Search

Hundreds of coprolites were found in the Lower Cretaceous locality of Angeac in the Southwest of France, alongside thousands of bones and teeth from dozens of species, encompassing several dinosaurs, crocodilomorphs, turtles and fish (Rozada et al., 2021). Previous studies showed that coprolites can preserve insect remains with great details still intact (Qvarnström et al., 2021). This project focuses on the chemical composition of the coprolites to assess its primary origin and determine the variability between the several morphotypes determined in the locality. First results show that among the major element, Calcium and Phosphorus dominate the relative composition, followed by Iron and Sulphur. For the minor elements, Cerium followed by Yttrium and Strontium present higher concentration in most coprolites. Elementary µXRF maps show that, except for Calcium and Phosphorus, those elements are most of the time more concentrated on the outer rim of the coprolites or in inclusions within. Comparison with surrounding sediments shows coprolites are more enriched of those elements except for Fe and S highly concentrated in pyrite crystals. All those observations strongly suggest a diagenetic origin, by precipitation of fluids inside the coprolites or by conduction with their surfaces. Further work will focus on the analyse of the oxygen isotopic composition of those coprolites. The aim is to assess if the signal is altered or can be used for paleoenvironment and paleoclimatic reconstruction. Such new proxy is very valuable as coprolites could be used instead of teeth and bones when they are not present in the locality or in addition to them to reduce the destruction of skeleton material.

International audience; The terrestrialization process by vertebrates occurred during the Devonian period, with fully land-dwelling tetrapods recorded in the Carboniferous. Thus, the Late Devonian is an important period for deciphering the ecological pressures that applied during the water-to-land transition. Higher predation pressures in the underwater environment have been suggested as an influential biotic evolutionary factor in this key habitat shift. Direct evidence of ancient predation on Palaeozoic vertebrates is seen in the form of rare traces preserved on fossils, and these range from trauma observed on the skeleton (such as attack marks) to ingested food remains (bromalites). The late Famennian freshwater ecosystem of Strud (Belgium) consists of a rich assemblage of many coeval gnathostomes or jawed fishes (placoderms, 'acanthodians', actinopterygians, and various sarcopterygian groups including tetrapods). Here we analyse the record of direct evidence for predation in the Strud vertebrate fossil assemblage. We recognize 12 regurgitalites and 13 bite traces, including a rare case of a tooth embedded in its original prey body target. Fossils from regurgitalites were imaged using scanning electron microscopy and chemically analysed to test for their possible ingestion signature by comparison with other isolated skeletal remains from the same locality. From this evidence, tristichopterid tetrapodomorphs are inferred to be the highest consumers of the trophic network, targeting small placoderms, and porolepiforms, and probably congeners. We observe two possible prey patterns in regurgitalites, for sarcopterygians and actinopterygians, both of which are associated with acanthodians. In Strud, no trophic position can be deduced for tetrapods from direct fossil evidence of predation.

International audience; Les phosphorites du Quercy forment un ensemble de gisements phosphatés ayant livré une importante faune, couvrant la transition Eocène-Oligocène. Au sein de ces gisements, les restes osseux d’amphibiens sont nombreux, bien que majoritairement isolés. En 1873, plusieurs spécimens d’amphibiens et de serpents en furent extraits, présentant une fossilisation assez unique en trois dimensions conservant la forme, les dimensions et l’aspect externe in vivo de ces petits vertébrés. Communément appelés « momies » par leur aspect externe préservé, ces derniers furent décrits au XIXème siècle, sans que leur anatomie interne ne soit en fait connue. Depuis 2012, les spécimens de ces amphibiens commencent à être tomographiés, révélant ainsi la présence interne de tissus mous et squelettiques quasiment complets et articulés. Nous décrivons ici la tomographie d’un deuxième spécimen d’anoure, identifié préalablement comme un « crapaud » (Bufo servatus). Elle révèle la même anatomie que l’autre momie déjà décrite, mais à un stade de développement plus avancé et avec une ceinture pectorale non déformée. Ces individus peuvent être attribués au taxon Thaumastosaurus gezei, et représentent des stades ontogénétiques différents. Avec ces données anatomiques, nous avons inclus Thaumastosaurus au sein d’une phylogénie, le plaçant proche des Pyxicephalidae, clade d’anoures africains. Thaumastosaurus représente à la fois la seule occurrence avérée de ce clade dans le registre fossile et hors d’Afrique. Sa présence en Europe permet par ailleurs de mettre en évidence un échange faunique entre l’Afrique et l’Europe durant l’Eocène. L’émergence de ce type d’herpétofaune africaine en Europe à ce moment serait liée au climat chaud dans la région. Ce taxon et la plus grande partie de cette herpétofaune africaine disparaissent cependant d’Europe lors du refroidissement de la limite Eocène-Oligocène (autour de 34 millions d’années) connu sous le nom de Grande Coupure.

