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International audience; The genus Uranotaenia (Diptera: Culicidae) has been well documented in Madagascar where it includes 73 species, 89.4% being endemic. However, one problem is that most species are morphologically similar in the adult stage. Here, 713 Uranotaenia specimens collected in the tropical forests of Anorana and Maromizaha between 2008 and 2014 were examined. Using the dichotomous keys for the Uranotaenia fauna of Madagascar published in 2004, three species were identified: Uranotaenia neireti (220), Ur. alboabdominalis (110) and Ur. mayottensis (28). The other specimens (355) were not identifiable and were classified as Uranotaenia sp1. Using wing morphometry, the four taxa were classified into four morphogroups. Within the Uranotaenia sp1 group, specimens from the Anorana forest and those from the Maromizaha forest overlapped. This result suggests that wing morphometric traits could be a good marker to distinguish Uranotaenia species in Madagascar.

International audience; Polychelidan lobsters are decapod crustaceans characterized by their four to five pairs of claws. The first description of a polychelidan lobster dates back to 1817, and since then, numerous species have been described with varying level of details. This situation sometimes led to the description of synonymous species, and more generally, led to a lack of overview on the group systematic and evolutionary history. Herein, we review Proeryon¸ one of the most diversified and stratigraphically widespread polychelidan. We argue that Proeryon is closely allied to Tethyseryon and Gabaleryon and propose to assign them to Proeryoninae nov. subfam., which are mainly characterized by their hemicircular ocular incision, postorbital and branchial carinae not joined together, and axial carina on pleonites cut by transverse grooves. Proeryon is in turn characterized by its marked cervical and hepatic incisions, simple posterolateral spines and arched uropodal exopod diaeresis. Thus defined, we assign the following species to Proeryon: P. charbonnieri, P. giganteus, P. hauffi, P. laticaudatus, P. richardsoni, P. stoddarti and two unnamed species from the Hauterivian of Germany and Switzerland, respectively. In addition, we refer to Proeryon, with some reservations, two new species,?Proeryon quiltyi from the Callovian of Antarctica and?Proeryon erinaceus from the Oxfordian of France. Proeryon has highly discontinuous but large stratigraphic (Pliensbachian – Hauterivian: about 60 MA) and palaeogeographic (from United Kingdom to Siberia, and to Antarctica) distribution. Most of these species occurs in relatively deep neritic or deeper palaeoenvironments. It is possible that this deep-sea dwelling is one of the reasons why Proeryon survived so long. Also, we note the presence of abundant oysters living as epibionts on some specimens of Proeryon hartmanni. Their disposition and number suggest that P. hartmanni was an epibenthic animal.; Les Polychelida sont des crustacés décapodes caractérisés par la présence de quatre à cinq paires de pinces. La première espèce de Polychelida a été décrite en 1817 ; depuis, de nombreuses espèces ont été décrites avec plus ou moins de détails. Cette hétérogénéité a abouti à la description de nombreuses espèces synonymes, limitant notre compréhension de la systématique et de l’évolution des Polychelida. Dans cet article, nous réétudions Proeryon, l’un des genres de Polychelida les plus diversifiés et possédant une grande répartition stratigraphique. Proeryon semble proche de Tethyseryon et Gabaleryon ; nous proposons donc de réunir ces trois genres au sein des Proeryoninae nov. subfam., caractérisés par une incision oculaire hémicirculaire, une carène postorbitaire distincte de la carène branchiale et la carène axiale des pléonites recoupée par les sillons transversaux. Proeryon se distingue par ses incisions cervicales et hépatiques marquées, ses épines postérolatérales simples et sa diérèse arquée sur l’exopode de l’uropode. Ainsi, nous incluons dans Proeryon les espèces suivantes : P. charbonnieri, P. giganteus, P. hauffi, P. laticaudatus, P. richardsoni, P. stoddarti et deux espèces de l’Hauterivien d’Allemagne et de Suisse restées en nomenclature ouverte. De plus, nous suggérons que ?Proeryon quiltyi du Callovien d’Antarctique et?Proeryon erinaceus de l’Oxfordien de France sont également des Proeryon. La répartition stratigraphique (Plienbachien-Hauterivien) et paléogéographique (du Royaume Uni à la Sibérie) de Proeryon est très étendue mais également extrêmement discontinue. La plupart des espèces de Proeryon proviennent de paléoenvironnements néritiques assez profonds. Il est imaginable que la vie en milieux profonds soit une des raisons expliquant comment Proeryon a survécu si longtemps. D’autre part, nous notons d’abondantes huîtres vivant en épibiontes sur certains spécimens de Proeryon hartmanni. Leur disposition et abondance suggèrent que P. hartmanni était un animal épibenthique.

International audience

International audience; The horizontal and vertical distribution of mosquito species was studied in Maromizaha rainforest, Madagascar. In November 2014, horizontal distribution was studied using light traps that were placed in four habitat types, ranging from degraded forest to primary rainforest. In November to December 2016, vertical distribution was studied using light traps placed near to the ground and elevated near the canopy. From the horizontal survey, 476 adults were collected: Uranotaenia (52.10%) and Culex (35.2%) were the most abundant genera. The highest numbers of mosquitoes were observed in the rainforest edge habitat, while the highest mosquito diversity was observed within primary rainforest. From the vertical survey, 276 adults were collected: Culex was the most abundant genus and represented 75.70% of adults caught. Mosquitoes were more abundant in traps placed near the ground than those near the canopy. The highest species diversity was observed near the canopy. The higher abundance of mosquitoes at the forest edge agrees with the role of this zone as an ecotone between intact rainforest and the nearest human habitation. Increased mosquito abundance in lower strata might heighten their contact with particular vertebrate hosts. The presence of vectors in different habitats and in varying elevations likely influences the risk of pathogen transmission between animals and humans in this rainforest.

