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International audience; Peirosaurids form an extinct clade of terrestrial crocodylomorphs from the Cretaceous of Africa and South America. Here, we describe a new mandibular ramus attributable to Hamadasuchus cf. rebouli from the Albian-Cenomanian of La Gara Samani (Algeria). We propose an emended diagnosis for this taxon, originally described from a left dentary fragment from the Kem Kem Group of Morocco and discuss the assignment of the specimens currently referred to it. Using ontogenetic series of extant crocodylians, we show that several mandibular characters commonly used to differentiate between close taxa instead record intraspecific or ontogenetic variability. In contrast, reliable mandibular characters enable us to propose that the current taxonomic content of Hamadasuchus rebouli should be reduced to three specimens, pending future description of relatable cranial remains. Finally, we demonstrate the importance of mandibular characters in phylogenies, by recovering the new specimen from La Gara Samani as closely related to North African peirosaurids on the basis of a data matrix designed solely on mandibular characters.

Reconstructing dinosaur trophic structure prior to the Cretaceous–Paleogene (K–Pg) boundary may provide information about ecosystem organization and evolution. Using calcium isotopes, we investigate preserved biogenic isotope compositions in a set of dinosaur teeth from three continental formations from Alberta, Canada, to assess latest Cretaceous food web structure. Tooth enamel δ44/42Ca values are presented for tyrannosaurids (n = 34) and potential large herbivorous prey (n = 42) in the upper Campanian Dinosaur Provincial Park Formation, upper-most Campanian–Maastrichtian Horseshoe Canyon Formation, and upper Maastrichtian–lower Paleocene Scollard Formation, spanning the last ~10 m.y. of the Cretaceous. The influence of diagenesis is assessed in a subset sample through major and trace elemental concentrations and ultraviolet (UV) Raman spectra, which provides a framework for interpreting calcium isotope values. In the Dinosaur Park Formation, hadrosaurid δ44/42Ca values are systematically heavier than ceratopsid values, a difference that is interpreted to reflect niche partitioning among megaherbivores. Tyrannosaurid δ44/42Ca values are scattered but on average, they are 44Ca-depleted relative to herbivorous dinosaurs in all three formations. As interpreted from the Dinosaur Park data set, tyrannosaurids may have preferentially fed on hadrosaurids. These analyses offer possibilities for testing whether trophic structure among non-avian dinosaur ecosystems changed several millions of years prior to the K–Pg boundary.

International audience; Osteoderms of eight extant and extinct species of crocodylomorphs are studied histologically and morphologically. Most osteoderms display the typical "crocodilian" structure with a woven-fibered matrix surrounded by an upper and a lower parallel fibered matrix. The dorsal ornamentation of those specimens consists of a pit-and-ridge structure, with corresponding remodeling mechanisms. However, an osteoderm of Iberosuchus, studied here for the first time, differs in being nearly devoid of ornamentation; moreover, it shows strong bundles of straight Sharpey's fibers perpendicular to the surface in its lateral and dorsal walls, along with a rough plywood-like structure in its basal plate. This suggests that this osteoderm was more deeply anchored within the dermis than the other osteoderms studied hitherto. This peculiar structure might have been linked to a terrestrial ecology and a specific thermoregulation strategy. Some other notosuchians in our sample do not exhibit ornamentation on their osteoderms, as opposed to neosuchians. Considering current interpretations of osteoderm function(s) in crocodilians, our observations are discussed in reference to possible ecophysiological peculiarities of Notosuchia in general, and Iberosuchus in particular.

International audience; Sharks occupy all living environments of the marine realm as well as some freshwater systems. They display varied and flexible feeding behaviours, but understanding their diet remains challenging due to their elusive ecology and the invasiveness of stomach content analyses in regard of their threatened status. As a potential alternative, we discuss the variability in δ 44/42 Ca values recorded in the tooth enamel of size-graded individuals belonging to three species of large sharks with distinct diets (Isurus oxyrinchus, Hexanchus griseus and Carcharodon carcharias). The preliminary results highlight shifts in diet linked to ontogeny (I. oxyrinchus and H. griseus) and spatial distribution (C. carcharias) characterizing feeding behaviour in these species at individual and population level. These outcomes agree with the results of traditional stomach analyses supporting that nontraditional stable isotopes thus represent new perspectives for the study of modern and extinct shark ecology. In addition, for the first time, the Sr/Ca elemental ratios measured in H. griseus reflect sexual differences that could be interpreted in terms of spatial segregation or physiological heterogeneities.

International audience; This contribution describes the continental micro- and macrovertebrate fauna of Angeac-Charente (Berriasian, Early Cretaceous). The rich and diversified fauna includes at least 38 different vertebrate taxa from all major clades, and is represented by more than 50 000 specimens. The Angeac-Charente locality includes the most diverse earliest Cretaceous mixed continental bonebed and the only Lagerstätte known to date in the World, and it provides a good picture of a Purbeckian paleocommunity. It includes remarkable taxa such as a new ornithomimosaur, a large turiasaur, an helochelydrid turtle and numerous mammals. The vertebrate fauna of Angeac-Charente has beyond all a Purberckian character. Many exclusively European genera and species belong to families with an essentially Laurasian paleogeographic distribution. Some taxa nevertheless suggest dispersal events between Africa and Europe at the Jurassic/Cretaceous transition. The successive Charentese faunas of Chassiron (Tithonian), Cherves-de-Cognac (Berriasian) and Angeac-Charente improve our poor knowledge of the evolution of continental vertebrate faunas at the Jurassic/Cretaceous transition. Rather than reflecting an important faunal turnover between the Tithonian and the Berriasian, they record environmental changes related to the sea–level regression that characterizes the end of the Jurassic.; La faune de vertébrés continentaux, représentée à la fois par des macro- et des microrestes, du Berriasien d’Angeac-Charente est décrite ici. Cette faune riche et diversifiée comprend au moins 38 taxons différents de vertébrés provenant de tous les grands clades et est constituée de plus de 50 000 spécimens. Le gisement d ’Angeac-Charente est le plus diversifié des bonebeds mixtes et le seul Lagerstätte continental du Crétacé connu à ce jour dans le monde. Il donne une bonne image de la paléocommunauté purbeckienne. Cette dernière comprend des taxons remarquables tels qu’un nouvel ornithomimosaure, un grand turiasaure, une tortue hélochelydride et de nombreux mammifères. La faune d’Angeac-Charente présente avant tout un cachet purbeckien. De nombreux genres et espèces exclusivement européens appartiennent à des familles dont la répartition paléogéographique est essentiellement laurasiatique. Certains taxons suggèrent néanmoins des événements de dispersion entre l’Afrique et l’Europe à la transition Jurassique/Crétacé. Les faunes charentaises des gisements de Chassiron (Tithonien), de Cherves-de-Cognac (Berriasien) et d’Angeac-Charente améliorent nos connaissances sur l’évolution des faunes continentales à la transition Jurassique-Crétacé. Plutôt que de refléter un important renouvellement faunistique entre le Tithonien et le Berriasien, elles enregistrent les changements environnementaux liés à la régression globale qui caractérise la fin du Jurassique.

