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International audience; Amber and plant remains were discovered in the lower Cenomanian lignitic clay from La Gripperie-Saint-Symphorien (Charente-Maritime, western France). The amber mainly consists of scarce and infracentimetric pieces showing a wide range of sizes and colours. The shape of the amber grains greatly varies, including more or less cylindrical fragments of flows and spherical drops. Plants consist of foliar remains corresponding to isolated pinnae and pinnules of ferns (Matonia sp., Weichselia reticulata (Stokes & Webb, 1824) Fontaine emend. Alvin, 1971), leafy axes of conifers (Geinitzia reichenbachii (Geinitz, 1842) Hollick & Jeffrey, 1909, Pagiophyllum sp.) and leaves of angiosperms (including cf. Eucalyptolaurus depreii Coiffard, B.Gomez, Thiébaut & J.Kvaček and three morphotypes of undeterminable leaves). They are preserved as isolated cuticles, charcoalified compressions without cuticle, and external casts. Angiosperms are clearly the most abundant and diverse remains of the plant assemblage. This latter contrasts with most of Albian-Cenomanian coastal floras from the Aquitaine Basin, which are dominated by gymnosperms characterised by xeromorphic adaptations and tolerating halophytic conditions. Similar to the coeval sites of Puy-Puy (Charente-Maritime) and Jaunay-Clan (Vienne), the plant-rich clay from La Gripperie-Saint-Symphorien was probably deposited in innermost coastal environments heavily influenced by inland/continental freshwater.; De l’ambre et des plantes ont été découverts dans les argiles ligniteuses du Cénomanien inférieur de La Gripperie-Saint-Symphorien (Charente-Maritime, Ouest de la France). L’ambre correspond principalement à de rares pièces infracentimétriques qui montrent une large gamme de tailles et de couleurs. La forme des grains varie beaucoup, incluant des fragments de coulées plus ou moins cylindriques, ainsi que des gouttes sphériques. Les plantes correspondent à des pennes et pinnules isolées de fougères (Matonia sp., Weichselia reticulata (Stokes & Webb, 1824) Fontaine emend. Alvin, 1971), des axes feuillés de conifères (Geinitzia reichenbachii (Geinitz, 1842) Hollick & Jeffrey, 1909, Pagiophyllum sp.), ainsi que des feuilles d’angiospermes (incluant cf. Eucalyptolaurus depreii Coiffard, B.Gomez, Thiébaut & J.Kvaček et trois morphotypes de feuilles indéterminées). Ces restes sont préservés sous forme de cuticules isolées, compressions charbonneuses sans cuticule et moulages externes. Les angiospermes constituent les restes les plus abondants et les plus diversifiés de l’assemblage paléobotanique. Ceci contraste avec la plupart des flores littorales de l’Albien-Cénomanien du Bassin Aquitain, dominées par des gymnospermes montrant des adaptations xéromorphiques ainsi qu’une tolérance aux conditions halophytiques. Similairement aux sites contemporains de Puy-Puy (Charente-Maritime) et Jaunay-Clan (Vienne), les argiles à plantes de La Gripperie-Saint-Symphorien ont probablement été déposées dans des environnements côtiers plutôt internes et fortement influencés par de l’eau douce.

Body fossils have been discovered in the Fortunian deposits of the Rozel Cape, in Normandy (NWFrance). The material consists of about 80specimens preserved on a shale surface, recently observed at the base of a cliff at the Cap Rozel, in the Cotentin region. The fossils, centimetric in size, have an elliptical outline, with a peripheral bulge, generally without other conspicuous ornamentation, but showing sometimes concentric or radial lines possibly of taphonomic origins. In addition, these body fossils are preserved parallel to the bedding plane, locally rich in horizontal trace fossils (e.g. Archaeonassa Fenton& Fenton, 1937, Helminthoidichnites Fitch, 1850, Helminthopsis Heer, 1877) and also complex treptichinids burrows (e.g.Treptichnus pedum (Seilacher, 1955)) sometimes associated with microbial mats. The sedimentological characteristics of these deposits (ripple marks, syneresis cracks) correspond to a shallow marine shelf environment, with a variable hydrodynamism in the intertidal zone, low for surfaces showing elliptic fossils and syneresis cracks, higher for surfaces with ripple marks. These new discoveries unravel the potential of the Fortunian strata from Normandy and provide new information about the early Cambrian biocenoses.

International audience; PremiseThe conifer Geinitzia reichenbachii was a common member of the Cretaceous Laurasian floras. However, the histology of G. reichenbachii leafy axes was never described in detail, and our knowledge of its paleoecology remains very limited. Using new and exquisitely preserved silicified material from the Upper Cretaceous of western France, we describe G. reichenbachii from the gross morphology to the cellular scale, then discuss paleoecological and taphonomical implications.MethodsWe examined specimens from two localities in western France (Claix and Moragne) using propagation phase-contrast X-ray synchrotron microtomography.ResultsThe cuticle and the inner tissues of leafy axes are preserved in three dimensions. Epidermis, hypodermis, palisade parenchyma, spongy parenchyma, transfusion tracheids, and most of tissues of the vascular cylinder are clearly discernible. The numerous resin ducts are sometimes filled by persisting resin. Additionally, surfaces of some leaves preserved drops and flows of resin.ConclusionsDepositional environmental context combined with histological features of G. reichenbachii suggest that this conifer was adapted to a range of marginal-littoral ecosystems including those open to the sea paleoenvironments and innermost ones influenced by strong continental inputs. Geinitzia reichenbachii was adapted to withstand intense sunlight, hot temperatures coupled with salty sea wind, and dry conditions. The frequent amber-bearing beds in the Cretaceous from western France with Geinitzia as a main component of the associated floras raises the possibility of a role for Geinitzia in the production of the “Charentese amber”.

Néraudeau, Didier, Philippe, Marc, Albani, Abderrazak El, Moreau, Jean-David, Polette, France, Martin, Jean-Paul Saint (2022): Taphonomie et minéralisation de bois carbonatisés du Purbeckien de l'Usine, à Cherves-Richemont (Charente). Geodiversitas 44 (24): 665-682, DOI: 10.5252/geodiversitas2022v44a24

International audience; Fragments of filled wood‐borings were recently discovered from the Eocene–Oligocene Conglomerate and Sandstone Formation of the Malzieu Basin (Lozère, southern France). Propagation phase‐contrast X‐ray synchrotron microtomography (PPC‐SRμCT) was used to characterize their hidden inner structures. Virtual 2D sections and 3D reconstructions show that the inner microstructures of borings display a mudstone–wackestone siliceous matrix including tiny coprolites. The hexagonal cross‐section of these coprolites is characteristic of termite faecal pellets. Morphology and dimensions of the coprolites share strong similarities with those of extant Kalotermitidae (drywood termites). The depositional environment is interpreted as a fluvial valley in which the lenticular sandstone and conglomerate lenses correspond to channels. This discovery complements the record of Palaeogene termites which remain poor in France and throughout the world.