This work received support from the CERCA programme (ICP) from the Generalitat de Catalunya. Newly discovered tetrapod footprints from the middle Permian Pelitic Formation of Gonfaron (Le Luc Basin, Var, France) are described in detail and assigned to the ichnogenus Hyloidichnus. These specimens are very well-preserved, with detailed trackways showing anatomical features, digit drag traces and continuous tail impressions. Together with other Hyloidichnus specimens from the same locality and from the University of Burgundy collections, they allow the identification of the possible trackmakers of Hyloidichnus: small Hyloidichnus footprints are correlated with captorhinomorphs with autopodia similar to Captorhinus whereas large Hyloidichnus footprints might be correlated with larger captorhinomorphs or other 'basal' (eventually stem-) moradisaurines. A detailed comparative analysis is proposed to better understand the locomotion style of the trackmakers. Starting from the reconstruction of the stance phase of Captorhinus, we document the swing phase of the fore- and hind-limbs of captorhinomorphs thanks to the continuous digit drag traces associated with Hyloidichnus. A link between gait and track preservation have been highlighted through the analysis of tail impressions and high-resolution 3D models. In all, this study increases our understanding of captorhinomorph locomotion and enhances the integration of both tracks and skeletal remains to highlight the biomechanics of Permian tetrapods.

International audience; Plusieurs spécimens fossiles d’arthropodes marins inédits, conservés au Muséum national d’Histoire naturelle à Paris (France) et provenant des Calcaires lithographiques de Solnhofen et de Nusplingen (Jurassique supérieur, Allemagne), sont décrits et illustrés. Nous décrivons notamment des spécimens d’Antrimpos undenarius Schweigert, 2001, d’Eryma modestiforme (Schlotheim, 1822) et de Mecochirus longimanatus (Schlotheim, 1820). Mecochirus foresti Secrétan, 1968 est considéré comme un synonyme plus récent de Mecochirus longimanatus. Une révision des spécimens décrits précédemment est également réalisée. Cet article fournit ainsi de nouvelles informations sur les espèces d’Antrimpos présentes dans les Plattenkalks de Solnhofen et donne un aperçu complet des arthropodes marins fossiles provenant de ces localités et disponibles au MNHN.

Paola Movalli et al., European Raptor Biomonitoring Facility COST Action (CA16224) is supported by COST (European Cooperation in Science and Technology) and funded by the Horizon 2020 Framework Programme of the European Union. Life APEX is financed by the European Union through the program LIFE17ENV/SK/000355‘Systematic use ofcontaminant data from apex predators and their prey in chemicals management’.

International audience; An annotated checklist of the fish species of the Madagascar EEZ (southwestern Indian Ocean) comprises a total of 1,798 species in 247 families. 158 species are recorded from Madagascar for the first time. The majority of the species is autochthonous; 28 species have been introduced, mainly in freshwater habitats. The fish fauna is mostly marine (95.4% of the total number of native fish species), with the Gobiidae, Labridae, Serranidae, Pomacentridae and Apogonidae being the families with most representatives; among the 90 native freshwater fish species (adults mainly occurring in freshwater), the Cichlidae are the dominating family, but there are also two endemic families, the Bedotiidae (16 species) and Anchariidae (6 species). The fish fauna at Madagascar is typical for offshore, high islands in the southwestern Indian Ocean. Zoogeographically, the main element of the marine fish fauna of Madagascar consists of widespread tropical Indo-Pacific species (978 species, 58.3% of the total native marine species). A total of 13 species (3.3%) are found worldwide, either circumtropical or circumtropical including warm temperate zones. A total of 215 species (12.8%) are found worldwide, either circumtropical or circumtropical including warm temperate zones. An additional 453 species (27.0%) are Indian Ocean endemics, including 233 western Indian Ocean endemics (13.9%), 73 southwestern Indian Ocean endemics (4.4%), 16 species endemic to Madagascar and Mascarenes (1.0%), 4 species endemic to Madagascar and Comoros (0.2%), 3 species endemic to Madagascar and Madagascar Ridge(0.2%), and 37 marine species endemic to Madagascar (2.2%). Most of the autochthonous freshwater fishes are endemic to Madagascar (87 species, 96.7% of the native freshwater species).

International audience; With 280 accepted species, the genus Riccardia S.F.Gray (Aneuraceae) is one of the most speciose genera of simple thalloid liverworts. The current classification of this genus is based on morphological and limited-sampling molecular studies. Very few molecular data are available and a comprehensive view of evolutionary relationships within the genus is still lacking. A phylogeny focusing on relationships within the large genus Riccardia has not been conducted. Here we propose the first worldwide molecular phylogeny of the genus Riccardia, based on Bayesian inference and parsimony ratchet analyses of sequences from three plastid regions (psbA-trnH, rps4, trnL-F). The results support the monophyly of Riccardia and a new monospecific genus, Afroriccardia Reeb & Gradst. gen. nov., is described based on molecular and morphological evidence. The results indicate that several currently recognized infrageneric divisions and a few species are not monophyletic, suggesting that further analyses are needed to arrive at a proper understanding of the phylogeny of the genus. Although evidence for an Andean clade was found, most of the species appear scattered in different clades without clear geographical segregation. Broader sampling and further analyses are necessary in order to improve our understanding of the phylogeny of this poorly known liverwort genus.

International audience; BACKGROUND:Avian malaria occurs almost worldwide and is caused by Haemosporida parasites (Plasmodium, Haemoproteus and Leucocytozoon). Vectors such as mosquitoes, hippoboscid flies or biting midges are required for the transmission of these parasites. There are few studies about avian malaria parasites on Madagascar but none about suitable vectors.METHODS:To identify vectors of avian Plasmodium parasites on Madagascar, we examined head, thorax and abdomen of 418 mosquitoes from at least 18 species using a nested PCR method to amplify a 524 bp fragment of the haemosporidian mitochondrial cytochrome b gene. Sequences obtained were then compared with a large dataset of haemosporidian sequences detected in 45 different bird species (n = 686) from the same area in the Maromizaha rainforest.RESULTS:Twenty-one mosquitoes tested positive for avian malaria parasites. Haemoproteus DNA was found in nine mosquitoes (2.15%) while Plasmodium DNA was found in 12 mosquitoes (2.87%). Seven distinct lineages were identified among the Plasmodium DNA samples. Some lineages were also found in the examined bird samples: Plasmodium sp. WA46 (EU810628.1) in the Madagascar bulbul, Plasmodium sp. mosquito 132 (AB308050.1) in 15 bird species belonging to eight families, Plasmodium sp. PV12 (GQ150194.1) in eleven bird species belonging to eight families and Plasmodium sp. P31 (DQ839060.1) was found in three weaver bird species.CONCLUSION:This study provides the first insight into avian malaria transmission in the Maromizaha rainforest in eastern Madagascar. Five Haemoproteus lineages and seven Plasmodium lineages were detected in the examined mosquitoes. Complete life-cycles for the specialist lineages WA46 and P31 and for the generalist lineages mosquito132 and PV12 of Plasmodium are proposed. In addition, we have identified for the first time Anopheles mascarensis and Uranotaenia spp. as vectors for avian malaria and offer the first description of vector mosquitoes for avian malaria in Madagascar.