The island of Madagascar is home to a distinctive fauna and flora whose biogeographic history is not fully understood. Today’s crocodylian population consists of a single species, the Nile crocodile, Crocodylus niloticus, whose colonization of the island may be very recent. In Madagascar, the genus Crocodylus has so far been described from a single subfossil specimen dated at 385 years cal BP, offering limited perspectives for discussing the timing of its arrival. On the other hand, another crocodyline, the now-extinct endemic Voay robustus, has been reported from several late Holocene localities throughout the island. Because of the earlier age of Voay robustus, it has been suggested that Crocodylus followed the extinction of this endemic species. Here, we report on a significantly older occurrence of the genus Crocodylus, between 7670 and 7510 years cal BP. The taxonomic identity of crocodylian subfossil specimens throughout Madagascar should be reevaluated in the context of this new occurrence, which could alter hypotheses of crocodylian turnover and the potential human impacts on the island.

Early Pliocene hominin evolutionary scenarios proposed to date mostly rely on paleontological investigations from eastern Africa. Filling major geographical gaps in the fossil record could potentially invalidate these scenarios and stimulate development of improved theories. Based on published literature, no Pliocene fossil of continental vertebrates have been discovered in Western Africa and the situation is only slightly better in central and northern Africa. Here, we expand the Pliocene vertebrate continental fossil record to western Africa with the description of the Tobene fauna, a new fossiliferous Neogene locality from Senegal. We describe a diversity of large mammals, including at least ten taxa based on fragmentary remains recovered from alluvial channel deposits. Estimation based on weathering events and biochronology suggests an early Pliocene age. Most of these mammalian taxa were widely distributed over the African continent during the early Pliocene. Possible faunal correlations with eastern African localities call for continent-wide paleontological investigations.***************

International audience; Following our fieldwork in Paleogene deposits of Togo, we herein report cranial as well as postcranial elements belonging to the family Dyrosauridae. This assemblage is dated to the Late Paleocene (Thanetian) from two quarries in southern Togo. The specimens include a partial skull presenting two large supratemporal fossae and a massive occipital condyle; long and slender isolated teeth; amphicoelous vertebrae including several articulated ones; and two osteoderms devoid of carina. The morphology of the partial skull reveals similarities with some African longirostrine forms such as Rhabdognathus spp., although this attribution cannot be confirmed. Longirostrine forms, known in the late Paleocene and early Eocene of the Iullemmeden basin (Nigeria, Niger, Mali, Algeria) and in the phosphates of Morocco and Tunisia, is only represented in Thanetian levels in Togo. Different palaeoenvironmental settings seem to have characterized the various African basins during the lower Eocene, with consequences for the geographic distribution of dyrosaurids. These dyrosaurid remains confirm the presence of the family in Togo during the Paleocene and underline the fossiliferous potential of the coastal sedimentary basin in Togo and in the bay of Benin.; Suite à nos travaux de terrain dans les dépôts du Paléogène du Togo, nous rapportons des éléments crâniens et post-crâniens appartenant à la famille des Dyrosauridae. Cet assemblage de crocodiliens est daté du Paléocène supérieur (Thanétien) affleurant dans deux carrières au Sud du Togo. Les spécimens décrits sont représentés par un crâne partiel présentant de grandes fosses supratemporales et un condyle occipital massif ; des dents isolées effilées et cannelées; des vertèbres amphicoeles dont plusieurs articulées ; et deux ostéodermes dorsaux sans carène. La morphologie des restes crâniens semble similaire à certaines formes africaines longirostres telles que Rhabdognathus spp., bien qu’une telle attribution générique ne puisse être confirmée. Les formes longirostres, connues au Paléocène supérieur et à l’Eocène inférieur dans le bassin des Iullemmeden (Nigéria, Niger, Mali et Algérie), dans les phosphates du Maroc et de Tunisie, ne sont représentées au Togo qu’au Thanétien. Des évolutions paléoenvironnementales différentes semblent avoir caractérisé les divers bassins d’Afrique à l’Eocène inférieur, et ont probablement influencé la distribution géographique des Dyrosauridae. Ces restes inédits de Dyrosauridae confirment, d’une part, la présence de ce groupe au Paléocène au Togo et accentuent, d’autre part, le potentiel fossilifère du bassin sédimentaire côtier du Togo et des dépôts contemporains de la baie du Bénin.

International audience; 3D model of a Togocetus skull (Protocetidae, Cetartiodactyla)-2/3 Figure 1. 3D reconstruction of the cranium and teeth of ULDG-KPO1. A, lateral view of the left side of ULDG-KPO1; B, palatine view. Abbreviations: C, canine; iof, infraorbital foramen; M, molar; P, premolar. The cranium elements are in grey, canine in dark red, premolar in light red and molar in yellow. Scale bar represents 2 cm.

International audience; There is clues that calcium (Ca) isotope composition of vertebrate bioapatite is influenced by diet and trophic level. These clues however conflict with several cases of mammal species exhibiting Ca isotope compositions which are inconsistent with their trophic levels. These observations support that diet may not be the only factor driving the Ca isotope composition in mammalian enamel and bone. To investigate this question, we selected a 1 Calcium isotopic variability of cervid bioapatite modern Cervus elaphus population (Bauges Natural Regional Park, Alps, France) to serve as a model for Ca isotope physiology of cervids and other mammals. Subsequently, we reinvestigated the case of the fossil Rangifer tarandus population from Jaurens (Late Pleistocene locality, 32.6 to 29.7 kyr BP, France), a population for which abnormal 44 Cadepleted isotope compositions have been previously documented. By combining bone samplings and serial enamel micro-samplings, we discuss the main potential sources of Ca isotopic variability in bioapatite of young and adult individuals. This includes the effects of gestation, lactation, antlerogenesis, browser-grazer ecologies, osteophagia and natural mineral licks. Our results highlight an important effect of lactation on bone Ca isotope composition (δ 44/42 Ca = +0.18 ± 0.07 ‰; 95 % confidence interval), whereas other factors such as gestation or antlerogenesis seem more secondary. Our enamel micro sampling method allowed to detect when enamel Ca isotope composition could be affected by milk consumption or mineral supplementation. Thanks to these advances, we collected new data from the Pleistocene reindeers of Jaurens which are now consistent with their apparent low trophic level (corresponding to a herbivorous diet). This demonstrates that disentangling ecological and physiological signals within enamel Ca isotope compositions is possible by using serial micro-sampling. This approach allows retrieving accurate trophic information from this proxy and which, altogether, truly push forward the limits of Ca isotope applications regarding paleoecology, physiology and ethology.