International audience; Plants and insects are the two dominant groups in terrestrial ecosystems, and insect damage on fossil plants is the only direct evidence documenting the past ecological history between these two, hyperdiverse groups. We describe, analyze, and interpret plant–insect interactions of a lower Cenomanian paleoforest from western France – the Puy-Puy Quarry of the Nouvelle-Aquitaine Region. We examined 1605 fossil leaves, axes, and reproductive material of bennettitalean, pinalean, and ginkgoalean gymnosperms; lauralean and magnolialean angiosperms; and pteridophyte fronds. We identified functional feeding groups (FFGs) and insect damage types (DTs) preserved on this foliage and data were rarified to indicate sample completeness. By employing R, various statistical parameters were calculated. We established 71 DTs for the nine FFGs of hole feeding, margin feeding, skeletonization, surface feeding, oviposition, piercing and sucking, galling, mining, and pathogens, and 1292 feeding event occurrences. Of the specimens examined 22.2% exhibited one or more DT, with angiosperms the most affected plant group. The most diverse interactions were mining and galling, indicating a mosaic of humid and xeric habitats, respectively, for the Puy-Puy paleoforest, a conclusion consistent with previous paleontological and sedimentological interpretations. Elevated DT richness suggests long-standing ecological relationships between the plants and insects, representative of a mature forest.

International audience; The presence of “geological” amber (or “succin” in old French monographs) has been reported for several centuries in the Mesozoic deposits of Provence, southeastern France. Diverse amber-bearing sites were inventoried by the authors but their location and stratigraphical context remain unclear for most of them. In the past decades, various data concerning chemistry, palaeontological content and comparison with archaeological discoveries improved our knowledge of the ambers of Provence, but only those of Cretaceous age. The present paper aims at providing a comprehensive description of all the presently known amber-bearing deposits of Provence, including the description of new sites. We highlight the great potential of Provence ambers and allow to consider a wider time range, from the Early Cretaceous to the Miocene.; La présence d’ambre « géologique » ou « succin » a été signalée en Provence depuis plusieurs siècles. Un certain nombre de gisements ambrifères crétacés, plus ou moins bien localisés précisément, avaient été ainsi répertoriés. Plus récemment des données variées concernant la chimie, le contenu paléontologique, la comparaison avec des ambres archéologiques ont amené à mieux connaître les ambres, uniquement d’âge crétacé, de la région. La présente revue des gisements ambrifères de Provence, incluant la découverte de nouveaux sites ambrifères, permet de mettre en évidence le potentiel en ambre de la Provence et d’envisager un large éventail de temps jusqu’à présent inenvisagé allant du Crétacé inférieur au Miocène.

International audience; The Puy-Puy quarry at Tonnay-Charente (Charente-Maritime, SW France) is a sand quarry exposing a 9-m-thick series of latest Albian–earliest Cenomanian (mid-Cretaceous) age. The uppermost Albian deposits consist of lignitic clay containing fossiliferous amber. The lowermost Cenomanian sand deposits alternate with clay intercalations containing plant remains. One of these clay levels, named P1, shows an outstanding accumulation of conifer and angiosperm macrofossils including delicate reproductive structures such as flowers. Plant remains are associated with invertebrates such as insects (Odonata, Dictyoptera, Diptera), crustaceans (Mecochirus sp.), putative brachiopods (aff. Lingula sp.), and worms. A few vertebrate remains such as shark egg capsules (Palaeoxyris sp.) and a feather are present in the fossil assemblage, as well as an enigmatic specimen tentatively interpreted as a cephalochordate or a petromyzontiform. Various ichnofossils occur in abundance, such as crustacean coprolites and burrows (Ophiomorpha isp.), insect coprolites (Microcarpolithes hexagonalis), and leaves with grazing structures, galls and mines. The sediments have been deposited in a coastal, calm and brackish area.

International audience; The origin of the diatoms still remains enigmatic. Their fossil record is scarce until the Late Cretaceous and great divergences exist between molecular data and the earliest fossil evidence. While molecular data indicate an origin during the Triassic or Early Jurassic, early fossil evidence is only from the Late Jurassic-Early Cretaceous. The discovery of diatoms in French mid-Cretaceous amber by the end of the 2000s already suggested a potential bias in the diatom fossil record as it made older many diatom lineages, the record of which hitherto began at the end of the Cretaceous. The Jurassic/Early Cretaceous fossil record of diatoms is extremely sparse and any new occurrence is important for retracing the evolutionary, palaeogeographical and palaeoenvironmental history of diatoms. Thai amber has yielded a new diatom specimen that has been attributed to the genus Hemiaulus . Fossil assemblages and sedimentological data indicate that Thai amber and its Hemiaulus specimen are Late Jurassic in age. This discovery represents the oldest hitherto known specimen of Hemiaulus and so extends the fossil record of the bipolar diatoms and of the genus Hemiaulus by several dozens of millions of years and brings closer the fossil evidence and molecular data (that estimated an origin of the bipolar diatoms about 150 Ma ago). It reinforces the hypothesis of a pre-Cretaceous fossil diatom records and also supports an origin of the diatoms in shallow coastal environments.; L’origine des diatomées reste toujours énigmatique. Leur registre fossile est rare jusqu’au Crétacé supérieur et il existe de grandes différences entre les données moléculaires et les premières évidences fossiles du groupe. Tandis que les données moléculaires indiquent une origine durant le Trias ou le Jurassique inférieur, les plus anciennes traces fossiles sont seulement de la fin du Jurassique, début du Crétacé. La découverte de diatomées dans l’ambre médio-crétacé français à la fin des années 2000 avait déjà suggéré un potentiel biais dans le registre fossile des diatomées car cela vieillissait plusieurs lignées précédemment connues uniquement à partir du Crétacé supérieur. Le registre fossile des diatomées du Jurassique et du Crétacé inférieur est extrêmement limité et toute nouvelle occurrence est importante pour retracer l’histoire évolutive, paléogéographique et paléoenvironnementale des diatomées. L’ambre de Thaïlande a permis la découverte d’un nouveau spécimen de diatomée attribué au genre Hemiaulus . Les données paléontologiques et sédimentologiques attestent que l’ambre thaïlandais et la diatomée qu’il contient sont d’âge Jurassique supérieur. Cette découverte représente le plus ancien spécimen du genre Hemiaulus connu à présent et étend donc le registre fossile des diatomées bipolaires et du genre Hemiaulus de plusieurs dizaines de millions d’années et rapproche ainsi le registre fossile des données moléculaires (qui estimaient l’origine des diatomées bipolaires à environ 150 millions d’années). Cela renforce l’hypothèse d’un registre fossile pré-crétacé et soutient une origine des diatomées au sein d’environnements marins néritiques.