Tardigrades are a diverse group of charismatic microscopic invertebrates that are best known for their ability to survive extreme conditions. Despite their long evolutionary history and global distribution in both aquatic and terrestrial environments, the tardigrade fossil record is exceedingly sparse. Molecular clocks estimate that tardigrades diverged from other panarthropod lineages before the Cambrian, but only two definitive crown-group representatives have been described to date, both from Cretaceous fossil deposits in North America. Here, we report a third fossil tardigrade from Miocene age Dominican amber. Paradoryphoribius chronocaribbeus gen. et sp. nov. is the first unambiguous fossil representative of the diverse superfamily Isohypsibioidea, as well as the first tardigrade fossil described from the Cenozoic. We propose that the patchy tardigrade fossil record can be explained by the preferential preservation of these microinvertebrates as amber inclusions, coupled with the scarcity of fossiliferous amber deposits before the Cretaceous.

Introduction : La notification spontanee des effets indesirables medicamenteux (EIMs) est un des piliers de la surveillance en post-AMM. Une des principales limites de cette derniere concerne la qualite de l’information de ces notifications.L’objectif principal de cette etude etait d’evaluer l’informativite des observations d’EIMs enregistrees dans la Base Nationale de PharmacoVigilance (BNPV) a partir des declarations des medecins generalistes (MGs). L’objectif secondaire etait d’identifier les facteurs associes a une declaration complete.Methode : Toutes les observations d’EIMs declarees en France, en 2015, par les MGs ont ete extraites. Apres analyse du contenu de ces declarations (EIM, date d’apparition, description clinique, medicament impute, etc.), l’informativite etait analysee a partir de plusieurs criteres obligatoires (âge, genre, EIM et medicament(s) suspecte(s)) et facultatifs (antecedents medicaux, medicaments concomitants, evolution de la symptomatologie et examens complementaires) ; cela a permis de classifier les declarations en « bien renseignee », « moyennement renseignee » et « mal renseignee ».Resultats : Durant l’annee 2015, la BNPV comportait 3 020 declarations realisees par les MGs francais. Seulement 16,4 % des declarations de pharmacovigilance rapportees etaient « bien renseignees ». Les criteres les moins bien documentes etaient les medicaments concomitants (41,4 %) et les examens complementaires (37,4 %). Les observations completes etaient associees a la gravite des cas (OR = 3,02 [IC 95 % 2,44 ; 3,23], p

Peracarida (e.g. woodlice and side-swimmers) are, together with their sister-group Eucarida (e.g. krill and decapods), the most speciose group of modern crustaceans, suggested to have appeared as early as the Ordovician. While eucarids' incursion onto land consists of mainly freshwater and littoral grounds, some peracarids have evolved fully terrestrial ground-crawling ecologies, inhabiting even our gardens in temperate regions (e.g. pillbugs and sowbugs). Their fossil record extends back to the Carboniferous and consists mainly of marine occurrences. Here, we provide a complete re-analysis of a fossil arthropod— Oxyuropoda— reported in 1908 from the Late Devonian floodplains of Ireland, and left with unresolved systematic affinities despite a century of attempts at identification. Known from a single specimen preserved in two dimensions, we analysed its anatomy using digital microscopy and multispectral macroimaging to enhance the contrast of morphological structures. The new anatomical characters and completeness of Oxyuropoda , together with a phylogenetic analysis with representatives of all major Eumalacostraca groups, indicate that Oxyuropoda is a crown peracarid, part of a clade including amphipods and isopods. As such, Oxyuropoda is the oldest known species Peracarida, and provides evidence that derived peracarids had an incursion into freshwater and terrestrial environments as early as the Famennian, more than 360 Ma.