International audience; The present contribution contains the 3D virtual restoration of a Pliocene right femur belonging to a Lutrinae indet. (Carnivora) from Tobène, Senegal, described and figured in Lihoreau et al. (2021) : "A fossil terrestrial fauna from Tobène (Senegal) provides a unique early Pliocene window in Western Africa ".

International audience; The Early Jurassic was marked by several episodes of rapid climate change and environmental perturbation. These changes culminated during the Toarcian Oceanic Anoxic Event (T-OAE), an episode of global warming that led to the widespread deposition of organic-rich shales. The Toarcian shales of NW Europe have also yielded exceptionally preserved fossils of marine vertebrates and invertebrates, but the potential links between the occurrences of these exceptionally preserved fossils and the T-OAE remain poorly investigated. Palaeontological excavations realized in Toarcian strata near Lodève (Hérault, southern France) have yielded several specimens of marine vertebrates and abundant invertebrate fauna. We have developed a multiproxy approach (ammonite biostratigraphy, X-ray diffraction-bulk mineralogy, Rock-Eval pyrolysis, stable isotopes, trace element, phosphorus and mercury contents) to place these findings in a well-defined temporal and palaeoenvironmental context, and hence constrain the factors that led to their remarkable preservation. The Jenkyns Event interval, unambiguously identified at the base of the Toarcian organic-rich shales by a 5‰ negative carbon isotope excursion, records higher mercury fluxes, which suggest a causal link with intense volcanic activity of the Karoo–Ferrar large igneous province. This interval is very condensed and unfossiliferous, and might have been deposited under abnormally low-salinity conditions. Our data show that the deposition of the vertebrate-yielding horizons post-dated the T-OAE by several hundreds of ka, and took place during a prolonged period of widespread oxygen-deficiency and elevated carbon burial. Our results indicate that the unusual richness in vertebrates of the studied site can be explained by a combination of regional factors such as warming-induced, prolonged seafloor anoxia, and more local factors, such as extreme condensation owing to reduced dilution by carbonate and detrital input.

Diplocynodon is a genus of basal alligatoroid comprising nine species, which spanned the late Palaeocene to middle Miocene of Europe. Despite recent revisions of most Diplocynodon species, one of the earliest named and most complete, Diplocynodon hantoniensis, has not been re-described for over 150 years. This species is known from the remains of numerous individuals from the Priabonian (late Eocene) Headon Hill Formation, which crops out at Hordle (Hordwell) Cliff in Hampshire, United Kingdom. Here we re-describe and diagnose Diplocynodon hantoniensis, providing the first detailed description of postcranial anatomy in Diplocynodon, and indeed any basal alligatoroid. Diplocynodon hantoniensis is diagnosed by four autapomorphies, including retention of the ectopterygoid–pterygoid flexure through ontogeny and a unique anterior process of the ectopterygoid adjacent to the posteriormost maxillary alveoli. A critical review of previously referred remains from elsewhere in Europe and the USA restricts Diplocynodon hantoniensis to the late Eocene of the UK. Through comparisons with extant crocodylians, the well-preserved postcranial skeleton enables the interpretation of numerous muscle attachments in the forelimbs and hindlimbs, providing a potentially rich source of character data for future phylogenetic analyses. Based on a comparison of humeral morphology between a large sample of crocodylian species, we outline two new morphological characters in the humerus. We include D. hantoniensis in a phylogenetic analysis, including all putative Diplocynodon species (103 taxa scored for 187 characters). We use four different character-weighting schemes: equal weighting, implied weighting (k value = 8) and extended implied weighting with k-values of 4 and 8. In general, these weighted analyses produce congruent results with the equal-weights analysis, and increase the resolution within Diplocynodon. We recover a monophyletic Diplocynodon in three of the four analyses. However, the fourth analysis, with the strongest downweighting of homoplastic characters and missing data (extended implied weighting with k = 4), recovers the Palaeocene Diplocynodon remensis outside Diplocynodon. Our comprehensive revision of one of the most completely known Diplocynodon species facilitates comparisons in the genus, as well as between other basal alligatoroids, and forms the basis for comparing postcranial anatomy in other fossil crocodylians.

International audience; The contribution of dairy products to modern human diets has a debated role in the expansion of Neolithic economies and the dynamics of demographic transitions. While current methods allow discussing dairy production and processing, no approach allows reconstructing quantitatively its effective consumption. Calcium isotopes (δ44/42Ca) potentially represent such a marker due to the abundance of isotopically fractionated Ca in dairy products. Here, we test Ca isotope sensitivity to dietary intake of dairy product: we first used a dietary model based on a compilation of available data of dietary Ca sources; we then compared the modelled outputs to available and newly acquired skeletal δ44/42Ca values of individuals from populations with documented and markedly distinct dairy consumption habits. Our model predicts a marked decrease of skeletal δ44/42Ca values with dairy Ca intake. We measure a significant difference in δ44/42Ca values between populations eating no dairy products and those with high proportions of dairy Ca in their diet. The average dairy Ca intakes inferred by the model agree well with the documented dietary habits of these populations. Finally, we observe a significant drift across Neolithic and Iron Age periods up to modern times in societies producing dairy, contrasting with the populations consuming no dairy products. This trend marks a dramatic change in the utilization of dietary Ca. Given the available data, our model supports a marked increase in dairy intake starting from the late Neolithic period in Western Europe. Calcium isotopes could yield significant insight into the evolutions of dairy product intakes and the biocultural revolutions experienced by Neolithic populations.