Fossil inclusions of arthropods and microorganisms are abundant in the Cretaceous amber from western France, but plant meso- or macroremains are scarce. Preserved remains are mostly tiny, very fragmented, and indeterminable. Only one amber locality in the Charente department has already provided conifer remains. Here, we report the first plant mesoremains ensnared in Cenomanian amber from Fouras – Bois Vert, in the Charente-Maritime department. They consist of three well-preserved leafy axes and one cone of Cheirolepidiacean conifers. Based on the helical arrangement of rhomboidal, longer than wide, and highly adpressed leaves, leafy axes are ascribed to the genus Pagiophyllum. The ovoid cone bears more than 15 imbricate, helically arranged, scale-like leaves and is ascribed to Classostrobus sp. Although Cretaceous flora is abundant in lignitic clay from the Charentes region, Pagiophyllum is reported for the first time in Albian-Cenomanian deposits from this area. Xerophytic features of Pagiophyllum further support a harsh and instable coastal environment seasonally exposed to hot, dry conditions during the mid-Cretaceous in the Charentes region.

International audience; Further to the work published by Néraudeau et al. six years ago, palynological matter recovered from the lignitic bone bed of Angeac in Charente (south-west France) has been re-examined in order to provide more evidence of its age, the previous Hauterivian–Barremian interpretation being regarded as controversial. The samples come from four sedimentological units, An2–An5, which together yielded an assemblage of 34 species, taxonomically dominated by palaeoecologically significant lygodiaceous verrucate spores, including eight species attributable to the genus Concavissimisporites and three species of Trilobosporites. A few bisaccate pollen grains, including Vitreisporites pallidus, have been recovered, but the gymnospermous pollen spectrum is clearly dominated by the cheirolepidiaceous genus Classopollis, its abundance diminishing progressively upwards from units An4 to An2. The great abundance and diversity of verrucate forms, along with the presence of other spores typical of Lower Cretaceous deposits, such as Aequitriradites verrucosus, and the scarcity of specimens referable to Cicatricosisporites, render this assemblage most similar to those of the Hastings Group of southern England, and the Bückeberg Formation in north-western Germany. The time of deposition is, therefore, more likely to have been Berriasian–Valanginian rather than Hauterivian–Barremian, as previously stated. The associated small assemblage of megaspores is consistent with this determination. Except for Trilobosporites and Concavissimisporites, the use of several other genera commonly applied to Mesozoic verrucate spores, such as Converrucosisporites and Impardecispora, is considered unnecessary. To support this assertion, a Principal Components Analysis has been carried out on 120 verrucate spores from sedimentological units An2–4, taking into account ten morphological variables. The results show that specimens attributable to Trilobosporites are well be separated from the main cluster, which corresponds to Concavissimisporites, underlining the futility of using more than two genera for the species concerned.

International audience; Late Jurassic and Early Cretaceous charophyte assemblages from the northern part of the Aquitaine Basin in south-west France are reviewed here to understand their palaeoecological, palaeobiogeographical and biostratigraphic features. Three sites were studied: the Tithonian-lower Berriasian of Chassiron, and the Berriasian of Cherves-de-Cognac and Angeac-Charente. Abundant porocharaceans, less abundant clavatoraceans and scarce characeans recorded in Cherves-de-Cognac and Angeac-Charente indicate that brackish water environments were substituted by freshwater environments eastwards. The occurrence of Clavator grovesii var. grovesii and morphotypes intermediate with C. grovesii var. discordis in the same areas is significant from a biostratigraphic viewpoint, since these species belong to the Maillardii, Incrassatus and Nurrensis European charophyte biozones, representing the Berriasian. This observation refutes a previous dating of the Angeac-Charente site and highlights the absence of Hauterivian–Barremian records in northern Aquitaine, which is in contrast to the more complete Lower Cretaceous record in southern Aquitaine. These contrasting records could be due to differences in the available sedimentary space produced by the opening of the Bay of Biscay during the Barremian.

A palynological analysis of 45 samples from six mid-Cretaceous amber-bearing outcrops from Charentes has been carried out. A total of 227 taxa have been recorded in the studied palynofloras. Palynological data support earlier evidence and indicate an early Cenomanian age for the assemblages. The heterogeneous compositions of the palynofloral assemblages indicate the existence of different coastal depositional settings with a variable but usually weak marine influence. The local vegetation was subdivided in various types including herbaceous formations integrating ferns and eudicots which may have colonised frequently-disturbed, fluvial, open environments and xeric arboreal communities dominated by Cheirolepidiaceae and probably integrating drought- and/or salt-tolerant angiosperms and ferns (Anemiaceae and Gleicheniaceae) and other gymnosperms (Araucariaceae, Ginkgoales and scarce Cycadales and Gnetales). The existence of riparian and freshwater wetland communities integrating taxodioids, aquatic and/or hygrophilous angiosperms, ferns, lycopods, mosses and clubmosses is proposed. Coastal/?lagoonal counterparts including plants tolerant to periodical floods by saline or brackish waters is suggested by palynological evidence. Conifer forests mainly integrating Pinaceae and Podocarpaceae in raised hinterlands may also be interpreted on the basis of taphonomical considerations. The wide variety of depositional settings inferred by the palynological data support enhanced transport capabilities for amber and/or a widespread occurrence of producers in local vegetation during the early Cenomanian.

International audience; Cretaceous fossil inclusions were recently discovered in silica-rich nodules from the diachronic alteritic deposits of the Moragne hill, Charente-Maritime, western France. Nodules contain marine organisms such as sponge spicules, putative algae, echinoids (Periaster undulatus Agassiz and Desor) and rudists (Sphaerulites foliaceus Lamarck; hippuritids and radiolitids). These inclusions co-occur with fragmented pin-nae of ferns as well as diverse structures of conifers including leafy axes (Geinitzia sp.; Glenrosa carentonensis Moreau, Néraudeau, Tafforeau and Dépré) and isolated ovu-late scales or subtending bracts of cones. The palaeontological assemblage shows that the alterites from Moragne are condensed deposits resulting from the alteration of the Cenomanian to Turonian-Senonian regional series. Conifer leafy axes display diverse kinds of preservation: permineralization in silica, empty external casts of the gross morphology, and casts filled by ferruginous siltstone. Propagation phase-contrast X-ray synchrotron microtomography revealed exceptional preservation of some leafy axes up to the cell level. We support a multi-phase silicification including at least: (1) a precocious phase occurring during the sedimentation of the Upper Cretaceous deposits or during the earliest diagenesis, and that could be linked with the abundance of sponge spicules; then (2) a late phase occurring during Eocene-Oligocene period that corresponds to a hard climate event with strong and long paedogenitic alteration associated with an important phase of silicification (nodulation). The alterites from Moragne are an uncommon example of long-term time-averaged deposits caused by compac-tion and selective dissolution of matrix in the context of a late continental weathering.