In the 19th century, natural mummies of amphibians were discovered in the Quercy Phosphorites. The specific collection site was never formally reported, which hampers precise dating of these specimens. Still, the name Bufo servatus was erected based on the external morphology of one of the mummified specimens. A tomography of a similarly preserved specimen revealed a preserved skeleton, soft tissues and gut contents. We analyze here the holotype of Bufo servatus using CT-scanning in order to investigate its potentially preserved internal features. Like the previous specimen, a subcomplete articulated skeleton was identified in the B. servatus holotype. Surprisingly, this skeleton is almost identical to that of Thaumastosaurus gezei, an Eocene anuran from Western Europe to which other specimens from this mummy series were previously assigned. The few differences between the specimen skeletons highlight ontogenetic and intraspecific variations, making T. gezei a junior synonym of B. servatus and creating the new combination Thaumastosaurus servatus. Given its association with previously described Quercy specimens, this redescribed anuran is probably from the same time interval as T. gezei. Previous phylogenetic analyses assigned T. servatus to Ranoides, with natatanuran affinities. Using data from this newly described specimen, we tested here further its taxonomic affinities. Our analyses confirm this position, and formally identify T. servatus as a Natatanuran member of Pyxicephalidae (currently endemic of equatorial Africa) and more precisely, a stem-Pyxicephalinae. This result confirms the origin of Thaumastosaurus, a member of the African herpetofauna occupying Western Europe before the Grande Coupure at the Eocene/Oligocene transition.

Peracarida (e.g., woodlice & side-swimmers) are, together with their sister-group Eucarida (e.g. krill & decapods), the most speciose group of modern crustaceans, suggested to have appeared as early as the Ordovician. While eucarids incursion onto land consists of mainly freshwater and littoral grounds, some peracarids have evolved fully terrestrial ground-crawling ecologies, inhabiting even our gardens in temperate regions (e.g. pillbugs and sowbugs). Their fossil record extends back to the Carboniferous and consists mainly of marine occurrences. Here, we provide a complete re-analysis of a fossil arthropod – Oxyuropoda – reported in 1908 from the Late Devonian floodplains of Ireland, and left with unresolved systematic affinities despite a century of attempts at identification. Known from a single specimen preserved in two-dimensions, we analysed its anatomy using digital microscopy and multispectral macro-imaging to enhance contrast of morphological structures. The new anatomical characters and completeness of Oxyuropoda, together with a phylogenetic analysis with representatives of all major Eumalacostraca groups, indicate that Oxyuropoda is a crown-peracarid, part of a clade including amphipods and isopods. As such, Oxyuropoda is the oldest known Peracarida, and provides evidence that derived peracarids had an incursion into freshwater and terrestrial environments as early as the Famennian, more than 360 million years ago.

Spontaneous reporting remains one of the cornerstones of post-marketing drug safety surveillance. One of its main limitations is a lack of completeness.The main aim of this study was to assess the completeness of pharmacovigilance reports sent by general practitioners (GPs) to regional pharmacovigilance centers (RPC) reported in the French pharmacovigilance database (FPVD). Secondary aim was to identify factors associated with complete reports.All adverse drugs reactions (ADRs) sent by GPs in France in 2015 were analyzed. According to information provided in ADR reports (ADR, date of occurrence, clinical description, drugs suspected, etc.), completeness was analyzed from#8220;mandatory#8221; criteria (age, gender, ADR#160;and suspected drug(s)) and#8220;non-mandatory#8221; criteria (medical history, concomitant drugs, symptoms evolution and complementary exams) and classified#160;as#160;#8220;well-documented#8221;,#8220;slightly-documented#8221; or#8220;poorly-documented#8221;.In 2015, the FPVD contained 3,020 ADR reports realized by GPs. Only 16.4% of these reports were classified as#8220;well-documented#8221;, in accordance with study criteria. The most poorly documented items were concomitant drugs (41.4%) and complementary exams (37.4%). An association between a#8220;well-documented#8221; ADR report and its#8220;seriousness#8221; (OR = 3,02 [95%#160;CI#160;2,44; 3,23], P#160;lt;#160;10#8211;3) and elderly compared to adults (OR#160;=#160;1,76 [95% CI 1,42; 2,18], P#160;lt;#160;10#8211;3) or children (OR = 4,59 [95% CI 2,51; 8,39], P#160;lt;#160;10#8211;3).Our study shows that only one out of six ADR reports was#8220;well-documented#8221;. It appears to be important to promote pharmacovigilance to improve completeness of ADR reports.

