontation de deux approches indépendantes. analyse magnétostratigraphique et âges numériques fournis parles lignées évolutives, permet une validation croisée des hypothèses formulées sur l'étalonnage temporel de l'échelle biochronologique mammalienne du Paléogène d'Europe occidentale obtenu par ces deux approches. Chacune des méthodes conforte l'étalonnage proposé, après une réinterprétation des points divergents. Cette confrontation permet une calibration numérique de l'échelle des niveaux-repères MPeuropéens. L'étalonnage permet également, à titre d'hypothèse, une corrélation avec les échelles de référence internationale.
After the previous lacking evidence allowed the interpretation of a non-deposition episod, the newly recorded mammal fauna from Puycelci (Tarn, SW France, close South to the Quercy paleokarstic area) now shows the MP 26 standard level (Late Oligocene, Early Chattian) being represented within the Eastern Aquitaine molassic basin filling. According to the evolutionary stage of known mammal lineages, the most significant Puycelci fossils are the Issiodoromys pauffiensis rodent and the Metriotherium cf. sarelense nov. sp. (described in this paper) artiodactyl ungulate. This new dating exemplifies the improvement of the mammalian biochronologic record as regards both the Quercy paleokarst and the surrounding lacustrine Tertiary basins W, S, and S-E to the Quercy, as well as, directly E and N-E, the smaller tectonic Tertiary basins within the crystalline Massif Central basement. The updated record shows the strong extension in time of the paleokarstic data, down to the Middle and Early Eocene, and up to the Early Miocene. Regarding the classically reported Late Eocene to Late Oligocene span, as well in the paleokarst and the peripheral basins, the available biochronological data now attains a valuable density level, the variation of which is significant. On one side there are periods (Late Eocene, Early Oligocene, Early Late Oligocene) with high biochronologic density, allowing improved time resolution using evolutionary stages within mammalian lineages (e.g. numerical ages). Such periods corresponds to almost continuous sedimentary processes, with only possible short breaks. On the other side, there are periods with unreported data, shared in the paleokarst and peripheral basins (Late Oligocene as best example). Such periods may well correspond to some non-deposition episods as once alleged by geologists. Then the surrounding biochronologic data would bear constraining value regarding these episods
The Paleogene mammals of Europe are rarely known from partial or complete skeletons. As a result, their systematics and ecology are often solely based on dental characters and postcranial remains, when available, are usually neglected. This explains why the locomotion of mammals of the Eocene-Oligocene transition, the “Grande Coupure”, is poorly known. The aim of this study is to describe the tarsal bones (astragali and calcanei) and characterize the locomotion of amphicyonid carnivorans, one of the most abundant mammalian predator groups from the Phosphorites du Quercy (France) sites. The identification of taxa and the characterization of both posture and locomotion were carried out using four criteria: relative abundance (in comparison with dental data), morphology, size, and body mass. Seven morphotypes, four among astragali and three among calcanei, are identified as Amphicyonidae and show various postures: plantigrade, semi-digitigrade, and digitigrade. One morphotype of the astragalus and one of the calcaneus are identified as Cynodictis lacustrisGervais, 1852, which exhibits a digitigrade posture. The study of postcranial bones, such as tarsals, allows for a better understanding of the ecology of these animals and deserves more interest in future morphological and phylogenetic studies.
Fossil material from 90 fossil localities, mostly paleokarstic, has been gathered together to study western European bat evolution and diversity from the middle Eocene (~44 Ma) to the early late Oligocene (~29 Ma). The morphological and biometric observations and comparisons of the tooth material allow recognition of 7 families, 10 genera and 57 species; amongst the latter, 45 are described in detail here together with 11 subspecies. Several taxa of various systematic ranks are described as new: 1 subgenus and 17 species including 6 new subspecies; 1 new family and 2 new genera were described in a previously published paper but originate from this large review. From these new results, and the long period covered (more than 10 Ma), this work suggests a number of phyletic hypotheses. Amongst others, the relationship between the new fossil family Mixopterygidae and the fossil and extant families Emballonuridae and Hipposideridae is discussed. The peculiar Necromantis fossil genus being now better documented, its particular inferior molar pattern is exemplified as defining the necromantodont pattern. Even though the affinities of Necromantis remain unclear, the new data indicate that the previous assignment to Megadermatidae was incorrect. Thanks to the available information from the bat material, the relative dating of yet unstudied and undated new localities is proposed from biochronal reference stages, characterized by some bat species with a given size and morphology. Also, further data are given for faunas dated by the numerical ages method. The comparison of fossil and modern bat cenograms suggests that the body weight composition of a community is linked to the nature of the environment in which it evolves. Finally, these analyses allow deducing some possible bat evolutionary modalities either by the variations in the represented weight range or by the proportion of the different weight categories. They indicate that extinctions preferentially affected “extreme species” from a morphological point of view, as well as in terms of body mass. Consequently, this allows discussion of the effect of Stehlin’s faunal Grande Coupure faunal event amongst western European bats at the Eocene–Oligocene boundary.