International audience; Polychelidan lobsters are decapod crustaceans with a unique anatomy: a dorsoventrally flattened carapace, four to five pairs of chelate appendages and a completely reduced rostrum. These crustaceans, like most other malacostracans, are mostly preserved in outcrops in which exceptional preservation occurs, Fossil-Konservat-Lagerstätten. Unfortunately, Lagerstätten are rare, and therefore disjointed both geographically and stratigraphically. This study focuses on a new genus of polychelidan lobster, Gabaleryon gen. nov., with the description of two new Toarcian species, Gabaleryon coquelae sp. nov. from France and G. garassinoi sp. nov. from Italy. The long-standing question of the generic assignment of Eryon moorei (Toarcian, UK) is resolved and the species is ascribed to Gabaleryon. The occurrences of these three species and a fourth, Gabaleryon sp. 1 (Toarcian, Germany), provide a first palaeobiogeographical indication that the Fossil-Lagerstätten in which they occur were linked during Toarcian times. The occurrence of a possible fifth species of Gabaleryon in the late Bajocian–early Bathonian of France may extend the stratigraphical distribution of the new genus. Finally, these new species increase our knowledge of fossil polychelidans and place the Toarcian as their second peak of palaeobiodiversity, after that at the Kimmeridgian–Tithonian boundary. http://zoobank.org/urn:lsid:zoobank.org:pub:073513BD-A0D8-4A5B-B9DE-1C61781077DC © 2016 The Trustees of the Natural History Museum, London 2016. All Rights Reserved

International audience; Polychelidan lobsters (Decapoda: Polychelida) are crustaceans with extant species which are restricted to deep water environments. Fossil species, however, used to live in more varied palaeoenvironments, from shallow water to deep water, and were more diverse morphologically. We redescribe two species of polychelidan lobsters, the Late Triassic Rosenfeldia triasica Garassino, Teruzzi & Dalla Vecchia, 1996 and the Late Jurassic Eryon oppeli Woodward, 1866, recently assigned to the same genus, Rosenfeldia, based upon only a few characters. Our investigation of all available material of both species leads us to distinguish these two species and to erect Rogeryon gen. nov. to accommodate Eryon oppeli. The palaeobiology of both species is interpreted for the first time. Rosenfeldia triasica with its stout first pereiopods and mandibles with both incisor and molar processes (documented for the first time in Polychelida) was benthic and probably fed either on slow-moving sedentary preys or was a scavenger. Rogeryon oppeli gen. et comb. nov. was benthic, visually adapted to shallow water palaeoenvironments, and possibly had a diet similar to that of slipper lobsters and horseshoe crabs. The redescription of these two species highlights the palaeobiological diversity of fossil polychelidans.

International audience; The third Cretaceous Aeshnoptera in amber is described from Myanmar. It represents a new family Burmaeshnidae fam. nov., genus and species Burmaeshna azari gen. et sp. nov. Its exact affinities remain uncertain but it is probably the sister group of the Late Cretaceous family Enigmaeshnidae. This discovery supports the hypothesis of an intense period of appearance of many aeshnopteran subclades during the late Early Cretaceous and the Late Cretaceous.

International audience; Mesomegaloprepus magnificus gen. et sp. nov. (Odonata: Zygoptera) is described from more than 14 specimens in eight pieces of mid-Cretaceous (earliest Cenomanian, ca. 99 Ma) amber from Myanmar. Possible phylogenetic affinities with the Neotropical Latibasaliidae, Thaumatoneuridae, and Pseudostigmatinae are discussed, and a relationship with Pseudostigmatinae considered as possible, but because of conflicting evidence separate family status as Mesomegaloprepidae fam. nov. is tentatively preferred. The remarkable degree of homoplastic conflict in the wing venational similarities indicates that these represent relatively weak evidence for phylogenetic relationships. The palaeoecology, including sexual dimorphism in wing colouration, of the new taxon is discussed, and the large number of inclusions explained with possible breeding behaviour in association with water-filled tree holes (phytotelmata) of the amber tree, similar to extant Pseudostigmatinae. The position of all alleged fossil Thaumatoneuridae are discussed and revised: Eothaumatoneura ptychoptera Pongracz, 1935 from the Eocene Geiseltal locality is restored in Thaumatoneuridae. Cretaceous Euarchistigma and Paleogene Eodysagrion are tentatively retained as subfamilies Euarchistigmatinae and Eodysagrioninae in Thaumatoneuridae. Paleogene Dysagrioninae and Petrolestinae are removed from Thaumatoneuridae and attributed to a restored family Dysagrionidae, and Paleocene Latibasaliidae is transferred from Amphipterygoidea to Epallagoidea.

Phylogenomics is extremely powerful but introduces new challenges as no agreement exists on ‘standards’ for data selection, curation and tree inference. We use jawed vertebrates (Gnathostomata) as a model to address these issues. Despite considerable efforts in resolving their evolutionary history and macroevolution, few studies have included a full phylogenetic diversity of gnathostomes, and some relationships remain controversial. We tested a new bioinformatic pipeline to assemble large and accurate phylogenomic datasets from RNA sequencing and found this phylotranscriptomic approach to be successful and highly cost-effective. Increased sequencing effort up to about 10 Gbp allows more genes to be recovered, but shallower sequencing (1.5 Gbp) is sufficient to obtain thousands of full-length orthologous transcripts. We reconstruct a robust and strongly supported timetree of jawed vertebrates using 7,189 nuclear genes from 100 taxa, including 23 new transcriptomes from previously unsampled key species. Gene jackknifing of genomic data corroborates the robustness of our tree and allows calcul a ting genome-wide divergence times by overcoming gene sampling bias. Mitochondrial genomes prove insufficient to resolve the deepest relationships because of limited signal and among-lineage rate heterogeneity. Our analyses emphasize the importance of large, curated, nuclear datasets to increase the accuracy of phylogenomics and provide a reference framework for the evolutionary history of jawed vertebrates. The use of genomic data to reconstruct phylogenetic relationships is powerful but challenging. Here, the authors develop a bioinformatics pipeline and use phylogenomic datasets to reconstruct the evolutionary relationships of jawed vertebrates.