Isopod crustaceans have developed a variety of feeding strategies, which impact on their various life habits over time. Apart from morphological adaptations and the typical secondary deformations that some parasitic isopods inflict on their host's exoskeleton, traces of feeding behaviours involving isopods on their victim/food are seldom fossilized. Many of these rare occurrences consist of cases for which the degree of association between the isopods and their potential food source is unclear, or the interaction only very briefly explained (recently analysed cases excepted). There are two limiting problems in identifying the biological nature of fossilized associations: (1) direct associations of organisms preserved as ‘imprint’ (as opposed to inclusions in cherts or amber) are shaped by several taphonomic events difficult to identify (such as the time of death, burial and fossilization of the organism); (2) even in modern nature, differences within syn vivo interactions (like parasitism and micropredation) are poorly understood in marine systems. We report the occurrence of isopods associated with ancient chondrichthyans which also represent rare cases of the preservation of several fossil isopods on larger organisms. These organisms are adult electric rays of the genus †Titanonarke Carvalho from the late Ypresian (Eocene) of the Monte Postale site, Bolca Lagerstätte, Italy. By examining: (1) the involved lineages of rays and isopods; (2) the taphonomy of the association; (3) its environmental context; and (4) biological/adaptive features; we identify this association as a selective case, either of ancient scavenging or of micropredation on specific electric rays by isopods.

Epibionts are uniquely valuable in their ability to constrain paleoecological hypotheses about their own as well as their host's behavior and environment. Rarely preserved epizoic bryozoans are here reported on fossil crabs from the Miocene Mishan Formation in the Zagros Basin of southwestern Iran. One-hundred-thirty-eight decapod crustaceans were recovered from the upper marly member of the Mishan Formation. Of those, seven decapods (5%) were fouled by bryozoans. Of these seven decapods, five had bryozoans growing attached to the cuticle of the hard outer surface of the exoskeleton of the host crabs and thus fouled while the host crab was potentially alive. Forty percent of the bryozoan colonies occurred on the host crab's dorsal carapace, and 60% were found on chelipeds. On average, 30% of the surface area of the host crabs' fouled skeletal components were covered by bryozoan colonies. The brachyurans were mostly leucosiids, including Leucosia persica and Myra sp. The bryozoans were all cheilostomes and included Acanthodesia sp., Thalamoporella sp., and an indeterminate ascophoran. These bryozoans are all the first reported occurrences in the Mishan Formation. The low incidence of crabs fouled by bryozoans is attributed to preservational bias. The results from this study are compared to those of fossil and extant host crabs reported in the literature. The bryozoan-crab relationship documented here is best described as commensalism.

With approximately 1,500 extant species, freshwater crabs (Decapoda: Brachyura) are among the most diverse decapod crustaceans. Nevertheless, their fossil record is extremely limited: only Potamidae, Potamonautidae and Trichodactylidae are reported up to the Eocene of the Neotropics so far. This work documents unusually large decapod claws from the Upper Cretaceous (Campanian) continental deposits of Velaux and vicinity (southern France), in close association with large vertebrate remains. In addition to (1) the systematic assignment of these claws, the study addresses (2) the salinity trends in the deposit environment from its faunal assemblage and the elementary chemical patterns of fossils, and (3) the likely scenario for their auto/allochthony in the Velaux fluvial system. These claws belong to a new taxon, Dinocarcinus velauciensis n. gen. n. sp., referred to as Portunoidea sensu lato, a group of “true” crabs nowadays linked to marine systems. However, the faunal assemblage, the claw taphonomy and the carbonates Y/Ho signatures support their ancient freshwater/terrestrial ecology, making them the oldest reported continental brachyurans and extending the presence of crabs in freshwater environments by 40 Ma. Either as primary or as secondary freshwater crabs, the occurrence of these portunoids in Velaux is an evidence for the independent colonizations of continental environments by multiple brachyuran clades over time, as early as the Campanian.

Exceptional and extremely rare preservation of soft parts, eyes, or syn-vivo associations provide crucial palaeoecological information on fossil-rich deposits. Here we present exceptionally preserved specimens of the polychelidan lobster Voulteryon parvulus, from the Jurassic of La Voulte-sur-Rhône Fossil-Lagerstätte, France, bearing eyes with hexagonal and square facets, ovaries, and a unique association with epibiont thecideoid brachiopods, giving insights onto the palaeoenvironment of this Lagerstätte. The eyes, mostly covered in hexagonal facets are interpreted as either apposition eyes (poorly adapted to low-light environment) or, less likely, as refractive or parabolic superposition eyes (compatible with dysphotic palaeoenvironments). The interpretation that V. parvulus had apposition eyes suggests an allochthonous, shallow water origin. However, the presence of thecideoid brachiopod ectosymbionts on its carapace, usually associated to dim-light paleoenvironments and/or rock crevices, suggests that V. parvulus lived in a dim-light setting. This would support the less parsimonious interpretation that V. parvulus had superposition eyes. If we accept the hypothesis that V. parvulus had apposition eyes, since the La Voulte palaeoenvironment is considered deep water and had a soft substrate, V. parvulus could have moved into the La Voulte Lagerstätte setting. If this is the case, La Voulte biota would record a combination of multiple palaeoenvironments.