Résumé : L’étude des rongeurs Theridomorpha permet de suivre le déroulement d’une radiation adaptative pendant toute sa durée (Eocène moyen-Oligocène terminal), sur un territoire restreint à l’extrémité ouest de l’Europe Occidentale. Dans ce papier, la phylogénie de ce groupe est établie à partir d’une analyse cladistique reposant sur l’examen de 315 caractères (310 dentaires). Le groupe d’intérêt comprend 110 des 32 espèces (24 genres) de Theridomyoidea et deux genres encore inclus jusqu’ici dans les Reithroparamyinae qui rejoignent les Theridomorpha. Les groupes externes comprennent des glires basaux, Cocomys, Tanquammys et 16 Ischyromyiformes. Un cadre phylogénétique robuste est produit, qui permet de clarifier la systématique des Theridomorpha. La position des Remyoidea (nov. supfam.) au sein des Ischyromyiformes, extérieure aux Theridomorpha, est confortée. Les Protadelomys et Tardenomys sont à la base des Theridomyoidea, avant la séparation en deux clades correspondant aux familles Pseudosciuridae et Theridomyidae. Les sous-familles sont consolidées : Pseudosciurinae et Sciuroidinae pour les Pseudosciuridae ; Issiodoromyinae, Oltinomyinae, Columbomyinae, Theridomyinae, auxquelles s’ajoute au moins une nouvelle sous-famille (Patriotheridomyinae), pour les Theridomyidae. Les chrono-espèces (sensu Simpson), traitées antérieurement comme lignées évolutives, apparaîssent dans la plupart des cas sous forme de clades successifs, émergeant dans l’ordre stratigraphique. L’analyse des caractères aux principaux noeuds permet de consolider les caractères diagnostiques des taxons et les tendances évolutives, et de discuter des divers parallélismes et convergences dans l’évolution des structures et patrons dentaires (e.g., émail des incisives unisérié chez les Issiodoromyinae et les Patriotheridomyinae, ou pseudo-multisérié chez les Blainvillimys les plus hypsodontes, les Protechimys et Archaeomys ; patrons dentaires téniodontes ; allongement des dents déciduales chez les Patriotheridomyinae, Issiodoromyinae et Theridomyidae ; sélénodontie ou lophodontie). Les dynamiques évolutives traduites par les changements morphologiques sont mises en relation avec les variations environnementales. Enfin, les implications biochronologiques de l’évolution des Theridomyoidea sont discutées. //
Abstract: The adaptive radiation of the rodents Theridomorpha occurred during a limited time window (middle Eocene to late Oligocene), on an area restricted to Western Europe. In this paper, the phylogeny of this group is established via a cladistic assessment of 315 morphological characters (310 dental). The group of interest encompasses 110 upon 132 species (24 genera) of Theridomyoidea, and two genera formerly included within the Reithroparamyinae, and which are included here within the Theridomorpha. The outgroups include basal glires, Cocomys, Tanquammys and 16 Ischyromyiformes. A robust pylogenetic frame is produced, which allows clarifying the systematics of the Theridomorpha. Within the Ischyromyiformes, the Remyoidea (nov. supfam.) are set apart from the Theridomorpha. Protadelomys and Tardenomys represent the earliest offshoots of the Theridomyoidea, before the dichotomy between Pseudosciuridae and Theridomyidae. This topology supports the former subfamilies Pseudosciurinae and Sciuroidinae within the Pseudosciuridae; and for the Theridomyidae: the Issiodoromyinae, Oltinomyinae, Columbomyinae, Theridomyinae, with at least one new subfamily (Patriotheridomyinae). The chronospecies (sensu Simpson), formerly considered as evolutionary lineages, appear in most cases as successive clades emerging in the stratigraphic order. The analysis of characters supporting the main nodes allows consolidating the diagnostic characters of the taxa and their evolutionary trends, as well as discussing the various cases of parallelism and convergence in the evolution of structures and dental patterns (e.g., uniserial incisor enamel for Issiodoromyinae and Patriotheridomyinae, or pseudo-multiserial for the most hypsodont Blainvillimys, Protechimys and Archaeomys; taeniodont dental patterns; lengthening of deciduous premolars for Patriotheridomyinae, Issiodoromyinae and Theridomyidae; selenodonty or lophodonty). Evolutionary dynamics are analysed with respect to environmental changes. Finally, biochronological implications of the evolution of Theridomyoidea are discussed.