Lactation and gestation are among the physiological events that trigger the most intense changes in body calcium (Ca) fluxes. Along with the composition of the animal 2021 diet, these events are suspected to impact the Ca isotopic composition of Ca body reservoirs but their dynamics are poorly understood. In this study, we monitored a group of domestic sows across a full reproduction cycle. We collected tissues and fluids (blood, urine, milk, colostrum, umbilical blood, adult and piglet bones) at different steps of gestation and lactation, and analyzed their Ca isotopic compositions (i.e. δ44/42Ca) by means of multi-collector inductively coupled plasma mass spectrometry. Among other results, we report the first observations of Ca isotopic fractionation between maternal and umbilical blood (Δ44/42Caumbilical blood-sow blood = −0.18 ± 0.11‰, n = 3). Our data also highlight that gestation and lactation periods are characterized by small diet-bone Ca isotopic offsets (Δ44/42Cabone-diet = −0.28 ± 0.11‰, n = 3), with 44Ca-enriched blood compositions during nursing (Δ44/42Canursing blood-gestation blood = $+ 0.42{\rm{\,\,}}_{ - 0.12}^{ + 0.11}$‰, n = 3). Under the light of an up-to-date mammalian box model, we explored different scenarios of gestation and lactation Ca fluxes experienced by a sow-like animal. These simulations suggest that gestation changes on body δ44/42Ca values may result from the intensification of Ca absorption by the animal, whereas the production of 44Ca-depleted milk is the main driver for the 44Ca enrichment in blood during lactation. In addition, our results also support that bone mineralization could be associated with a more restricted Ca isotopic fractionation than previously envisioned. Together, these results refine the framework of Ca isotope applications, notably regarding the monitoring of human bone balance and the study of species and ecosystems from the present and the past.

International audience; Since the description of Isisfordia duncani, a number of new extinct species and revisions of previous species have prompted a variety of contradicting phylogenetic hypotheses on the 1

International audience; Dinosaur trackways have rarely been reported in Cretaceous strata across the African continent. To the exception of ichnological occurrences in Morocco, Tunisia, Niger and Cameroon, our knowledge on the composition of Cretaceous dinosaur faunas mostly relies on skeletal evidence. For the first time, we document several dinosaur trackways from the Cretaceous of the Mamfe Basin in western Cameroon. Small and medium-size tridactyl footprints as well as numerous large circular footprints are present on a single horizon showing mudcracks and ripple marks. The age of the locality is considered Cenomanian-Turonian and if confirmed, this ichnological assemblage could be younger than the dinosaur footprints reported from northern Cameroon, and coeval with or younger than skeletal remains reported from the Saharan region. These trackways were left in an adjacent subsiding basin along the southern shore of the Benoue trough during a time of high-sea stand when the Trans-Saharan Seaway was already disconnecting West Africa from the rest of the continent. We predict that other similar track sites may be occurring along the margin of the Benoue trough and may eventually permit to test hypotheses related to provincialism among African dinosaur faunas.

International audience; We report here three new elasmobranch fossil taxa from Thanetian-Lower Lutetian nearshore marine deposits of northeastern (Matam region) and central-western (Sine-Saloum region) Senegal. These three new taxa represent the oldest species of the enigmatical elasmobranch Odontorhytis, the oldest putative representatives of marine potamotrygonid, and an uncertain dasyatoid genus with the smallest grinding dentition ever described. These new taxa, representing the second Cenozoic elasmobranch remains formally described from Senegal, broaden our understanding of their evolutionary and biogeographic history in the equatorial Eastern Atlantic during this time period. Their occurrences confirm hypothesised stratigraphically correlations between the top of Matam Fm. and the base of Lam Lam Fm., refine the marine connections between these two Senegalese regions, and suggest that these genera were broadly distributed within the shallow marine settings of the equatorial Eastern Atlantic during latest Paleoceneearly Middle Eocene.; Nous rapportons ici trois nouveaux taxa de fossiles d’élasmobranches des dépôts marins littoraux du Thanétien–Lutétien inférieur du Nord-Est (région de Matam) et du Centre-Ouest (région du Sine-Saloum) du Sénégal. Ces trois nouveaux taxa représentent les espèces les plus anciennes d’élasmobranches énigmatiques appartenant au genre Odontorhytis, aux potamotrygonides marins et à un dasyatoïde avec la plus petite denture broyeuse jamais décrite. Ces nouveaux taxons, complétant l’unique description d’élasmobranches cénozoïques nouveaux au Sénégal, élargissent notre compréhension de leur histoire évolutive et biogéographique de l’Atlantique Est équatorial au cours de cette période. Leurs occurrences confirment des corrélations stratigraphiques hypothétiques entre le sommet de la Formation de Matam et la base de la Formation de Lam Lam. Celles-ci affinent aussi les liens marins entre ces deux régions sénégalaises et leur comparaison avec des occurrences reconnues en Afrique du Nord et de l’Ouest suggèrent que ces genres étaient largement répartis et diversifiés dans les environnements marins peu profonds de l’Atlantique Est équatorial au cours du Paléocène terminal et du début de l’Éocène moyen.

Teleosauridae and Metriorhynchidae were thalattosuchian crocodylomorph clades that secondarily adapted to marine life and coexisted during the Middle to Late Jurassic. While teleosaurid diversity collapsed at the end of the Jurassic, most likely as a result of a global cooling of the oceans and associated marine regressions, metriorhynchid diversity was largely unaffected, although the fossil record of Thalattosuchia is poor in the Cretaceous. In order to investigate the possible differences in thermophysiologies between these two thalattosuchian lineages, we analysed stable oxygen isotope compositions (expressed as δ18O values) of tooth apatite from metriorhynchid and teleosaurid specimens. We then compared them with the δ18O values of coexisting endo-homeothermic ichthyosaurs and plesiosaurs, as well as ecto-poikilothermic chondrichthyans and osteichthyans. The distribution of δ18O values suggests that both teleosaurids and metriorhynchids had body temperatures intermediate between those of typical ecto-poikilothermic vertebrates and warm-blooded ichthyosaurs and plesiosaurs, metriorhynchids being slightly warmer than teleosaurids. We propose that metriorhynchids were able to raise their body temperature above that of the ambient environment by metabolic heat production, as endotherms do, but could not maintain a constant body temperature compared with fully homeothermic ichthyosaurs and plesiosaurs. Teleosaurids, on the other hand, may have raised their body temperature by mouth-gape basking, as modern crocodylians do, and benefited from the thermal inertia of their large body mass to maintain their body temperature above the ambient one. Endothermy in metriorhynchids might have been a by-product of their ecological adaptations to active pelagic hunting, and it probably allowed them to survive the global cooling of the Late Jurassic, thus explaining the selective extinction affecting Thalattosuchia at the Jurassic–Cretaceous boundary.This article is part of the theme issue ‘Vertebrate palaeophysiology'.