International audience; We describe here the palynological content from the lower Cenomanian plant-rich site of Jaunay-Clan (Vienne, western France), a site that previously yielded exceptional leaf impressions. Altogether, 184 species of palynomorphs have been identified, and two palynological intervals were recognized in the sedimentary sequence. The lower interval is characterized by the taxonomical and numerical dominance of spores of Gleicheniaceae, Cyatheales, and Anemiaceae, while the upper interval is characterized by an abrupt increase in the abundance of Classopollis and the appearance of dinocysts. This shift in the palynological composition, coupled with paleobotanical observations, is interpreted as reflecting a transition from a calm freshwater environment, with occasional droughts to an environment more open to very occasional marine inputs, such as an inner lagoon.The association of Tehamadinium coummia, Trichodinium spinosum, Tricolpites nemejcii, Retitricolporites decorosus, and Microreticulatiporites sacalii, coupled with the absence of Normapolles pollen grains, suggests that the Jaunay-Clan assemblage is early Cenomanian in age, corroborating the previous determination based on lithological and paleontological proxies. However, the Jaunay-Clan palynoflora is considered to be slightly younger than the numerous earliest Cenomanian assemblages described from Charente-Maritime, owing to its resemblance with mid-lower Cenomanian palynofloras from western France. The paleoflora and palynoflora from Jaunay-Clan are similar to other assemblages found in the upper Albian of Spain (Teruel Province), and in the Cenomanian of France and Czech Republic (Peruc-Korycany Formation, La Buzinie, Archingeay). The combined Jaunay-Clan palynoflora and paleoflora is considered to be the most diversified Cenomanian paleobotanical-palynological assemblage described so far in Western Europe.

Resume Une nouvelle espece d’Archiaciidae, A. ramitaensis nov. sp., a ete decouverte dans le Cenomanien superieur de Syrie. Elle est decrite et comparee aux autres especes d’Archiacia deja connues. La distribution paleobiogeographique des Archiaciidae et leurs affinites paleoecologiques sont discutees.

International audience; The global palaeobiogeography of early marsupialiform mammals is still poorly understood due to a meagre fossil record outside western North America. Here, two isolated teeth of a marsupialiform mammal from the lowermost Upper Cretaceous (lower Cenomanian) of southwestern France are described and referred to Stagodontidae, a dentally specialized group whose unambiguous members are so far known exclusively from the Upper Cretaceous of North America. The occurrence of stagodontids in Europe represents additional evidence of faunal exchanges between the two landmasses during the latest Albian–early Cenomanian interval, around 100 million years ago, and shows that early (mid-Cretaceous) marsupialiforms were more widely distributed than previously thought

International audience; A new Cenomanian amber- and plant-bearing deposit has been discovered at Neau, in the Mayenne department (France). The Cenomanian fossiliferous lignites are located in karst filling in a substratum of Cambrian limestones. The amber corresponds mainly to tiny millimetric grains, devoid of arthropod inclusions, but rich in microorganisms, especially the sheated bacteria Leptotrichites resinatus , and containing pollen grains ( Classopollis ) and wood fibers (Araucariacae or Cheirolepidiaceae). The lignites provide abundant conifer and ginkgoale cuticle fragments ( Frenelopsis , Eretmophyllum ) and a lot of palynomorphs ( e.g. Gleicheniidites senonicu s, Cyathidites , Deltoidospora , Appendicisporites and Cicatricosisporites ). The chemical signature of the amber suggests it was produced by conifers of the extinct family Cheirolepidiaceae. According to the palynological assemblage, the age of the lignites is upper lower Cenomanian or lower mid Cenomanian. The deposit environment corresponded to the upstream portion of a mangrove or the most inner part of a lagoon.; Un nouveau site à ambre et plantes du Cénomanien a été découvert à Neau, en Mayenne (France). Les lignites fossilifères cénomaniens sont localisés dans des remplissages de karsts développés dans des calcaires du Cambrien. L’ambre se présente essentiellement sous forme de grains millimétriques, dépouvus d’inclusions d’arthropode, mais riches en microorganismes, notamment en bactéries gainées de type Leptotrichites resinatus , et contenant des grains de pollen ( Classopollis ) et des fibres de bois (Araucariacae ou Cheirolepidiaceae). Les lignites fournissent d’abondants fragments de cuticules de conifères et de ginkgoales ( Frenelopsis , Eretmophyllum ) et une grande quantité de palynomorphes ( e.g. Gleicheniidites senonicu s, Cyathidites , Deltoidospora , Appendicisporites et Cicatricosisporites ). La signature chimique de l’ambre suggère qu’il a été produit par des conifères de la famille éteinte des Cheirolépidiacées. D’après l’assemblage palynologique, l’âge des lignites est Cénomanien inférieur tardif ou Cénomanien moyen basal. L’environnement de dépôt correspondait à la partie amont d’une mangrove ou la partie la plus interne d’un lagon.

International audience; Over recent decades, diverse structures ascribed to angiosperms, bennettitaleans, conifers, cycads, ginkgophytes and pteridosperms have been reported from the Cretaceous deposits of the Aquitaine Basin (southwestern France). However, Albian macrofloras remain uncommon in Aquitania as well as in France. The clay from the Archingeay-Les Nouillers quarries is one of the rare deposits of the Aquitaine Basin to yield Albian plant meso- and macro-remains. Although Albian plant-bearing beds are not accessible any more in these quarries, samples collected from excavations conducted at the end of the XXth century were deposited in the collections of the University of Rennes 1. This paper provides a synthesis of the meso- and macro-remains contained in these collections, including angiosperm leaves and leafy conifer axes, dated as Late Albian. Providing here an inventory of the Cretaceous meso- and macro-remains from the Aquitaine Basin, we compare the Albian flora from Archingeay-Les Nouillers with pre-Albian, Albian, Cenomanian, and Turono-Coniacian floras from other localities in southwestern France.

International audience; We describe and name Loxolenichnus stellatocinctus Breton and Wisshak igen. et isp. nov., a bioerosion trace fossil on an Upper Cenomanian oyster from Le Mans (France). This trace is attributed here to a parasitic gastropod. The characteristics of this ichnospecies are a combination of one or several, vertical or oblique, complete penetrations, and an asymmetrical attachment etching (fixichnion) with a diagnostic set of stellate grooves increasingly distinct towards the margin of the trace. By including two former Oichnus ichnospecies, Loxolenichnus halo comb. nov. and Loxolenichnus taddei comb. nov., Oichnus, is now constrained to pure predation traces (praedichnia). The numerous oysters collected from the Marnes à Pycnodonte biauriculata Formation show associated epibionts and encrusters as well as borers and scrapers. Encrusters comprise 24 taxa while bioerosion trace fossils comprise 17 ichnotaxa ranging from very rare (< 0.1%) to quite abundant (81%). The taphonomic history leading to an ex-situ condensation of these oysters is complex. Both the Gnathichnus and Entobia ichnofacies are represented on the shellgrounds, presumably alternatingly.