Thousands of silicified wood fragments were recently collected from the middle Cenomanian of Vienne in western France at less than 10 km away from a historical locality where in 1870 the French geologist Alphonse Le Touzé de Longuemar reported silicified wood. The plant assemblage is very diverse, and includes several species of ferns, conifers, and angiosperms. We describe and discuss the systematic affinities of a new vesselless angiosperm. Many of its characters are shared by extant and fossil Winteraceae. Nevertheless, the absence of uniseriate rays makes the anatomy of these specimens unique. Its combination of characters justifies the establishment of a new genus of vesselless fossil angiosperm wood of uncertain affinity, Sherwinoxylon gen. nov.

Newly collected decapod material from the Cap de Naze Formation (middle–upper Maastrichtian), Senegal, allows description of a new species of Costacopluma (Brachyura: Retroplumidae), which is older than Costacopluma senegalensis (Remy in Gorodiski & Remy, 1959) from the Paleocene of Senegal and documents that the genus survived the end Cretaceous event in the same area. The holotype of Costacopluma mamethioupamei n. sp. is preserved both in dorsal and ventral aspects, and it bears a strange dumbbell-shaped “scar” on sternite 4 which is tentatively interpreted as a true epibiont mark or remain, which encrusted the crab cuticle syn-vivo or post-mortem; the identification of the tracemaker is obscured. The cuticular microstructure of Costacopluma mamethioupamei n. sp. is documented using SEM imaging. The cuticle appears to be preserved in its entirety and areas with damaged cuticle shows several distinct layers interpreted as endocuticle, exocuticle and epicuticle. Thanks to the present report of Costacopluma mamethioupamei n. sp. it is now clear that the genus survived the K/Pg boundary not only in the area of the Gulf of Mexico (as documented by several previously published reports) but also in the present-day Senegal. From the palaeobiogeographic perspective, it is interesting to note, that the African continent has been inhabited only with narrow-ridged species of Costacopluma, including Costacopluma concava Collins & Morris, 1975, C. senegalensis and C. mamethioupamei n. sp. This lineage may finally lead to the origin of Tethyan retroplumids, which were widely distributed across Europe during the Eocene.

International audience; Teredinidae are obligate xylophagous bivalves that colonize drift wood. They display a highly derived anatomy with a reduced shell; most of their body consists of soft tissues. Consequently, fossil teredinids mostly correspond to burrows, shells or small terminal aragonite structures called ‘pallets’. We report, from mid‐Cretaceous logs of the Envigne Valley, France, exceptionally preserved wood‐boring bivalves with silicified soft parts. After characterizing the wood, we report both the molluscs’ anatomy and their distribution inside the wood (using computed tomography). The 3D‐reconstructions reveal rarely preserved soft tissues (mantle, respiratory siphons, visceral pouch) but surprisingly no mineralized pallets. Envigne shipworms display neat dorsal condyles and a vermiform body plan, making them the oldest known Teredinidae. To document the evolutionary or taphonomic origin of this lack of pallet, the mineralization of these bivalves was investigated, and it is concluded that pallets could have dissolved prior to other carbonate components. From a survey of the fossil wood‐boring bivalves and their characters, we provide a time scaled origin of the main pholadoid clades supported in recent phylogenies. Since we found no correlation between the presence of pallets in Pholadoidea and their occurrence in the stratigraphic record, we suggest that their absence during the Mesozoic could be the result of a taphonomic bias related to the ‘calcite vs aragonite seas’ paradigm. The Cenomanian Envigne Valley was an estuarine to intertidal environment in which the Teredinidae appear to have selected their wood habitat on the basis of size but not type.