International audience; Erymid lobsters (Decapoda, Erymidae) are a relatively abundant family of decapod crustaceans with a presumed conservative morphology. For these reasons, numerous species of erymids have been synonymized with others by early efforts to review the family. Eryma greppini Oppel, 1861, is one of these. A well-preserved specimen of erymid lobster assigned to this species has recently been traced in the palaeontological collections from the Université Claude Bernard Lyon 1 (France). Study of this specimen and examination of the type material of Eryma greppini, Eryma affinis Ferry, 1865, and Eryma bedeltum (Quenstedt, 1857) lead us to consider Eryma greppini to be a valid species, characterized by a peculiar pair of dorsal domes. A lectotype is herein designated for Eryma greppini. This study is a first step toward the necessary revision of erymid lobsters and proves the importance of taxonomic studies based on type material.

A new Jurassic fossiliferous Plattenkalk has been discovered at Monte Fallano (Caserta, Campania, southern Italy). Biostratigraphic analyses indicate a Bajocian/Bathonian age (Middle Jurassic). The fossil assemblage consists of terrestrial plants, invertebrates (bivalves, gastropods, decapod crustaceans, isopods and insect larvae) and vertebrates (fishes). This study takes terrestrial plants, fishes, and decapod crustaceans into account, giving systematic, taphonomic and palaeoenvironmental considerations. The land flora consists of impressions of sterile and fertile shoots of microphyllous conifers; leaves with parallel venation of unknown taxonomy are also present. The genera Cupressinocladus, Brachyphyllum and Araucarites are documented and their microscopical characters are examined. Plant remains possibly represent a stable biotope, as floral composition presents no variation along the section studied. Taphonomic considerations on plant fossils suggest parautochtonous deposition. The study of the rich decapod crustacean fauna includes Acanthochirana liburiaensis n. sp. (Aegeridae Burkenroad, 1963), Casertanus sabellicus n. gen., n. sp. (Sergestidae dana, 1852), Eryma osciensis (Erymidae Van Straelen, 1925) and Tethyseryon campanicus n. gen., n. sp. (Eryonidae de Haan, 1841). Casertanus sabellicus n. gen., n. sp. is the oldest representative of Sergestidae in the fossil record, extending the stratigraphic range of this family into the Middle Jurassic. Tethyseryon campanicus n. gen., n. sp. is the earliest species in which juveniles have been identified within the Eryonidae; the presence of both juveniles and adults in the depositional environment of Monte Fallano suggests that this species was autochthonous or parautochthonous. Preliminary data on fossil fishes sample have lead to the identification of leptolepid, macrosemiid among which Notagogus (Neonotagogus) denticulatus, pleuropholid (Pleuropholis) and pycnodontid fishes; other primitive teleosts and incomplete and indeterminate “ganoid” fishes are also reported. Based on the sedimentological data and the characteristics of decapod crustaceans and fishes, the investigated record of the Monte Fallano section represents the product of depositional process in shallow water carbonate platform settings.

International audience; BACKGROUND: Modern representatives of Polychelida (Polychelidae) are considered to be entirely blind and have largely reduced eyes, possibly as an adaptation to deep-sea environments. Fossil species of Polychelida, however, appear to have well-developed compound eyes preserved as anterior bulges with distinct sculpturation. METHODS: We documented the shapes and sizes of eyes and ommatidia based upon exceptionally preserved fossil polychelidans from Binton (Hettangian, United-Kingdom), Osteno (Sinemurian, Italy), Posidonia Shale (Toarcian, Germany), La Voulte-sur-Rhône (Callovian, France), and Solnhofen-type plattenkalks (Kimmeridgian-Tithonian, Germany). For purposes of comparison, sizes of the eyes of several other polychelidans without preserved ommatidia were documented. Sizes of ommatidia and eyes were statistically compared against carapace length, taxonomic group, and outcrop. RESULTS: Nine species possess eyes with square facets; Rosenfeldia oppeli (Woodward, 1866), however, displays hexagonal facets. The sizes of eyes and ommatidia are a function of carapace length. No significant differences were discerned between polychelidans from different outcrops; Eryonidae, however, have significantly smaller eyes than other groups. DISCUSSION: Fossil eyes bearing square facets are similar to the reflective superposition eyes found in many extant decapods. As such, they are the earliest example of superposition eyes. As reflective superposition is considered plesiomorphic for Reptantia, this optic type was probably retained in Polychelida. The two smallest specimens, a Palaeopentacheles roettenbacheri (Münster, 1839) and a Hellerocaris falloti (Van Straelen, 1923), are interpreted as juveniles. Both possess square-shaped facets, a typical post-larval feature. The eye morphology of these small specimens, which are far smaller than many extant eryoneicus larvae, suggests that Jurassic polychelidans did not develop via giant eryoneicus larvae. In contrast, another species we examined, Rosenfeldia oppeli (Woodward, 1866), did not possess square-shaped facets, but rather hexagonal ones, which suggests that this species did not possess reflective superposition eyes. The hexagonal facets may indicate either another type of superposition eye (refractive or parabolic superposition), or an apposition eye. As decapod larvae possess apposition eyes with hexagonal facets, it is most parsimonious to consider eyes of R. oppeli as apposition eyes evolved through paedomorphic heterochrony. CONCLUSION: Polychelidan probably originally had reflective superposition. R. oppeli, however, probably gained apposition eyes through paedomorphosis.

With nearly 100,000 species, the Acercaria (lice, plant lices, thrips, bugs) including number of economically important species is one of the most successful insect lineages. However, its phylogeny and evolution of mouthparts among other issues remain debatable. Here new methods of preparation permitted the comprehensive anatomical description of insect inclusions from mid-Cretaceous Burmese amber in astonishing detail. These “missing links” fossils, attributed to a new order Permopsocida, provide crucial evidence for reconstructing the phylogenetic relationships in the Acercaria, supporting its monophyly, and questioning the position of Psocodea as sister group of holometabolans in the most recent phylogenomic study. Permopsocida resolves as sister group of Thripida + Hemiptera and represents an evolutionary link documenting the transition from chewing to piercing mouthparts in relation to suction feeding. Identification of gut contents as angiosperm pollen documents an ecological role of Permopsocida as early pollen feeders with relatively unspecialized mouthparts. This group existed for 185 million years, but has never been diverse and was superseded by new pollenivorous pollinators during the Cretaceous co-evolution of insects and flowers. The key innovation of suction feeding with piercing mouthparts is identified as main event that triggered the huge post-Carboniferous radiation of hemipterans, and facilitated the spreading of pathogenic vectors.