International audience; The Early-Late Cretaceous transition (late Albian-early Cenomanian; ~100 Ma) witnessed marked environmental changes and a deep reorganization of the marine fauna. The impact of these environmental and biotic changes on Tethyan marine vertebrates is poorly understood, due to a fragmentary fossil record. Here we report upper Albian marine vertebrate remains, including a partially articulated plesiosaurian skeleton, from a fossiliferous glauconite-rich bed in the Alpes de Haute-Provence, France. The fossiliferous horizon produced a diversified invertebrate fauna including ammonoids and belemnoids. The ammonite fauna is abundant and diversified, indicating the Mortoniceras fallax ammonite Zone. The calcareous nannofossil biomarkers date the bed to the NC10a Zone. The fossiliferous bed consists of glauconitic marls enriched in planktic foraminifera and occurs amongst a monotonous succession of alternating marlstones and limestone beds. The vertebrate fauna consists of chondrichthyans and marine reptiles. Chondrichthyans are represented by five Lamniformes species (dominated by Sphenodus) and comprise predator taxa probably living in open marine temperate waters. The site yielded a large, partial post-cranial plesiosaurian skeleton with articulated elements belonging to an elasmosaurid and representing one of the most complete Albian plesiosaurian specimens known from Europe. The abundance and preservation of the collected fossil remains are best explained by their concentration during a basin-scale episode of very low sedimentation corresponding to a major episode of marine transgression, associated with a lower oxygenation of bottom waters. These findings indicate that the newly 2 discovered fossiliferous bed holds promising clues about the evolutionary history of major groups of marine vertebrates and ammonites near the Early-Late Cretaceous transition.

Calcium isotopic ratios in dental enamel of South African hominins reveal taxon-dependent nursing behaviors., Nursing is pivotal in the social and biological evolution of hominins, but to date, early-life behavior among hominin lineages is a matter of debate. The calcium isotopic compositions (δ44/42Ca) of tooth enamel can provide dietary information on this period. Here, we measure the δ44/42Ca values in spatially located microsized regions in tooth enamel of 37 South African hominins to reconstruct early-life dietary-specific variability in Australopithecus africanus, Paranthropus robustus, and early Homo. Very low δ44/42Ca values (

International audience; Skull and mandibular elements of a tomistomine crocodilian are described from the late Eocene to early Oligocene lignite seams of Krabi, peninsular Thailand. The Thai tomistomine is a longirostrine form characterized by a rostrum/skull ratio of about 0.6; a mandibular symphysis reaching the level of the eleventh alveolus; a deep participation of the splenial in the symphysis to the level of ninth alveolus; an enlarged fifth maxillary alveolus; long nasals reaching the premaxillae at the level of the fifth maxillary alveolus but not contributing to the external nares; undivided posterior processes of premaxillae; a short prefrontal, excluded by a longer lacrimal from the posteromedial margin of maxillae; vomers visible on the palate. A phylogenetic analysis recovers the Thai specimen among derived tomistomines, on the stem lineage of the extant Tomistoma schlegelii, as a close ally of Maomingosuchus petrolica, a late Eocene tomistomine from southern China. The present recognition of Maomingosuchus sp. in late Eocene Thai deposits expands the distribution of Eocene tomistomines from southern China to the tropics. The origin of Tomistominae in Asia is briefly discussed.; Des éléments crâniens et mandibulaires d’un crocodilien tomistominé sont décrits en provenance de niveaux à lignite de l’Eocène supérieur à Oligocène inférieur de Krabi sur la péninsule Thailandaise. Le tomistominé Thaïlandais est caractérisé par un crâne de type longirostre présentant un ratio rostre/crâne d’environ 0.6 ; une symphyse mandibulaire qui atteint le niveau du onzième alvéole ; une participation profonde du splénial dans la symphyse mandibulaire au niveau du neuvième alvéole ; un cinquième alvéole maxillaire élargi ; les os du nasal qui atteignent les prémaxillaires au niveau du cinquième alvéole maxillaire mais ne participant pas aux narines externes ; des processus postérieurs des prémaxillaires non-divisés ; un préfrontal court, exclu de la marge postéromédiale des maxillaires par un lacrimal plus long ; un vomer visible sur le palais. Une analyse phylogénétique place le spécimen Thaïlandais au sein des tomistominés dérivés, au sein de la lignée de l’actuel Tomistoma schlegelii, et proche de Maomingosuchus petrolica, un taxon de la fin de l’Eocène connu en Chine du sud. La présente découverte de Maomingosuchus sp. dans l’Eocène tardif de Thaïlande étend l’aire de répartition des tomistominés eocènes depuis la Chine du sud jusqu’aux tropiques. L’origine des Tomistominae en Asie est brièvement discutée.

International audience; Conodont animals are an extinct group of jawless vertebrates whose hard parts, also known as conodont elements, represent the earliest evidence of a mineralised skeleton in the vertebrate lineage. Conodont elements are interpreted as parts of a feeding apparatus, which together with the presence of eyes and microwear patterns, support the controversial hypothesis that conodont animals were macrophagous predators and/or scavengers. Here, we explore the trophic position of five conodont genera (Palmatolepis, Polygnathus, Ancyrodella, Ancyrognathus and Icriodus) from five contemporary Late Devonian sites distributed worldwide (France, Morocco, Vietnam and Australia) by means of calcium (Ca) stable isotope compositions. The seawater Ca isotope composition was calibrated using contemporary Late Devonian brachiopod isotopic values. By comparison with extant marine trophic chain composed of cartilaginous fish, conodont Ca isotope compositions are indicative of a zooplanktivore-primary piscivore niche, with no genus-specific trophic pattern. The question of active predation or scavenging cannot be resolved definitively but our results strongly suggest that Late Devonian conodonts were first level consumers.

We describe a partial dyrosaurid skeleton recently prepared out of a limestone block discovered in the 1930s from Danian strata along the Atlantic coast of Senegal. The specimen, from a single individual, comprises nicely preserved elements of the appendicular and axial skeleton from the abdominal and sacral region, which enables us to refine our knowledge on some postcranial characteristics of the Dyrosauridae. Although Dyrosauridae are abundant in early Eocene deposits of North Africa, the present discovery in the Danian of Senegal fills a patchier record early after the K/Pg boundary and provides an important comparative data point with the few other Danian dyrosaurid records such asAtlantosuchusfrom nearby Morocco orGuarinisuchusandHyposaurusfrom Brazil and the USA, respectively.