International audience; Softwoods constitute an important part of the plant macro-remains that are found within the Carboniferous to the most recent fossil deposits. Their taxonomical study is mostly made possible thanks to classical references (Philips 1948, Greguss 1955, Esteban 2004, Philippe & Bamford 2008). As for hardwoods, in addition to similar standard publications, a dedicated database has started being developed seven years ago (Insidewood - Wheeler 2011). Today Insidewood constitutes a very useful and indispensable tool, in constant development, which allows online identification for extant and fossil hardwoods. Despite their abundance in fossil deposits, no tool dedicated to softwoods has been developed yet. To fill this gap, we initiated the implementation of a softwood database, ABIeS, on the biodiversity collaborative management platform Xper3 (Ung et al. 2010). The descriptive model is mainly based on IAWA list of softwood features (IAWA committee 2004) but we also propose original features linked for instance to cell size and cross-field characteristics. As a first step, we tried as much as possible to illustrate the softwoods diversity using local resources. Therefore, extant species were chosen among the one hosted at the MNHN-xylarium, Paris, whereas fossil species where chosen from the collection Boureau (UPMC, Paris). We finally carried a global analysis of the database in order to better understand the softwood variability regarding systematics and ecology. This project, although initiated in our laboratory in Paris has a collaborative aim. We invite all the researchers who are interested by the wood anatomy of extant and fossil conifers to join us. Esteban, L. G., de Palacios, P. D. P., Casasús, A. G., & Fernández, F. G. (2004). Characterisation of the xylem of 352 conifers. Forest Systems, 13(3): 452-478.Greguss, P. (1955). Identification of living gymnosperms on the basis of xylotomy. Akademiai Kiado, Budapest. 263 pp.IAWA committee (2004). IAWA list of microscopic features for softwood identification. IAWA J, 25(1): 1-70.Philippe, M., & Bamford, M. K. (2008). A key to morphogenera used for Mesozoic conifer-like woods. Review of Palaeobotany and Palynology, 148(2-4): 184-207.Phillips, E.W.J. 1948. Identification of Softwoods. Forest Products Research Bulletin 22, 56 p.Ung, V., Dubus, G., Zaragüeta-Bagils, R., Vignes-Lebbe, R. 2010. Xper2: introducing e-taxonomy. Bioinformatics, 26 (5): 703-704.Wheeler, E.A. (2011). InsideWood - a web resource for hardwood anatomy. IAWA J. 32 (2): 199-211.

Kerguelen Islands are predominantly volcanic lands, thus fossil references are very uncommon. However, its Miocene fossils are of specific interest for understanding migration routes of some taxa during the Cenozoic, given the intermediary position of Kerguelen with various continents. Despite this fossil rarity, we studied herein hundreds of nodules corresponding to the sole known fossil brachyurans (and unique Decapoda) from Kerguelen both for their systematics and their preservation. Indeed, these crabs display some internal fragile structures that are rarely fossilized, such as the gills’ branchial lamellae, preserved in volume. The preservation of these gills and their diagenetic features were documented through traditional imagery (SEM), including morphological comparison to modern gills, and with petrographic and geochemical analyses (EDS, X-ray diffractometry). Some cheilostome bryozoans were observed as probable foulers of the crabs carcasses. The fossil material corresponds to a new cancrid crab (Romaleon franciscaen. sp.) and its occurrence may imply a novel route from South America westward for the geographic migration of the genusRomaleon, since its Cretaceous emergence. The cup-shape and the number and the organization of the gills in these fossil Cancridae specimens are similar to those observed in their extant representatives. Gill preservation in 3D is linked to very early phosphatization of the system during diagenesis, as shown by the nodule matrix, and likely to deposition of a thin clayey cover on the soft-tissues. The implication of intrinsic phosphorous in the differential phosphatization of the crabs’ anatomy remains difficult to determine.

Using microscopy and spectroscopy tools, we succeeded in identifying undescribed diminutive epibionts (as epibiotic bacterial colonies) both on exceptionally well-preserved fossil shrimps and on extant taxa (N. Robin, S. Bernard, J. Miot, M.-M. Blanc-Valleron, S. Charbonnier & G. Petit, submitted). This study outlines the ecological parameters of this totally newly recognized interspecific association. To this aim, the systematics and environmental setting of fossil and modern decapod hosts are described; count of bacterial colonies is made to assess prevalence and intensity; scanning electron microscopy is used to illustrate colonial growth patterns; and histological sections of the extant colonies nested in cuticle are stained to determine their incidence on the carapace of their decapod hosts. Thus, the prevalent and intense association is found on decapods of the superfamily Penaeoidea Rafinesque-Schmaltz 1815 occupying up to 2 cm2 of the entire carapace. The association is here observed in deep environments such as that of the Jurassic La Voulte-sur-Rhone Lagerstatte. A non-random distribution of colonial growth patterns is determined; it illustrates a favourite access site along the ventral margin of the shrimp carapace. SEM images and stained sections reveal strong colony embedment within the cuticle, but also damage such as erasing of the cuticular layers. This bioeroding effect, possibly linked to a feeding benefit to the bacteria, brings this interspecific association that has existed, for at least 160 myr, near to parasitism. In addition to illustrating a rare case of interaction in Recent forms that could be described due to previous recognition in fossils, it constitutes a textbook example of the preservation of intimate interactions through geological time.