International audience; Polychelidan lobsters (Crustacea: Decapoda) are abundant in the celebrated Middle Jurassic (Callovian)Lagerstätte of La Voulte-sur-Rhône (Ardèche, France). Among them, Eryon giganteus Van Straelen, 1923,is recognized by its large, rounded carapace. The generic assignment of this species has been particularlycomplicated, with many conflicting assignments proposed since the first description of the species. Thepresent study reinvestigates E. giganteus following the rediscovery of its lectotype. Careful examinationsreveal that the type material is composite: the lectotype belongs to a species of eryonid that wasdescribed recently as Cycleryon romani Audo, Schweigert, Saint Martin & Charbonnier, 2014, and isquite rare (six specimens); the rest of the material, and most specimens formerly assigned to E. giganteuscorrespond to an abundant species of Proeryon Beurlen, 1928 (33 specimens) that we herein describeas Proeryon charbonnieri n. sp. The present study also allows us to reinvestigate the generic assignmentof E. giganteus. Detailed observations allowed assigning E. giganteus to Soleryon Audo, Charbonnier,Schweigert & Saint Martin, 2014 based upon: the grooves marked across the dorsal part of carapace; aposterior carina near the posterior margin; and a hepatic carina between cervical and hepatic grooves.This taxonomic revision also leads to abandon Proeryon zehentbaueri, the replacement name whichwas proposed for Proeryon giganteus Beurlen, 1930.; Les Polychelida (Crustacea: Decapoda) sont abondants dans le célèbre Lagerstätte Jurassique moyen (Callovien) de La Voulte-sur-Rhône (Ardèche, France). Parmi eux, Eryon giganteus Van Straelen, 1923, est reconnaissable à sa grande carapace arrondie. L’assignation générique de cette espèce a été particulièrement complexe, de nombreuses assignations génériques contradictoires ayant été proposées. La présente étude révise cette espèce suite à la redécouverte de son lectotype. Un examen attentif du matériel type démontre qu’il est composite : le lectotype appartient à une espèce d’eryonidé assez rare (six spécimens connus) avec laquelle Cycleryon romani Audo, Schweigert, Saint Martin & Charbonnier, 2014 est mis en synonymie ; le reste du matériel type et la plupart des spécimens précédemment assignés à E. giganteus correspondent à une nouvelle espèce de Proeryon Beurlen, 1928 assez abondante (33 spécimens), ici nommée Proeryon charbonnieri n. sp. La présente étude nous permet également de résoudre l’assignation générique d’E. giganteus. Cette espèce est assignée à Soleryon Audo, Charbonnier, Schweigert & Saint Martin, 2014 en raison de ses sillons marqués sur toute la face dorsale de la carapace, sa carène postérieure près de la marge postérieure de la carapace et sa carène hépatique visible entre le sillon cervical et hépatique. Ces actes taxonomiques impliquent également l’abandon du nom de remplacement Proeryon zehentbaueri, qui avait été proposé pour Proeryon giganteus Beurlen, 1930.

This note describes the first record of the chocolate shrimp-goby Cryptocentrus malindiensis (Smith, 1959) from Réunion island, based on photographic evidence. A specimen of an estimated total length of 7 cm was photographed at 9:00 AM on 8 November 2012, at a water temperature of 26°C and depth of 8 m, on a prehistoric lava flow of the Piton de la Fournaise volcano. The habitat included shallow-water sea cracks and rocky overhangs, near basaltic muddy sandy bottoms, with a high hard substrate cover of calcareous algae, encrusting sponges and hydroids without coral, reflecting a low-light environment at these latitudes. Significant siltation, probably caused by a nearby river mouth, suggested the presence of a relatively low wave and current energy, which could be the effect of the confined nature of the habitat., Cette note présente le premier signalement du gobie de Malindi Cryptocentrus malindiensis (Smith, 1959) à la Réunion, sur la base de preuves photographiques. Un spécimen d’une longueur totale d’environ 7 cm a été photographié à 9:00, le 8 novembre 2012, par 8 m de profondeur, dans une eau à 26°C, sur une coulée de lave préhistorique du Piton de la Fournaise. L’habitat se composait de failles et de surplombs rocheux peu profonds, près de fonds sablo-vaseux basaltiques, avec un recouvrement important des substrats durs par les algues calcaires, les éponges encroûtantes et les hydraires, témoignant sous ces latitudes d’un environnement à faible luminosité. Un envasement significatif, probablement généré par la proximité d’une embouchure de rivière, suggère la présence de conditions hydrodynamiques modérées, qui pourraient être dues à la nature confinée de l’habitat.

International audience; This note describes the first record of the chocolate shrimp-goby Cryptocentrus malindiensis (Smith, 1959) from Réunion island, based on photographic evidence. A specimen of an estimated total length of 7 cm was photographed at 9:00 AM on 8 November 2012, at a water temperature of 26°C and depth of 8 m, on a prehistoric lava flow of the Piton de la Fournaise volcano. The habitat included shallow-water sea cracks and rocky overhangs, near basaltic muddy sandy bottoms, with a high hard substrate cover of calcareous algae, encrusting sponges and hydroids without coral, reflecting a low-light environment at these latitudes. Significant siltation, probably caused by a nearby river mouth, suggested the presence of a relatively low wave and current energy, which could be the effect of the confined nature of the habitat.; Cette note présente le premier signalement du gobie de Malindi Cryptocentrus malindiensis (Smith, 1959) à la Réunion, sur la base de preuves photographiques. Un spécimen d’une longueur totale d’environ 7 cm a été photographié à 9:00, le 8 novembre 2012, par 8 m de profondeur, dans une eau à 26°C, sur une coulée de lave préhistorique du Piton de la Fournaise. L’habitat se composait de failles et de surplombs rocheux peu profonds, près de fonds sablo-vaseux basaltiques, avec un recouvrement important des substrats durs par les algues calcaires, les éponges encroûtantes et les hydraires, témoignant sous ces latitudes d’un environnement à faible luminosité. Un envasement significatif, probablement généré par la proximité d’une embouchure de rivière, suggère la présence de conditions hydrodynamiques modérées, qui pourraient être dues à la nature confinée de l’habitat.