Background and Aims Terrestrial plant remains in fossilized tree resin are relatively common. However, histology and preservation of plants entombed in Cretaceous ambers remain poorly known. We report an exquisitely preserved conifer leafy axis from 100-million-year-old opaque amber of western France that is assignable to Glenrosa carentonensis Moreau, Neraudeau, Tafforeau & Depre. The purpose of this paper is to discuss the taphonomy and the use of microtomography for studies of palaeobotanical remains in amber. Methods A leafy axis was examined using propagation phase-contrast X-ray synchrotron microtomography with voxel sizes of 14·9, 1·4, and 0·7 μm. Key Results The conifer leafy axis described is preserved in three dimensions. Despite desiccation of the specimen within the surrounding amber, the cuticle, as well as most of inner tissues, is preserved in three dimensions down to the cellular level. Epidermis, palisade parenchyma, spongy parenchyma, transfusion tracheids and vascular bundles are clearly distinguished. Conclusions Gross morphology and histology of the specimen were revealed using synchrotron microtomography, allowing an unprecedented resolution for the study of soft-bodied plants entombed in amber. The study reveals a peculiar combination of authigenic and duripartic preservation as well as permineralization, and highlights the complexity of taphonomic processes that can occur in amber inclusions. This fossil demonstrates the difficulty of studying amber-preserved plant remains under certain conditions.

Stable carbon-isotope geochemistry of fossilized tree resin (amber) potentially could be a very useful tool to infer the composition of past atmospheres. To test the reliability of amber as a proxy for the atmosphere, we studied the variability of modern resin δ 13 C at both local and global scales. An amber δ 13 C curve was then built for the Cretaceous, a period of abundant resin production, and interpreted in light of data from modern resins. Our data show that hardening changes the pristine δ 13 C value by causing a 13 C-depletion in solid resin when compared to fresh liquid–viscous resin, probably due to the loss of 13 C-enriched volatiles. Modern resin δ 13 C values vary as a function of physiological and environmental parameters in ways that are similar to those described for leaves and wood. Resin δ 13 C varies between plant species and localities, within the same tree and between different plant tissues by up to 6‰, and in general increases with increasing altitudes of the plant-growing site. We show that, as is the case with modern resin, Cretaceous amber δ 13 C has a high variability, generally higher than that of other fossil material. Despite the high natural variability, amber shows a negative 2.5–3‰ δ 13 C trend from the middle Early Cretaceous to the Maastrichtian that parallels published terrestrial δ 13 C records. This trend mirrors changes in the atmospheric δ 13 C calculated from the δ 13 C and δ 18 O of benthic foraminiferal tests, although the magnitude of the shift is larger in plant material than in the atmosphere. Increasing mean annual precipitation and p O 2 could have enhanced plant carbon-isotope fractionation during the Late Cretaceous, whereas changing p CO 2 levels seem to have had no effect on plant carbon-isotope fractionation. The results of this study suggest that amber is a powerful fossil plant material for palaeoenvironmental and palaeoclimatic reconstructions. Improvement of the resolution of the existing data coupled with more detailed information about botanical source and environmental growing conditions of the fossil plant material will probably allow a more faithful interpretation of amber δ 13 C records and a wider understanding of the composition of the past atmosphere.

International audience; The Upper Cretaceous lignite deposits of La Garnache, Vendée (western France), consist of two lignitic clay series, Garnache 1 and Garnache 2, separated by a fault. The first series cropped out to the south of the fault during road works until 2002 but is now covered by an embankment. It has provided numerous pieces of amber containing arthropod and microorganism inclusions. The second lignitic series, exposed to the north of the fault, is rich in fossil wood but devoid of amber. Palynological analysis of Garnache 1 revealed several Normapolles species belonging to the genera Atlantopollis, Complexiopollis, Osculapollis, Plicapollis and Trudopollis, but larger forms typical of Senonian deposits are absent. By contrast, Garnache 2 proved to be dominated taxonomically and numerically by spores (Appendicisporites, Camarozonosporites, Gleicheniidites, Patellasporites, Stereisporites), associated with a few gymnosperm (Cerebropollenites, Phyllocladidites, Classopollis) and angiosperm (Liliacidites, Retitricolpites and a single specimen of the Normapolles Complexiopollis) taxa. Garnache 1 is, therefore, younger than Garnache 2, the latter being clearly Cenomanian in age whereas Garnache 1 is more likely to be Turonian. Lignitic clay of Garnache 1 contains numerous translucent, orange to red, pieces of amber. Vendean amber is rich in aquatic arthropods, such as tanaids and epicarideans (Crustacea), as well as marine or brackish siliceous microorganisms such as diatoms and sponge spicules. These aquatic inclusions indicate that resin-producing trees grew along and close to the seashore. The amber-bearing clay was deposited in a calm, estuarine or lagoonal, muddy environment.

International audience; Two fossil localities are reported on the "LGV SEA" railroad from the Lower Cenomanianof Jaunay-Clan (JC), near Poitiers, western France. The laminated mudstones yielded plantfossils including ferns (Cladophlebis, Osmundophyllum, Ruffordia goeppertii, Sphenopteris),conifers (Brachyphyllum, Dammarophyllum, Pagiophyllum), and terrestrial and aquaticfreshwater angiosperms (Eucalyptolaurus depreii, Ploufolia). They are associated with acoleopteran insect that shows systematic affinities to the modern subfamily Chrysomeli-nae (Chrysomelidae). This assemblage suggests connections with arborescent vegetationgrowing in calm freshwater environment. Brackish to marine invertebrates also occurand include a dakoticancroid crab (Brachyura, Podotremata, Dakoticancroidea) and a fewbivalves (Brachidontes). They suggest brackish episodes during pond sedimentation in acoastal environment. Lastly, vertebrates are represented by an isolated feather.

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The infaunal irregular echinoid, Tithonia oxfordiana, is described and compared to congeneric species previously described from Upper Jurassic and lowermost Cretaceous strata. This new species characterizes a monospecific echinoid assemblage, which occurs only in some places where deep-marine middle Oxfordian deposits are exposed in south-east France. Specimens are closely packed and clearly concentrated at the top of small carbonate chemoherms; a close connection of the echinoids with the emission of reduced chemicals, which were oxidized by chemoautotrophic bacteria, is highly probable. Based on general test shape and plate architecture, T. oxfordiana probably was a deposit feeder on chemosynthetic organic matter produced by such bacteria. In view of the fact that T. oxfordiana is the sole species of the Jurassic genus Tithonia known from Oxfordian strata, it is postulated that chemoherms possibly acted as refugia for these peculiar echinoids, which have an episodic record between the Callovian and Valanginian.