International audience; The calcium isotopic composition (δ44/42Ca) of bone and tooth enamel can be used for dietary reconstructions of extant and extinct mammals. In natural conditions, the δ44/42Ca value of bone and teeth varies according to dietary intake with a constant isotopic offset of about −0.6‰. Owing to the poor conservation of collagen, carbon (C), and nitrogen (N) isotopic compositions of the Regourdou Mousterian site (MIS 5, Dordogne, France) previously failed to provide any paleodietary information. Therefore, to reconstruct the trophic chain, we have measured calcium (Ca) isotopes from fossil bone samples of the fauna from the Regourdou site, as well as from three bone samples of the Regourdou 1 Neandertal specimen. The results show a taxon-dependent patterning of the Ca isotopic compositions: herbivores generally have higher δ44/42Ca values than carnivores. All the δ44/42Ca values of Regourdou 1 are low (

Cenozoic continental deposits of the Bugti Hills crop out south of the Sulaiman Range in Balochistan, Pakistan. These have been renowned since Vickary (1846) for their exceptionally rich vertebrate...

International audience; The core of the fossil record of Teleosauridae, a family of thalattosuchian crocodylomorphs, is well known from western Tethyan marine deposits of the Jurassic. Outside this province, their fossil record is patchy and in need of revision, with specimens from Russia, Madagascar, and Asia. Peipehsuchus teleorhinus is known from the Early or Middle Jurassic of China and teleosaurid specimens have been mentioned or preliminarily described from two Jurassic localities in Thailand, yet they were not assigned to a given taxon. Thanks to recent field work, at least 10 individuals represented by cranial material were excavated and prepared from a single Jurassic locality known as Phu Noi in the lower Phu Kradung Formation of northeastern Thailand. Here, we describe these specimens, together with disarticulated postcranial elements, and erect a new taxon, Indosinosuchus potamosiamensis, gen. et sp. nov. Phylogenetic analyses confirm the teleosaurid affinities of the new species, which does not form an exclusive clade with the Chinese teleosaurid Peipehsuchus teleorhinus. The presence of teleosaurids at Phu Noi and a preliminary account of its faunal content favor a Middle to Late Jurassic age for the fossil-bearing horizon. In contrast, Cretaceous deposits in Thailand are characterized by goniopholidids and pholidosaurids, indicating a faunal turnover in Southeast Asia across the Jurassic–Cretaceous. As previously shown by isotope data, the new teleosaurid species was a resident of the freshwater environment and co-occurs with remains of exclusively terrestrial taxa such as sauropod, ornithopod, and theropod dinosaurs and freshwater tetrapods such as turtles and temnospondyls.

International audience; The fossil record of the genus Gavialis currently harbors nine species, many of which were erected from the mid XIX th to early XX th century, sometime on the basis of incomplete specimens. A survey of the Natural History Museum of London collections, where many specimens were collected in the course of geological surveys in Punjab and Sindh, part of the former Indian Empire, provides a basis to reevaluate the taxonomic content of the genus Gavialis. Four species, G. leptodus, G. pachyrhynchus, G. curvirostris and G. breviceps, are not referable to the genus Gavialis. The species G. hysudricus is considered a junior synonym of G. gangeticus. The genus Gavialis includes two species namely G. gangeticus and G. bengawanicus; two others, G. browni and G. lewisi require revisions. Several similarities are noted between the tomistomine Rhamphosuchus crassidens and G. leptodus, G. pachyrhynchus, G. curvirostris and G. breviceps. As a generality, the scarcity of information on sampling locations renders difficult a discussion on taxon provenance and age. However, a definitive revision of these taxa requires a revision of R. crassidens as well as an improved stratigraphic framework for all these taxa in a continuing effort to update the diversity of Gavialis and other longirostrine forms in the Mio-Plio-Pleistocene of India-Pakistan and SE Asia.

A long hiatus encompassing most of the Eocene (end of the Ypresian to the early Priabonian) breaks up the proboscidean evolutionary history, which is otherwise documented by a rich fossil record. Only two post-Ypresian localities from West Africa (Mali and Senegal) have yielded scarceMoeritherium-like dental remains. Here, we study one of these remains from Senegal and name a new genus and species,Saloumia gorodiskii. This taxon, confidently mid-Lutetian in age, evokesMoeritheriumand elephantiforms with its wrinkled enamel, lack of centrocrista, and strong lingual cingulum. However, due to its pronounced bunodonty, which departs from the bunolophodonty of bothMoeritheriumand elephantiforms, we cannot exclude the possibility thatSaloumiadocuments an early experiment in dental diversity among Paleocene–Eocene proboscideans, without direct relationships with later proboscideans.UUID:http://www.zoobank.org/0b6b83f8-817d-498c-a672-8ffa8f81a978

International audience; The present 3D Dataset contains the 3D model analyzed in Vautrin et al. (2019), Palaeontology, From limb to fin: an Eocene protocetid forelimb from Senegal sheds new light on the early locomotor evolution of early cetaceans.

Machimosaurus is a large teleosaurid thalattosuchian, a marine crocodylomorph historically recovered from Upper Jurassic strata of Europe. Several fragmentary remains are assignable to this genus but only four complete skulls have been reported, two of which are currently unavailable for study. A recent revision of the material assigned to Machimosaurus recognizes four valid species in this genus. Following a critical review of the diagnostic features of the various species, we confirm that the genus Machimosaurus is monospecific with Machimosaurus hugii as the sole and unique representative. (C) 2015 Academie des sciences. Published by Elsevier Masson SAS. All rights reserved.

Calcium isotope analyses show a depletion of heavy calcium isotopes in vertebrates, compared to food sources along each trophic step. Recent studies show considerable variability of the calcium isotopic composition of bone and teeth in modern mammals, leading to inconclusive interpretations regarding the utility of Ca isotopes for trophic inference in mammal-dominated terrestrial ecosystems. Here, we analyzed modern enamel samples from the Tsavo National Park (Kenya), and fossil enamel samples dated from ca. 4 Ma to 1.6 Ma from the Turkana Basin (Kenya). We found a constancy of taxa ordering between the modern and fossil datasets, suggesting that the diagenesis of calcium isotopes is minimal in fossils. In modern herbivore samples using similar digestive physiologies, browsers are enriched in Ca-44 compared to grazers. Both grazer and browser herbivore tooth enamel is enriched in Ca-44 relative to carnivores by about +0.30 parts per thousand. Used together, carbon and calcium isotope compositions may help refine the structure of the C-3 and C-4 trophic chains in the fossil record. Due to their high preservation potential, combining both carbon and calcium isotope systems represent a reliable approach to the reconstruction of the structure of past ecosystems. (C) 2018 Eisevier B.V. All rights reserved.