Fauna Europaea provides a public web-service with an index of scientific names (including important synonyms) of all extant multicellular European terrestrial and freshwater animals and their geographical distribution at the level of countries and major islands (east of the Urals and excluding the Caucasus region). The Fauna Europaea project comprises about 230,000 taxonomic names, including 130,000 accepted species and 14,000 accepted subspecies, which is much more than the originally projected number of 100,000 species. Fauna Europaea represents a huge effort by more than 400 contributing taxonomic specialists throughout Europe and is a unique (standard) reference suitable for many user communities in science, government, industry, nature conservation and education. The Diptera–Brachycera is one of the 58 Fauna Europaea major taxonomic groups, and data have been compiled by a network of 55 specialists.Within the two-winged insects (Diptera), the Brachycera constitute a monophyletic group, which is generally given rank of suborder. The Brachycera may be classified into the probably paraphyletic 'lower brachyceran grade' and the monophyletic Eremoneura. The latter contains the Empidoidea, the Apystomyioidea with a single Nearctic species, and the Cyclorrhapha, which in turn is divided into the paraphyletic 'aschizan grade' and the monophyletic Schizophora. The latter is traditionally divided into the paraphyletic 'acalyptrate grade' and the monophyletic Calyptratae. Our knowledge of the European fauna of Diptera–Brachycera varies tremendously among families, from the reasonably well known hoverflies (Syrphidae) to the extremely poorly known scuttle flies (Phoridae). There has been a steady growth in our knowledge of European Diptera for the last two centuries, with no apparent slow down, but there is a shift towards a larger fraction of the new species being found among the families of the nematoceran grade (lower Diptera), which due to a larger number of small-sized species may be considered as taxonomically more challenging.Most of Europe is highly industrialised and has a high human population density, and the more fertile habitats are extensively cultivated. This has undoubtedly increased the extinction risk for numerous species of brachyceran flies, yet with the recent re-discovery of Thyreophora cynophila (Panzer), there are no known cases of extinction at a European level. However, few national Red Lists have extensive information on Diptera.For the Diptera–Brachycera, data from 96 families containing 11,751 species are included in this paper.

International audience; Placodontia, an enigmatic group of durophagous and in part heavily armoured animals, were members of Sauropterygia, the most diverse and successful group of Mesozoic marine reptiles. Microanatomy and histology of long bones of several armoured and non-armoured Placodontia were studied, covering most of their taxonomic breadth, to elucidate the paleoecology, physiology , and lifestyle of its members. Results reveal an unexpected and not phylogenetically or stratigraphically related disparity of microanatomical and histological features for the group. The non-armoured Paraplacodus and the heavily armoured Psepho-derma grew with lamellar-zonal bone tissue type, which is typical for modern sauropsids. In the former, the tissue is nearly avascular surrounding a compacted medullary region, whereas in the latter, the lamellar-zonal bone tissue is vascularized framing a large open medullary cavity and a perimedullary region. Armoured Henodus and Placodontia indet. aff. Cyamodus as well as non-armoured Placodus exhibit a reduced medullary cavity and grew with highly vascularized plexiform to radiating fibro-lamellar bone. Several long bones of Placodontia indet. show circumferential fibro-lamellar bone and can be distinguished into two groups on the basis of microanatomical features. In addition, all bones that grew with fibro-lamellar bone show locally primary spongeous-like architecture and had secondarily widened primary osteons throughout the cortex, resulting in a secondarily spongeous tissue. The highly vascularized fibro-lamellar bone of these Placodontia indicates growth rates comparable to that of open marine ichthyosaurs. Differences in microanatomy and bone histology as expressed by a principal component analysis, thus clearly indicate different paleoecolo-gies, including differences in lifestyle and swimming modes and capabilities in Placodontia. This would have reduced competition in the shallow marine environments of the Tethys and might be a key to their success and diversity. A certain developmental plasticity among the studied placodonts is interpreted as response to different environmental conditions as is obvious from inter-and intraspecific histological variation. Most striking is the difference in life history strategy in armoured Psephoderma and non-armoured Paraplacodus when compared to armoured Henodus, Placodontia indet. aff. Cyamodus, non-armoured Pla-codus, and Placodontia indet. Bone tissue of Psephoderma and Paraplacodus indicates low growth rates and a low basal metabolic rate, as many modern sauropsids have such as the marine iguana, whereas the others grew with extremely fast growth rates, more typical for birds and mammals, indicating an increased basal metabolic rate.

Fauna Europaea provides a public web-service with an index of scientific names (including important synonyms) of all extant multicellular European terrestrial and freshwater animals and their geographical distribution at the level of countries and major islands (east of the Urals and excluding the Caucasus region). The Fauna Europaea project comprises about 230,000 taxonomic names, including 130,000 accepted species and 14,000 accepted subspecies, which is much more than the originally projected number of 100,000 species. Fauna Europaea represents a huge effort by more than 400 contributing taxonomic specialists throughout Europe and is a unique (standard) reference suitable for many user communities in science, government, industry, nature conservation and education. The Diptera-Brachycera is one of the 58 Fauna Europaea major taxonomic groups, and data have been compiled by a network of 55 specialists.Within the two-winged insects (Diptera), the Brachycera constitute a monophyletic group, which is generally given rank of suborder. The Brachycera may be classified into the probably paraphyletic 'lower brachyceran grade' and the monophyletic Eremoneura. The latter contains the Empidoidea, the Apystomyioidea with a single Nearctic species, and the Cyclorrhapha, which in turn is divided into the paraphyletic 'aschizan grade' and the monophyletic Schizophora. The latter is traditionally divided into the paraphyletic 'acalyptrate grade' and the monophyletic Calyptratae. Our knowledge of the European fauna of Diptera-Brachycera varies tremendously among families, from the reasonably well known hoverflies (Syrphidae) to the extremely poorly known scuttle flies (Phoridae). There has been a steady growth in our knowledge of European Diptera for the last two centuries, with no apparent slow down, but there is a shift towards a larger fraction of the new species being found among the families of the nematoceran grade (lower Diptera), which due to a larger number of small-sized species may be considered as taxonomically more challenging.Most of Europe is highly industrialised and has a high human population density, and the more fertile habitats are extensively cultivated. This has undoubtedly increased the extinction risk for numerous species of brachyceran flies, yet with the recent re-discovery of Thyreophora cynophila (Panzer), there are no known cases of extinction at a European level. However, few national Red Lists have extensive information on Diptera.For the Diptera-Brachycera, data from 96 families containing 11,751 species are included in this paper.