Thermal properties of French Cretaceous ambers were investigated and compared with other ambers from various sites of the world. The amber samples came from 10 different localities in southern France, in the Charentes, Languedoc, and Provence regions, ranging from Late Albian to Santonian in age. Thermogravimetric (TG) and Differential Thermogravimetric (DTG) profiles were obtained at heating rate of 10 K/min in air, starting from room temperature (20 degrees C) and reaching a maximum temperature of 700 degrees C. Elemental Analysis for total Carbon, Hydrogen, Nitrogen and Sulphur was also carried Out. The TG combustion profile of the resins started after 200 degrees C and complete combustion took place near 600 degrees C. The DTG behaviour is characterized by a main exothermal peak situated between 394 and 420 degrees C, accompanied by minor peaks and shoulders. The increasing value of the main exothermal peak correlates well to the increase of the age of the specimens, with a significant correlation coefficient (r = 0.7721, p = 0.0089). A significant correlation (r = 0.6728, p = 0.0004) is also found with other samples of different age and origin. By considering the whole pattern of DTG peaks, a possible fingerprinting model of the French ambers is evaluated by multivariate analysis. Cluster Analysis and Principal Component Analysis show the presence of several clusters, according to the geological age and possibly to the palaeobotanical origin. The elemental analysis is consistent with that of other Cretaceous samples from different sites of the world. Carbon and hydrogen are the main constituents (range 73-80% and 9.5-11.5% respectively). Sulphur is detected in small amounts (0.8-2.4%). Nitrogen is absent or appears as traces only (0-0.008%). Oxygen and other elements range from 4.6 to 16.8%. No successful Clustering was possible according to the elemental composition. Thermal analysis, completed with multivariate statistics, is a useful Source of information also for French ambers, as a help for identification of the age, diagenetic processes and palaeobotanical origin.

International audience; Eucalyptolaurus depreii gen. et sp. nov. is proposed for angiosperm leaves newly collected from uppermost Albian ­ lowermost Cenomanian of Charente-Maritime (western France). They consist of simple, narrow, elongate laminas with entire margins and intramarginal veins. The epidermal cells of adaxial cuticle shows small, rounded, blunt papillae outward that protrude inward and fuse together as rolls along and parallel to the margins, while the adaxial cuticle bears brachyparacytic stomatal apparatus that exhibit sunken guard cells and hair bases consisting of a thick-walled pore surrounded by radially arranged differentiated cells. Resin bodies occur inside the mesophyll. These characters closely resemble the lauroid taxa 'Myrtophyllum' and Pandemophyllum from the Cenomanian of the Czech Republic and Dakota (USA) respectively. The narrow angle of basilaminar secondaries and the whole suite of features in the guard cells (sunken guard cells embedded into subsidiary cells and stomatal ledges) strongly support close affinity with the Lauraceae. From the Cenomanian lauraceous reproductive organs and their related leaves already showed high disparity and diversity. In addition they displayed a broad ecological range from freshwater floodplains to brackish swamps. This combined to high diversity of reproductive organs suggest ecological radiation of Lauraceae by the Cenomanian.

Late Albian amber from Charente-Maritime (southwestern France) contains the first known marine diatoms preserved in a fossil resin. Approximately 70 inclusions were assignable to the genera Basilicostephanus, Coscinodiscus, Hemiaulus, Melosira, Paralia, Skeletonema, Stephanopyxis, Trochosira, ?Aulacoseira, and to the order Rhizosoleniales. Some of them are represented by several species. This diatom assemblage is mainly composed of colonial planktonic genera, which are typical for coastal shallow waters. The newly found amber inclusions extend the fossil record of four genera and one order from the Late Cretaceous and support certain molecular phylogenetic assumptions regarding the diversifi cation of marine diatoms in the Early Cretaceous. The unusual introduction of diatom shells from the beach or sea by wind, spray, or high tide onto the resin fl ows was possible because the amber forest grew close to the seashore.

International audience; Cenomanian paralic deposits of Charentes (southwestern France) have yielded abundant vertebrate microremains, including rather diversified continental taxa (e.g., frogs, turtles, crocodilians, dinosaurs, pterosaurs, lizards, and mammals). In this short report, the succession of faunal assemblages observed is briefly described in relation to palaeoenvironmental change resulting from the Cenomanian-early Turonian transgressive episode. Continental forms occur commonly in estuarine and shallow marine rocks of the lower part of the Cenomanian stage, but seem to be lacking in younger strata deposited in more open marine settings. Among an unexpected biodiversity, several non-marine groups (e.g., ziphodont crocodilians, carcharodontosaurid and troodontid dinosaurs, marsupial-like mammals) are recorded for the first time in the lower Upper Cretaceous of Europe, thus providing new palaeobiogeographical indications for this poorly documented part of the world.

The developmental stages of feathers are of major importance in the evolution of body covering and the origin of avian flight. Until now, there were significant gaps in knowledge of early morphologies in theoretical stages of feathers as well as in palaeontological material. Here we report fossil evidence of an intermediate and critical stage in the incremental evolution of feathers which has been predicted by developmental theories but hitherto undocumented by evidence from both the recent and the fossil records. Seven feathers have been found in an Early Cretaceous (Late Albian, ca 100 Myr) amber of western France, which display a flattened shaft composed by the still distinct and incompletely fused bases of the barbs forming two irregular vanes. Considering their remarkably primitive features, and since recent discoveries have yielded feathers of modern type in some derived theropod dinosaurs, the Albian feathers from France might have been derived either from an early bird or from a non-avian dinosaur.

International audience; The teeth of six dinosaur taxa (Carcharodontosauridae indet., Dromaeosauridae indet., Troodontidae indet., Brachiosauridae indet., Iguanodontoidea indet., and Nodosauridae indet.) are identified and described from the early Cenomanian of the Charentes region, western France. The composition and paleoecology of this coastal, insular fauna is discussed. The Charentes dinosaur assemblage shares affinities with Asiamerican and Gondwanan faunas. This clarifies and highlights the role of the European islands in the paleobiogeography of Cretaceous dinosaurs.