Symbioses such as mutualism, commensalism and parasitism are crucial factors for evolutionary strategies and innovations. Epibiotic associations are particularly difficult to detect in the fossil record and, only exceptionally preserved organisms from Konservat-Lagerstatten, may provide new data to reveal past symbioses. Microscopic epibionts are here described on a small erymid lobster (Crustacea, Decapoda) from the Upper Jurassic Eichstatt Lagerstatte, Germany. These epibionts are here identified as nubeculariids, a group of foraminifera encrusting inorganic substrates or sometimes sessile organisms. This is the first report of nubeculariids fixed on a mobile host both in the fossil and extant records. The relevance of this association in the paleoenvironmental context is discussed to argue the possible symbiotic feature of this partnership. Next, the benefits and costs for both partners are assessed to finally deduce that a phoretic relation could have existed between nubeculariids and decapod crustaceans during the Late Jurassic.

Coprolites of terrestrial vertebrates from the Sparnacian Le Quesnoy locality (Ypresian, Eocene, MP7, 53 Ma; Oise, France) were examined for possible parasitic helminth eggs. The extraction of the coprolite components was performed by a weak acetolyse and a slide mounting in glycerin. This long examination did not reveal paleoparasite remains, which may be explained through several arguments. However, some pollen grains, some enigmatic components, and two well-preserved first-instar cochineal nymphs (Hemiptera: Sternorrhyncha: Coccoidea) were evidenced in coprolites. Identified as Coccidae, these larvae are the earliest stage of the scale insect development ever reported as fossil, revealing the specific environment of preservation that fossilized scats may provide. These observations, combined to the coprolites morphotype, enable to ascribe the fossil scats producer to a small herbivorous mammal present in the deposit (early perissodactyls or Plesiadapidae). Regarding the ecology of extant representatives of Coccidae, this mammal was a likely foliage consumer, and the abundant Juglandaceae and/or Tiliaceae from Le Quesnoy might have lived parasitized by scale insects. These Early Eocene parasites had an already well-established dissemination strategy, with prevalent minute first-instar larvae. The herein performed extraction technique appears well-suited for the study of carbonate coprolites and could certainly be useful for evidencing other kind of microorganisms (including internal parasites).

Fossil symbioses (Bary 1879) that are not recognized in modern assemblages are rare. This holds true especially because fossil remains of interspecific association are sporadic and difficult to document. Thus, fossil associations illustrated on a large number of specimens are of particular interest. Numerous specimens of mecochirid lobsters (Glypheidea, Decapoda, Crustacea) from the Lower Cretaceous of the Atherfield Clay Formation (Isle of Wight, UK) seer small epibiotic bivalves on their exoskeleton. We propose to identify the post-mortem or syn-vivo nature of this association. To this end, we test and revise the systematic assignment of both crustacean and molluscan partners. A new genus name is proposed for the crustacean Meyeria magna M'Coy, 1849, as well as the new combination Atherfieldastacus magnus (M'Coy, 1849). To understand the nature of the association, a qualitative and quantitative study of the association is conducted on newly examined material (161 lobsters) looking at prevalence, density and abundance of the infestation (per anatomical region of the lobsters). Angularities and flat surface of exoskeletons were also evaluated. The distribution of the bivalves on both sides of the crustaceans (60% of the colonized lobsters), their preservation and their downward growth orientation suggests no post-mortem attachment of the mollusks. Hence, the association may be ascribed to a true palaeosymbiosis between these organisms. The non-homogeneous distribution of bivalves, that is to say an important colonization of the angular ridges of the carapace, is interpreted as selected sites by the mollusks for larval fixation, and may indicate possible half-burrowing posture of lobsters. This palaeosymbiosis has no modern equivalent, as cemented bivalve shells have never been reported on any population of decapod crustaceans. This fossil association may be ascribed to a local Aptian palaeoenvironment comprising swarming spats of anomiid bivalves.