International audience; Le Lagerstätte de La Voulte-sur-Rhône (Jurassique moyen) livre une communauté bathyale très bien conservée et présentant une forte biodiversité dominée par les arthropodes. Les crustacés Polychelida Scholtz & Richter, 1995 y sont particulièrement abondants et initialement représentés par Eryon ellipticus Van Straelen, 1923, Proeryon giganteus (Van Straelen, 1923), Hellerocaris falloti (Van Straelen, 1923), et Willemoesiocaris ovalis (Van Straelen, 1923). Cette nouvelle étude révèle l’existence de deux nouveaux genres et de trois espèces nouvelles : Voulteryon parvulus n. gen., n. sp., Cycleryon romani n. sp., qui est l’espèce la plus ancienne de ce genre, et Adamanteryon fourneti n. gen., n. sp., un Polychelida énigmatique aux affinités demeurant incertaines. Le genre Proeryon Beurlen, 1928 est également révisé afin de résoudre un problème d’homonymie, ce qui nous conduit à proposer le nom de remplacement Proeryon zehentbaueri pro Proeryon giganteus Beurlen, 1930, non Proeryon giganteus (Van Straelen, 1923). Ces nouveaux résultats montrent que la communauté de Polychelida de La Voulte est la première en terme de diversité familiale (trois familles) et générique (sept genres), et la seconde en terme de diversité spécifique (sept espèces), juste derrière le Jurassique supérieur du Lagerstätte d’Eichstätt (huit espèces). Grâce à la tomographie aux rayons X, des caractères anatomiques encore jamais observés sont décrits, tels que les appendices thoraciques chez Proeryon giganteus et Hellerocaris falloti. Chez Hellerocaris falloti, la mise en évidence de ces appendices semble indiquer qu’il s’agit d’une des espèces fossiles les plus proches des polychelidés actuels.

International audience; The slow dragonet is a rare marine species of the family Callionymidae, and is endemic to Reunion and Mauritius and possibly the other Mascarene Islands. It is grey in colour with small round white spots aligned on the flanks and a honeycomb pattern on the cheeks and the snout (Fig. 1a-c). The apices of the first dorsal spines are yellow and the tail is about one-third of the total length. It was described from preserved material and presumed to occur on sand, probably adjacent to rocks and corals, at depths of around 30 m, possibly also deeper (Fricke et al., 2009). It was classed as near-threatened, with populations probably declining due to human activities (Fricke et al., 2009). This little-known species has never been previously observed in its natural environment. Here, we report upon an adult male of C. aagilis (total length: 12 cm), found in the company of females and photographed at sunset on 20 April 2013 in very shallow water (

International audience; The Late Jurassic plattenkalks from Europe are remarkable for their exquisitely preserved crustaceans. New specimens of polychelidan lobsters (Crustacea, Decapoda, Polychelida) from the Lagerstatten of Cerin (France), Canjuers (France), Wattendorf (Germany) and Zandt (Germany) are described and increase the palaeobiodiversity of Jurassic eryonids. Soleryon gen. nov. is described from the Cerin, Wattendorf and Zandt Lagerstatten while ¨ Cycleryon bourseaui sp. nov. is described from the Cerin and Canjuers Lagerstatten. ¨ Soleryon amicalis gen. et sp. nov. from Cerin and S. schorri sp. nov. from Wattendorf show cephalothoracic grooves that are not observed within any other fossil eryonids. Their patterns of cephalothoracic grooves are similar to those observed in extant polychelids and confirm the affinities of eryonids and polychelids. The problematic assignment of Eryon perroni Etallon, 1859 from the Oxfordian nodules of eastern France is solved and leads to the new combination Soleryon perroni (Etallon, 1859). These new eryonids are preserved in anatomical connection and thus suggest they used to live in proximity to their depositional environments. They may have inhabited the coral reefs neighbouring the lagoons and/or buried themselves in the carbonate mud of the lagoon margins at the origin of the plattenkalks. The cooccurrences of Soleryon gen. nov. and Cycleryon Glaessner, 1965 in four subcontemporaneous Lagerstatten clearly suggest connections between the Bavarian (Wattendorf, Zandt), the Jura (Cerin) and the Provence (Canjuers) platforms. For the first time, several species of crustaceans highlight and confirm the palaeobiogeographical links between the French and German plattenkalks at the end of the Jurassic.

International audience; First record of Pseudanthias bicolor (Serranidea) from different artificial habitats at Reunion Island.Despite the large number of studies on fish populations of coral reef areas of Reunion island during the past forty years, the bicolor anthias Pseudanthias bicolor (Randall, 1979), previously recorded from Mauritius and the Maldives in the Indian Ocean, was never observed on the coral reefs of the island. Recently, two specimens of were photographed on different artificial habitats during scientific monitoring programs in scuba diving. This study, based en morphologic and morphometric evidences, validates the identification of these specimens as P. bicolor, and therefore represents the westernmost record of the species in the Indian Ocean. In a general context of degradation of coral reef habitats and considering the difficult access to certain non-reef habitats (e.g. depth, large surface area, distance from a port), the example of P. bicolor presented in this study illustrates the importance of artificial habitats for the observation of marine fish diversity. These small habitats of substitution, often monitored according to European regulations, allow occasional identification of new fish species, monitoring of exotic invasive populations or observation of rare species.; Malgré le nombre élevé d’études réalisées sur les peuplements ichtyologiques des zones récifales de l’île de la Réunion au cours des quarante dernières années, l’anthias bicolore Pseudanthias bicolor (Randall, 1979), précédemment recensé à Maurice et aux Maldives dans l’océan Indien, n’a jamais été observé sur les récifs coralliens de l’île. Deux spécimens de cette espèce ont été photographiés récemment sur des habitats artificiels lors de suivis scientfiques en plongée sous-marine. La présente étude, fondée sur des données morphologiques et morphométiques, valide l'identification de ces spécimens comme P. bicolor et constitue ainsi le signalement le plus occidental de l’espèce dans l’océan Indien. Dans un contexte général de dégradation des habitats récifaux et d'accès difficile à certains habitats naturel non-récifaux (e.g. profondeur, surface importantes, éloignement d’un port), l’exemple de P. bicolor présenté dans cette étude illustre l’intérêt des habitats artificiels comme observatoires de la diversité ichtyologique marine. Ces habitats de substitution aux petites surfaces d'emprise, souvent suivis scientifiquement selon la réglementation européenne en vigueur, permettent le signalement occasionnel de nouvelles espèces de poissons, le suivi de populations exotiques en extension ou l’observation d’espèces rares.