The purpose of this paper is to understand which parameters control the palaeoenvironmental distribution of Middle Cretaceous oysters. To reach this objective, the following two step analysis has been carried out. First, ten major Upper Albian to Lower Turonian outcrops from the northern part of the Aquitain Basin (SW France) (fig. 1) were analysed with respect to their sedimentological and palaeontological features (see fig. 2 for oyster distribution). They represent a time interval corresponding to a 2nd order transgression [Hardenbol et al., 1997; Néraudeau et al., 1997], characterised in the Charentes (North Aquitaine Basin) by a great variety of depositional environments and very rich in oyster assemblages [Videt, 2004]. According to previous authors [Moreau, 1993; Néraudeau et al., 1997; Platel, 1989, 1996], this series can be divided into seven lithological units, A to G, four units (A, B, C and G) being subdivided into two or three subunits (A1 and A2, B1 to B3, C1 to C4, G1 and G2). Apart from the sub-units A1 and Tu, which correspond to the Late Albian and Early Turonian respectively, all the lithological sub-units A2 to G2 correspond to the Cenomanian series. A and B belong to the lower Cenomanian, C1 to C3 to the middle Cenomanian, and C4 to G2 to the Upper Cenomanian. In terms of palaeoenvironments, unit A is considered as deposits of a sandy estuary (with local lignite layers) [Néraudeau et al., 2002, 2003; Perrichot, 2003], and unit B as shallow subtidal sand dunes [Vullo et al., 2003]. Unit C corresponds to the optimal development of a carbonate platform with rudists [Chéreau et al., 1997], unit D to a marly open shelf marly facies, unit E to an oyster bank mainly composed of Pycnodonte biauriculata [Dhondt, 1984], unit F to a moderately deep bioclastic facies colonised by rudist Ichthyosarcolites triangularis and, unit G, which forms progressively marly up-section, to progressive platform flooding at the Cenomanian-Turonian boundary. From the analysis of these different lithological units and subunits, the North Aquitaine Basin can be considered as a mixed siliciclastic-carbonate platform. Two main depositional systems have been identified, namely an open one and a closed one. The synthetic distribution of twelve kinds of oysters biofacies (bf1 to bf12) described in these units and subunits is summed up in figure 3 according to depositional type, lithology and depth. Based on the palaeoenvironmental distribution of Middle Cretaceous oysters in the northern part of the Aquitain Basin, the palaeoecological affinities of the nine marine species are discussed regarding seven main parameters i.e., oxygenation, water turbulence, salinity, turbidity, bathymetry, grain size, and substrate consistency (i.e. “hardground” VS “softground”) (fig. 4). Acutostrea aff. incurva (Nilson, 1827) (figs 4, 5h) and Curvostrea rouvillei (Coquand, 1862) (figs 4, 5i) are very rare species with a distribution that is still ambiguous. Apparently they preferred soft substrates and seem to have tolerated lowered oxygen levels. In addition, they are encountered in quiet, deep environments, i.e., the lower infralittoral to circalittoral zones sensu Néraudeau et al. [2001]. Ceratostreon flabellatum (Goldfuss, 1833) (figs 4, 5e) is not a prolific species but was widely distributed all over the carbonate platform. Nevertheless it is mainly marine and located in the infralittoral zone [sensu Néraudeau et al., 2001]. Gyrostrea delettrei (Coquand, 1862) (figs 4, 5g) might have been very widespread but is very rare. It was most abundant in marginal marine environments where it was the sole oyster that tolerated brackish water conditions. Pycnodonte biauriculata (Lamarck, 1819) (figs 4, 5d), in spite of its very short stratigraphic range (Naviculare Ammonite Zone), colonised a wide variety of environments. It is mainly a relatively medium water species (regarding to other species) [Stenzel, 1971; Harry, 1985; Freneix and Viaud, 1986], from the lower infralittoral zone [sensu Néraudeau et al., 2001] but it needed food-laden currents. Pycnodonte vesicularis (Lamarck, 1819) (figs 4, 5f) is also an ubiquitous species. However, in contrast to Pycnodonte biauriculata, it preferred deep, soft substrates (circalittoral and deeper ones? [Néraudeau and Villier, 1997]). Rastellum carinatum (Lamarck, 1806) (figs 4, 5c) and Rastellum diluvianum (Linne, 1767) (figs 4, 5b) exhibit an identical distribution pattern in spite of the fact that R. diluvianum is more selective than Rastellum carinatum. Carter [1968], Jablonsky and Lutz [1980] and Freneix and Viaud [1986] have already demonstrate that these species do not tolerate turbulent conditions but are particularly adapted to quiet water and soft substrates. The two species also do not tolerate salinity variations. Rhynchostreon suborbiculatum (Lamarck, 1801) (figs 4, 5a) is the most ubiquitous species in the Cenomanian of the Aquitain Basin. Videt and Néraudeau [2003] and Videt [2004] have already defined the parameters that affected its shape and its abundance. As the species does not occur in brackish water deposits, salinity seems to have been a major factor limiting its distribution.

International audience; A fossil echinoid preserved on a palaeolithic flint core (Tercis open-air site, near Dax, Landes, France). A flint core collected from the Les Vignes archaeological site (at Tercis, near Dax, Landes, SW France) comprises a silicified internal mould of a Cyclaster (Echinoid, Spatangoid). The nucleus is assumed to be Mousterian and is the single one known from Europe with a fossil echinoid shown off by the Knapper. Flint and fossil of the flint core and from the geological site are compared for documenting the provenance. We speculate about possible interpretations concerning the human Knapper's intention.; Un nucléus récolté sur le site archéologique de plein air des Vignes (Tercis-les-Bains, près de Dax, Landes) comporte un Cyclaster (échinide, spatangoïde) accolé au silex par sa face inférieure. Ce nucléus, attribué au Moustérien, est le seul connu en Europe comportant un oursin fossile mis en valeur par la taille. Le silex et les fossiles du nucléus et du contexte géologique ont été comparés pour discuter de la provenance du matériau. Diverses hypothèses sont présentées sur l'intérêt que le tailleur a pu porter au fossile.

espanolNew investigations in the Pliocene deposits of Challans (Vendee) have allowed to collect more than 3000 marsupiate echinoids, remarkably preserved. So, apical systems, especially the marsupium of the breeding temnopleurids T. (V.) bigoti and C. bardini, have been described and figured for the first time with complete specimens. Two new marsupiate species have been described: Arbacina hugueti nov. sp., third marsupiate species of the genus Arbacina to be known in the Neogene of western France after A. emmae NERAUDEAU, 2003 from the Messinian of Brittany and A. pareyni ROMAN, 1983 from the Pliocene of Normandy; Tremaster romani, new species and genus of temnopleurid, characterised by an uncommon supra-ambital tuberculation, with excressences of the test surrounding scrobiculated tubercles. A third new marsupiate echinoid, Coptechinus sp. A, has been found too, but it is very difficult to know if it is a new species or a new morphotype of C. bardini. Contrarily to previous interpretations, this study points out the high diversity of western European Neogene marsupiate echinoids, a diversity comparable to the one of Australian Neogene marsupiate echinoids. However, breeding species from Australia and western Europe are clearly different and similarities exist between these two marsupiate echinofaunas at the family level only. Indeed, both in Australia and western Europe, the breeding species of echinoids mainly belong to the temnopleurid family, with the austral genus Paradoxechinus, on the one side, the north European genera Temnotrema and Coptechinus, on the other side. Moreover, the arbaciids consist of three marsupiate species of the genus Arbacina in Europe when no breeding species of this family exist in Australia. On the contrary, several breeding irregular echinoids have been found in the Australian Tertiary deposits (Spatangoids and Clypeasteroids) when not any marsupiate irregular echinoid has been discovered at present in the western Europe Neogene deposits. francaisDes recoltes recentes dans le Pliocene de Challans (Vendee) ont permis de recolter plus de 3000 echinides marsupiaux, remarquablement preserves. Les appareils apicaux, notamment les marsupiums des temnopleurides incubants T. (V.) bigoti et C. bardini, ont ainsi pu etre decrits et figures pour la premiere fois a partir de specimens complets. Deux especes marsupiales nouvelles sont decrites : Arbacina hugueti nov. sp., troisieme espece incubante du genre Arbacina a etre decouverte dans le Neogene de l'Ouest de la France apres A. emmae, NERAUDEAU, 2003, du Messinien de Bretagne et A. pareyni, ROMAN, 1983 du Pliocene de Normandie ; Tremaster romani, espece et genre nouveaux de la famille des Temnopleuridae, caracterisee par une tuberculation supra-ambitale tres particuliere, avec des excroissances du test cernant des tubercules scrobicules. Une troisieme forme inedite, Coptechinus sp. A, a egalement ete mise en evidence, mais sans que l'on puisse affirmer s'il s'agit d'une espece nouvelle ou d'une variete de C. bardini. Contrairement aux affirmations de Philip et Foster [1971], cette etude met en evidence une forte diversite des marsupiaux ouest-europeens neogenes, comparable a celle des marsupiaux neogenes australiens. Les especes incubantes australiennes et ouest-europeennes sont cependant bien differentes et des similitudes entre ces deux echinofaunes marsupiales n'existent qu'au rang familial. Tant en Australie qu'en Europe nord-occidentale, les especes incubantes appartiennent en effet essentiellement a la famille des Temnopleuridae, avec le genre austral Paradoxechinus, d'une part, les genres nord-europeens Temnotrema et Coptechinus, d'autre part. A noter que les Arbaciidae comptent trois especes incubantes du genre Arbacina en Europe alors qu'aucune espece de cette famille n'est marsupiale en Australie. A l'inverse, plusieurs echinides irreguliers incubants ont ete decrits dans le Cenozoique australien (Spatangoides et Clypeasteroides) alors qu'aucun irregulier muni de marsupium n'a ete decouvert a ce jour dans le Neogene ouest-europeen.