As the lowermost stage of the Palaeogene, the Danian is a key period for ecosystems which followed the K–Pg boundary. The Vigny quarry (Val d'Oise, France) is a co-stratotype of the Danian stage, along with the well-known one of Fakse (Denmark). The Vigny ecosystem (Bois-des-Roches site at Vigny and allied Danian localities) is the only known Cenozoic reef of the Paris Basin and is formed by hermatypic corals, unlike reefs at Fakse. Well studied by scientists, including d'Orbigny, for almost two centuries, the decapod crustacean fauna of Vigny has been much less documented than that of Fakse. Here, we describe new material of decapod crustaceans from the Danian of the Paris Basin, based on material in the Muséum national d'Histoire naturelle (Paris). This material (six carapaces and 14 isolated claws) constitutes anomurans, brachyurans and, for the first time, axiideans in the Danian of the Paris Basin. Among brachyurans, it includes the paleoxanthopsid crab Jakobsenius cretaceus is described and the dynomenid Dromiopsis mosae. Two new brachyuran species are described from Vigny: Titanocarcinus schweitzerae sp. nov. (Tumidocarcinidae) and Dromilites montenati sp. nov. (Dromiidae). The latter is the oldest representative of its genus. The Danian decapod crustaceans of the Paris Basin are revised and their diversity is compared to that at Fakse. The enigmatic association of a limpet (Patella herbetiana) attached to a crab carapace is described and interpreted. Based on a small number of available specimens, this study reveals some specificity of the Vigny brachyuran fauna and recognizes the Paris Basin as an important region for knowledge of Danian decapod crustaceans. http://zoobank.org/urn:lsid:zoobank.org:pub:2813A14B-AE65-4296-9C3C-2B10B9C5DC6B

Symbiosis [1], understood as prolonged interspecific association, is as ancient as the eukaryotic cell [2, 3]. A variety of such associations have been reported in the continental fossil record, albeit sporadically. As for mites, which as a group have been present since the Devonian (ca. 390 mya) [4, 5] and are involved in a tremendous variety of modern-day symbioses, reported associations are limited to a few amber-preserved cases [6-11], with the earliest instance in the Cretaceous (ca. 85 mya) [11]. As a consequence, the antiquity and origin of associations involving small-sized mites and larger animals are poorly understood. Here we report, recovered from the Carboniferous Xiaheyan locality (ca. 320 mya), an oribatid mite located on the thorax of an extinct relative of grasshoppers, crickets, and katydids [12]. The mite was investigated using several methods, including phase-contrast tomography. The detailed morphological data allowed the placement of the mite in a new family within Mixonomata, whose fossil record is thus extended by ca. 250 Ma. Specimen and abundance distribution data derived from the fossil insect sample indicate that specimens from the corresponding excavation site were buried rapidly and were sub-autochthonous, indicating a syn vivo association. Moreover, the mite is located in a sequestered position on the insect. The observed interaction best fits the definition for phoresy, in which the benefit is transport and protection for the mite. This discovery demonstrates that this association, a trait shared by representatives of the most speciose mite taxa, arose very early during mite evolution.

International audience; Evidencing ancient interspecific associations in the fossil record may be challenging, particularly when bacterial organisms have most likely been degraded during diagenesis. Yet, documenting ancient interspecific associations may provide valuable insights into paleoenvironmental conditions and paleocommunities. Here, we report the multiscale characterization of contemporary and fossilized calcifying bacterial colonies found on contemporary shrimps from Mexico (La Paz Bay) and on 160-Ma old fossilized decapods (shrimps) from the Lagerstätte of La Voulte-sur-Rhône (France), respectively. We document the fine scale morphology, the inorganic composition and the organic signatures of both the contemporary and fossilized structures formed by these bacterial colonies using a combination of electron microscopies and synchrotron-based scanning transmission X-ray microscopy. In addition to discussing the mechanisms of carbonate precipitation by such bacterial colonies, the present study illustrates the degradation of bacterial remains occurring during diagenesis.

The earliest known crabs are of Early and Middle Jurassic age; in general, they are rare. Here we describe a new species of homolodromioid from the late Bathonian of Sarthe (France), based on a single dorsal carapace, Tanidromites raboeufi n. sp. This specimen has mostly well-preserved cuticle, and shows two episkeletozoans (bryozoan colonies) on its dorsal side, which is unique amongst early brachyurans (Early and Middle Jurassic). These bryozoans are identified as juvenile colonies of the morphogenus Berenicea (sheet-like tubuluporines), typical encrusters of hard substrates. Their presence directly on the carapace crab shows that they were closely cohabitating with this early brachyuran in its palaeoenvironment. One of these colonies appears to have attached to the internal carapace surface, indicative of post-mortem settlement and growth. Colony sizes suggest a growth phase of at least several months on the sea floor, implying a certain resistance to decomposition of the crab carapace. This is of note in the light of extant homolodromioids which are known to have extremely fragile carapaces. This association demonstrates that post-mortem associations may yield palaeoecological insights into both substrate and colonising organisms.