International audience; Weaning practices differ among great apes and likely diverged during the course of human evolution, but behavioral inference from the fossil record is hampered by a lack of unambiguous biomarkers. Here, we show that early-life dietary transitions are recorded in human deciduous tooth enamel as marked variations in Ca isotope ratios (δ 44/42 Ca). Using a sequential microsampling method along the enamel growth axis, we collected more than 150 enamel microsam-ples from 51 deciduous teeth of 12 different modern human individuals of known dietary histories, as well as nine enamel samples from permanent third molars. We measured and reconstructed the evolution of 44 Ca/ 42 Ca ratios in enamel from in utero development to first months of postnatal development. We show that the observed variations of δ 44/42 Ca record a transition from placental nutrition to an adult-like diet and that Ca isotopes reflect the duration of the breast-feeding period experienced by each infant. Typically, the δ 44/42 Ca values of individuals briefly or not breastfed show a systematic increase during the first 5-10 mo, whereas individuals with long breastfeeding histories display no measurable variation in δ 44/42 Ca of enamel formed during this time. The use of Ca isotope analysis in tooth enamel allows microsampling and offers an independent approach to tackle challenging questions related to past population dynamics and evolution of weaning practices in hominins. calcium isotopes | tooth enamel | dietary transitions | weaning | breast milk

Crocodilian remains from the late Palaeocene continental locality of Mont de Berru (Marne, France) offer the opportunity to reassess the taxonomic identity of the oldest diplocynodontid from Europe. Owing to significant morphological differences from previously described species of Diplocynodon, which include the presence of a splenial symphysis, a new species, Diplocynodon remensis sp. nov., is erected here. Its inclusion in a phylogenetic framework for Eusuchia leads to its positioning as a derived member of diplocynodontids. Diplocynodontidae are viewed as a basal alligatoroid taxon, and, because morphological affinities with the Late Cretaceous−early Eocene North American genus Borealosuchus were mentioned in earlier studies, a comparison amongst D. remensis sp. nov., Leidyosuchus, and Borealosuchus spp. is presented. Although D. remensis sp. nov. is the geologically oldest diplocynodontid, according to our results, it is not the phylogenetically most primitive. Other morphological discrepancies are highlighted, indicating that the topology recovered here is only tentative. From a biogeographical point of view, the appearance of Diplocynodon in Europe prior to the Palaeocene/Eocene boundary indicates that it did not disperse with North American taxa that reached Europe around the time of the Palaeocene-Eocene thermal maximum (PETM). Therefore, a pre-PETM dispersal from North America at the same times as other vertebrates with clear North American affinities also occurring in the Palaeocene of Europe cannot be excluded. The description of D. remensis sp. nov. adds substantial new, albeit conflicting, information, highlighting the need for a better phylogenetic framework with a revision of other critical taxa (Menatalligator, Borealosuchus) from the Palaeocene of Europe and North America. © 2014 The Linnean Society of London

Mesozoic marine reptiles went through a severe turnover near the end of the Triassic. Notably, an important extinction event affected ichthyosaurs, sweeping a large part of the group. This crisis is, however, obscured by an extremely poor fossil record and is regarded as protracted over the entire Norian-earliest Jurassic interval, for the lack of a more precise scenario. The iconic whale-sized shastasaurid ichthyosaurs are regarded as early victims of this turnover, disappearing by the middle Norian. Here we evaluate the pattern of this turnover among ichthyosaurs by analysing the faunal record of two Rhaetian localities. One locality is Autun, eastern France; we rediscovered in this material the holotypes or partial `type' series of Rachitrema pellati, Actiosaurus gaudryi, Ichthyosaurus rheticus, Ichthyosaurus carinatus and Plesiosaurus bibractensis; a revised taxonomic scheme is proposed. The second assemblage comes from a new locality: Cuers, southeastern France. Both these assemblages provide several lines of evidence for the presence of shastasaurid-like ichthyosaurs in the Rhaetian of Europe. These occurrences suggest that both the demise of shastasaurids and the sudden radiation of neoichthyosaurians occurred within a short time window; this turnover appears not only more abrupt but also more complex than previously postulated and adds a new facet of the end-Triassic mass extinction.

Millimeter-scale growth rings in canine dentine of MIS 3 cave bears have been interpreted as annual growth bands produced, in part, by seasonal variation in growth rate. We present new intra-tooth stable carbon (δ13C) and oxygen (δ18O) isotope profiles in dentine hydroxylapatite of early forming permanent teeth, from three famous Late Pleistocene cave bear sites from Romanian Carpathians. We measured δ13C and δ18O of the CO3 fraction of dentine hydroxylapatite from samples covering a profile across the root, representing a general line from juvenile period to adulthood. Carbon isotopes measured in dentine samples – from the first to the last to be deposited – of the same individual, record an increase in δ13C values throughout immature life of bears as has been shown previously, with lower precision, using age categories. For the first time, based on δ13C data analysis, the weaning process in cave bears was identified. The δ18O values show substantial variations related, most probably, to seasonal growth of the dentine. Finally, the CO3 of dentine apatite extracted from cave bear canines proves to be reliable for geochemical analyses, reflecting physiology, behavior and palaeoclimatic conditions.

The fourth complete skull of the marine crocodilian Machimosaurus von Meyer, 1837 is hereby described together with an associated complete mandible and disarticulated postcranial elements from the Kimmeridgian of Neuffen, Germany. Although the genus has been described fairly recently on the basis of two nearly complete skulls, their state of preservation did not allow a thorough examination of the entire skull anatomy. Here, we add new information with the description of nicely preserved cranial and mandibular elements of a single individual attributable to Machimosaurus hugii von Meyer, 1837. The diagnosis is updated for the genus and for the species M. hugii and challenges the validity of the second species M. mosae (Liénard, 1876). Moreover, previous assumption that Steneosaurus obtusidens Andrews, 1913 is a junior synonym of Machimosaurus hugii is not supported by our observations. Notably, M. hugii differs from S. obtusidens by a lower tooth count, the morphology of the dentition, the shape of the supratemporal fenestrae and the absence of an antorbital fenestra. Comparative anatomy and a phylogenetic analysis show that Machimosaurus is more closely related to the genus Steneosaurus than to Teleosaurus cadomensis (Lamouroux, 1820). doi:10.1002/mmng.201300009

The fourth complete skull of the marine crocodilian Machimosaurus von Meyer, 1837 is hereby described together with an associated complete mandible and disarticulated postcranial elements from the Kimmeridgian of Neuffen, Germany. Although the genus has been described fairly recently on the basis of two nearly complete skulls, their state of preservation did not allow a thorough examination of the entire skull anatomy. Here, we add new information with the description of nicely preserved cranial and mandibular elements of a single individual attributable to Machimosaurus hugii von Meyer, 1837. The diagnosis is updated for the genus and for the species M. hugii and challenges the validity of the second species M. mosae (Liénard, 1876). Moreover, previous assumption that Steneosaurus obtusidens Andrews, 1913 is a junior synonym of Machimosaurus hugii is not supported by our observations. Notably, M. hugii differs from S. obtusidens by a lower tooth count, the morphology of the dentition, the shape of the supratemporal fenestrae and the absence of an antorbital fenestra. Comparative anatomy and a phylogenetic analysis show that Machimosaurus is more closely related to the genus Steneosaurus than to Teleosaurus cadomensis (Lamouroux, 1820). doi:10.1002/mmng.201300009