International audience; Ichthyosaurs rapidly diversified and colonised a wide range of ecological niches during the Early and Middle Triassic period, but experienced a major decline in diversity near the end of the Triassic. Timing and causes of this demise and the subsequent rapid radiation of the diverse, but less disparate, parvipelvian ichthyosaurs are still unknown, notably because of inadequate sampling in strata of latest Triassic age. Here, we describe an exceptionally large radius from Lower Jurassic deposits at Penarth near Cardiff, south Wales (UK) the morphology of which places it within the giant Triassic shastasaurids. A tentative total body size estimate, based on a regression analysis of various complete ichthyosaur skeletons , yields a value of 12–15 m. The specimen is substantially younger than any previously reported last known occurrences of shastasaurids and implies a Lazarus range in the lowermost Jurassic for this ichthyosaur morphotype.

For a long time, the genus Knebelia Van Strae- len, 1922 has comprised two species of eryonid lobster, K. bilobata (M€ 1839) and K. schuberti (Meyer, 1836), both recorded exclusively from Late Jurassic Lagerst€ in southern Germany. Recently, the latter has been suggested to represent a juvenile individual of Cycleryon propinquus (Schlotheim, 1822). A re-examination of the type and new material has led to our rejection of that interpretation and confirmation of assignment of this species to Knebelia. Two specimens, both possessing short frontal lobes, from plat- tenkalks at Nusplingen (late Kimmeridgian) and at Solnho- fen (early Tithonian), respectively, are here assigned to a new species, K. totoroi sp. nov. This new species and a review of K. bilobata have furnished new insights into the origin and function of the frontal lobes, which are expan- sions articulated to the front of the carapace. They probably functioned as rudders facilitating 'tail-flip swimming' as observed in the paddle-like antennae of extant scyllarids (Eucrustacea, Decapoda, Scyllaridae). The rudder-like lobes identified in Knebelia may therefore represent a case of con- vergent evolution.

International audience; Palaeophis maghrebianus belongs to the Palaeo-phiinae (Palaeophiidae). This snake subfamily is relatively poorly known, and it is mainly represented by disarticulated vertebrae and ribs and by a few vertebral segments. Its intracol-umnar variability remains also poorly understood. The discovery of new isolated vertebrae and vertebral segments of Palaeophis maghrebianus in the Ypresian (Lower Eocene) Phosphates of Morocco enables us to provide a more detailed diagnosis of this species and to describe its intracolumnar variability. Moreover, the new material reveals that this species could reach gigantic size being, with Palaeophis colossaeus, one of the two longer palaeophiids. The microanatomical and histological analysis of some vertebrae illustrating diverse positions along the vertebral column reveals the presence of osteosclerosis, especially in the anterior and mid-precloacal regions. The occurrence of this osseous specialization implies a role in buoyancy and body trim control in this taxon, which is considered a shallow marine dweller based on its anatomical features and geological data. Palaeophis maghrebianus also displays a dense vascular network suggesting a growth speed, and thus a metabolic rate, much higher than in the biggest extant snakes.

Cratonepa enigmatica gen. and sp. nov., an enigmatic new nepoid bug, is described from the Lower Cretaceous Crato formation in Brazil. Although its general habitus is strikingly similar to that of the Cenozoic and recent Nepidae, it has several plesiomorphic characters, the most obvious being the siphon retractiled into the abdomen, which supports a basal position as a sister group of either all Nepidae or even Nepoidea. The morphology of its legs suggests that it was a walking predator living in mud or in aquatic vegetation, as for extant Nepidae, although the absence of a long siphon suggests a very different way of breathing.

National audience; Sommaire du dossier : Travail de réforme et réforme du travail. Métiers en évolution, émergence d'un encadrement - Les délégations territoriales, terres à conquérir... - Structurer l'animation territoriale : un défi pour les délégations territoriales - Animation territoriale : une place à trouver pour les délégations territoriales - Un an après la mise en oeuvre des services - ASP (Agence de services et de paiement) : 5 ans de gestion de la VAE.

International audience; The prey choice of extinct cave lions Panthera spelaea was determined using bone collagen isotopic signatures in the Belgian Ardennes and the Swabian Jura between 40,000 and 25,000 years ago as well as in the Late-glacial of the northwestern Alp foreland and of the Paris Basin. More than 370 specimens of large carnivorous and herbivorous mammals from 25 sites coeval with cave lion were analyzed. The isotopic results point to an individualistic prey choice for cave lions, with some individuals more oriented on reindeer and others on young cave bears. The isotopic signatures and therefore dietary choice of cave lions did not overlap with those of cave hyenas, indicating competitive exclusion between the large predators. The most recent western European cave lions seem to have been consuming mainly reindeer until the local extirpation of this prey species, which coincides chronologically with their own extinction. This restricted prey choice may be involved in the extinction of this large predator in Western Europe. Ó 2011 Elsevier Ltd and INQUA.

16 pages; International audience; Palaeozoic and Mesozoic cephalopod conchs occasionally reveal dark organic coatings at the aperture. A number of these coatings, including still unrecorded examples, are described, figured and interpreted herein. On the basis of elemental analysis, actualistic comparison and a comparison with Triassic bivalves, some of these coatings are shown to consist of apatite and primarily probably of conchiolin (and also probably melanin). In several Mesozoic ammonoid genera such as Paranannites, Psiloceras, Lytoceras, Phylloceras, Harpoceras and Chondroceras, some of these coatings (recorded herein for most of these taxa for the first time) are interpreted as a structure similar to the black band, which was previously known only from Recent Allonautilus and Nautilus. In contrast to these nautilid genera, however, the organic material of some Mesozoic ammonoids was not deposited on the inside of the shell but externally, albeit positioned at the terminal aperture as in Recent nautilids. Some ammonoids of Carboniferous and Triassic age show several such bands at more or less regular angular distances on the ultimate whorls and at the aperture, e.g. Nomismoceras, Gatherites, Owenites, Paranannites, Juvenites and Melagathiceratidae gen. et sp. nov. Triassic material from Oman shows that the black coating was probably secreted from the inside, because the position of this organic deposit changes from interior to exterior in an anterior direction (i.e. adaperturally). This structure has previously been referred to as a ‘false colour pattern' and is here interpreted as having been formed at an interim aperture or megastria (‘alter Mundrand'). All structures discussed in the paper are considered to have been secreted by a single organ and to have been initiated by some form of stress or adverse conditions. Thus, certain environmental parameters and growth anomalies appear to have influenced their formation.