La commune de Tonnay-Charente (Charente-Maritime, Sud-Ouest de la France) comprend de nombreuses exploitations de sables et d'argiles datés de l'Albien terminal et du Cénomanien basal. Ces sédiments se sont déposés dans un contexte côtier où se sont accumulés aussi bien des restes végétaux et de l'ambre que des accumulations de microrestes de vertébrés aquatiques et terrestres. Les deux dernières exploitations à avoir pu être étudiées, Puy-Puy et les Renardières, se sont révélées être des gisements majeurs, la première pour l'abondance et la diversité des méso- et macrorestes végétaux (pollen, cuticules, lignite), notamment des angiospermes, la seconde pour les microrestes de vertébrés, comptant une quarantaine de taxons, dont des sélaciens, des actinoptérygiens, des reptiles divers (crocodiliens, dinosaures, ophidiens, tortues) et un mammifère. Cette note présente les contextes sédimentaires et paléoenvironnementaux des séries albo-cénomaniennes de Puy-Puy et des Renardières et illustre les taxons de vertébrés et de plantes les plus remarquables découverts à ce jour.

Two fragments of a reptile skin have been discovered in the Early Cretaceous (Late Albian) amber of Charente-Maritime (southwestern France). Their systematic attribution is discussed according to the contemporaneous skeleton remains of reptiles discovered in the same region and squamate skin fragments described from other Cretaceous ambers (Lebanon, Myanmar). The preservation of a reptile skin in amber from Charente-Maritime provides further elements for the taphonomic analysis of the amber deposit. To cite this article: V. Perrichot, D. Neraudeau, C. R. Palevol 4 (2005) .

Paleoripiphorus deploegi gen. n., sp. n. and Macrosiagon ebboi sp. n., described from two French Albo-Cenomanian ambers (mid Cretaceous), are the oldest definitely identified representatives of the Ripiphoridae: Ripiphorinae. They belong to or are closely related to extant genera of this coleopteran subfamily. Together with Myodites burmiticus Cockerell, 1917 from the Albian Burmese amber, they demonstrate that the group is distinctly older than suggested by the hitherto available fossil record. By infer- ence after the biology of the extant Ripiphorinae, Macrosiagon ebboi may have been parasitic on wasps and Paleoripiphorus deploegi on bees, suggesting that Apoidea may have been present in the Lower Cretaceous.

Cenomanian beds from western France have yielded a new pythonomorph squamate (Reptilia) that is described here as Carentonosaurus mineaui gen. et sp. nov. This fossil is referred to non-mosasaurid mosasauroid lizards, i.e. to ‘aigialosaurs’. It has been found in sediments of marine origin and its anatomy confirms that it was an aquatic lizard. It is characterized by a combination of characters that has not been reported, thus far, for squamates. Moreover, its vertebral column includes non-pachyostotic cervical vertebrae and highly pachyostotic dorsal vertebrae as in several other ‘aigialosaurs’. This new taxon is perhaps restricted to the upper Cenomanian. It lived in shallow and rather warm water of the inner shelf. It is worth mentioning that nearly all pachyostotic squamates are concentrated in the Cenomanian and/or lower Turonian deposits of the present European-North African-Middle East portion of the Tethys. A parallel is drawn between the high percentage of pachyostotic squamates and the fact that this period corresponds to both the largest transgression of the Phanerozoic and the warmest period in the whole of the Mesozoic and Caenozoic.

A phylogenetic analysis of 36 species provides a test for the taxonomy and the history of Early Cretaceous spatangoids. Most taxonomic units from genera to suborders are consistent with the proposed phylogenetic framework. We retain Hemiasterina, Micrasterina, Hemiasteridae, Schizasteridae, Hemiaster, Heteraster, Mecaster, and Periaster as original monophyletic groups. However, all of these clades originate without the classical apomorphies normally ascribed to them. We suggest a revision of their diagnoses and of the generic attributions of basal species. Some ill-defined, ‘primitive’, and paraphyletic taxa are recognised: Toxaster, Epiaster, Palhemiaster, and Toxasteridae. Even if they do not have phylogenetic meaning, they are retained here, pending a more complete revision.

Resume Le double polymorphisme de R. suborbiculatum au Cenomanien peut se resumer, d’une part, a la presence d’individus partiellement costules et d’individus totalement lisses au sein d’une meme population et, d’autre part, une grande variabilite de taille inter-populationnelle. Apres avoir ecarte tous les assemblages remanies, a partir de l’analyse des frequences de taille, les causes de ces polymorphismes sont analysees d’un point de vue paleoenvironnemental et en terme d’heterochronies du developpement. L’environnement semble, a de rares exceptions, jouer un role mineur dans le controle de ces parametres. Parmi les nombreuses combinaisons existant entre ces deux types de polymorphisme, il est possible d’observer une tendance globale a l’hypermorphose au cours de la transgression cenomano-turonienne. Pour citer cet article : B. Videt, D. Neraudeau, C. R. Palevol 2 (2003).

Resume Un gisement paralique inedit, d’âge Cenomanien inferieur, avec du bois fossile, de l’ambre insectifere et des restes de vertebres, a ete decouvert sur l’estran de la presqu’ile de Fouras (Charente-Maritime, France), a la suite d’une tempete qui a temporairement ote du littoral les nappages de cordons sableux et de vasieres. L’assemblage de bois fossiles contient trois taxons de coniferes ( Agathoxylon , Podocarpoxylon , Brachyoxylon ) et un Ginkgoxylon . Les insectes de l’ambre correspondent a des Dipteres, des Hymenopteres et des Homopteres. Les restes de vertebres sont principalement representes par des carapaces de tortues terrestres (Solemydidae), des vertebres de serpents ( Simoliophis ) et des ossements de dinosaures, appartenant probablement au genre Iguanodon . Pour citer cet article : D. Neraudeau et al., C. R. Palevol 2 (2003).

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