International audience; The collapse of marine ecosystems during the end-Cretaceous mass extinction involved the base of the food chain [1] up to ubiquitous vertebrate apex predators [2–5]. Large marine reptiles became suddenly extinct at the Cretaceous-Paleogene (K/Pg) boundary, whereas other contemporaneous groups such as bothremydid turtles or dyrosaurid crocodylomorphs, although affected at the familial, genus, or species level, survived into post-crisis environments of the Paleocene [5–9] and could have found refuge in freshwater habitats [10–12]. A recent hypothesis proposes that the extinction of plesiosaurians and mosasaurids could have been caused by an important drop in sea level [13]. Mosasaurids are unusually diverse and locally abundant in the Maastrichtian phosphatic deposits of Morocco, and with large sharks and one species of elasmosaurid plesiosaurian recognized so far, contribute to an overabundance of apex predators [3, 7, 14, 15]. For this reason, high local diversity of marine reptiles exhibiting different body masses and a wealth of tooth morphologies hints at complex trophic interactions within this latest Cretaceous marine ecosystem. Using calcium isotopes, we investigated the trophic structure of this extinct assemblage. Our results are consistent with a calcium isotope pattern observed in modern marine ecosystems and show that plesiosaurians and mosasaurids indiscriminately fall in the tertiary piscivore group. This suggests that marine reptile apex predators relied onto a single dietary calcium source, compatible with the vulnerable wasp-waist food webs of the modern world [16]. This inferred peculiar ecosystem structure may help explain plesiosaurian and mosasaurid extinction following the end-Cretaceous biological crisis.

International audience; The recent development of multi-collector induc-tively coupled plasma mass spectrometry (MC-ICP-MS) notably in the disciplines of earth sciences, now allows the precise measurement of isotope ratios, even at low concentration. Non-traditional isotope systems, such as alkaline earth (Ca, Mg) and transition (Cu, Fe, Zn) metals are now being measured in a variety of biological tissues, including bone and teeth. Although our understanding of the environmental and biological mechanisms behind the fractionation of such elements is still in its infancy, some of these isotopes are suspected to fractionate along the food chain, as has been reported in the literature for calcium, magnesium and zinc. Other geochemical methods, such as concentration analyses, permit a prior assessment of diagenesis in the fossils and such an approach indicates that in some circumstances, not only enamel but also dentine or bone can preserve its original bio-genic composition. The aims here are to: review the current knowledge surrounding these various isotopic tools; address their potential preservation in biological apatite; and provide the palaeobiologist with a guide to the different toolkits available , including a discussion of their potential applications in vertebrate palaeobiology with a case study involving two mammal assemblages from the Pleistocene of Europe.

Skull fragments and osteoderms assigned to Iberosuchus sp. are described from three middle Eocene localities: Aumelas, Robiac and Saint-Martin-de-Londres in Languedoc, southern France. These remains expand the anatomical knowledge of this poorly known taxon, notably on the morphology of the premaxilla, maxilla, postorbital and jugal and allow a comparison with other non-eusuchian ziphodont mesoeucrocodylians. A close relationship of the genus Iberosuchus with narrow/elevated-snouted Baurusuchidae or Peirosauridae from the Cretaceous of South America and Africa appears unlikely. Affinities between Iberosuchus and Sebecidae, a group reported from the Cenozoic of South America; are suspected but require further testing. The record of Iberosuchus is limited to the European middle Eocene (Lutetian and Bartonian) and it is currently known from Portugal, Spain and France.

Goniopholidids and pholidosaurids are common crocodilians in Late Jurassic and Early Cretaceous freshwater environments in many parts of the world, although evidence that goniopholidids ever reached Gondwanan regions needs to be substantiated. In the ‘mid’-Cretaceous, some pholidosaurids (Terminonaris, Oceanosuchus) became adapted to life in the sea, a domain that goniopholidids apparently never occupied. Whereas goniopholidids were mainly mesorostral forms, pholidosaurids were longirostral. There is currently no consensus about the phylogenetic relationships between goniopholidids and pholidosaurids. They have been considered as closely related on the basis of various shared characters (Buffetaut, 1982), but in some recent phylogenetic analyses (e.g., Jouve et al., 2006; Jouve, 2009; Pol et al., 2009) at least some pholidosaurids cluster with other longirostral forms such as dyrosaurids and thalattosuchians, which may suggest that the family Pholidosauridae is not monophyletic. Nevertheless, a number of characters uniting Pholidosauridae have recently been proposed (Hua et al., 2007), but were not tested in a phylogenetic framework. On the other hand, only one unambiguous character diagnoses the clade Goniopholididae in phylogenetic studies: the presence of a depression on the posterior end of the maxilla, described as the ‘depression maxillaire’ (maxillary depression) by Buffetaut (1982; see also Lauprasert et al., 2007). On this basis, Goniopholididae is accepted as a monophyletic entity comprising the generaCalsoyasuchus,Goniopholis,Eutretauranosuchus, Siamosuchus, and Sunosuchus (Tykoski et al., 2002; Lauprasert et al., 2007; Smith et al., 2010), thus agreeing with pre-cladistic views (Buffetaut, 1982). Functionally, the maxillary depression may have housed a sensory organ helping to localize and capture prey in the aquatic environment (Brandalise de Andrade, 2009). Here, we report for the first time the presence of a maxillary depression in Pholidosauridae. Its morphology and position is for the first time described in taxa where the maxillojugal area is preserved. Implications for a close relationship between Goniopholididae and Pholidosauridae are discussed on the basis of this previously overlooked character. Institutional Abbreviations—AMNH, American Museum of Natural History, New York, U.S.A.; BYU, Brigham Young University, Provo, Utah, U.S.A.; CHE, Universite Lyon 1, Lyon, France, specimen from Cherves de Cognac; CMNH, Cleveland Museum of Natural History, Cleveland, Ohio, U.S.A.; DORCM, Dorset County Museum, Dorchester, United Kingdom; MNHN, Museum National d’Histoire Naturelle, Paris, France;MNN, Musee National du Niger, Niamey, Republique du Niger; NHMUK, The Natural History Museum, London, United Kingdom.