Otolithes de poissons pliocènes du sud-est de la France

Otoliths collected from nine localities in the Lower and Middle Pliocene blue marls of southern France revealed the presence of 118 teleost taxa, including 80 named species. Three new species are introduced: Pseudophichthys escaravatierensis, "genus Bythitinorum" vonhachti and Cepola neogenica. The associations studied belong to five different biozones of planktonic foraminifera in the Lower and Middle Pliocene. The relationships of these Pliocene teleost faunas to the Tortonian and Recent Mediterranean faunas are analysed. Because major problems exist in matching otolith-based species with those erected for osteological material from Messinian localities, our comparisons are based exclusively on data obtained from the otoliths. Fifty of our 80 identified species appear only in the Pliocene. This indicates that at the beginning of the Piocene, the Mediterranean realm was subject to extensive faunal replacement. All the studied associations indicate higher temperatures than those of the present day Mediterranean. In the studied area, the associations from the basal Pliocene (Spaeroidinellopsis Acme-zone) at Saint-Martin-du-Var clearly indicate a bathyal environment, corresponding to depths of 300-500 m or even more. Ascending the stratigraphic column, the successive associations in the Pliocene rias of Southeastern France indicate decreasing depths, corresponding to the progressive filling of these basins. In the studied area, data on the teleosts of the terminal Pliocene are lacking, but faunas of this age are known from Southern Italy. They show that the Paleomediterranean fauna, which was substantially modified at the beginning of the Pliocene, appears near the end of this period as a warm water fauna, trapped in a basin where deterioration of climatic conditions led progressively to extinction. The Recent bathyal fauna of the Mediterranean appears extremely impoverished, but the littoral fauna conserves certain aspects of warmer waters, as is apparent in the prolific evolution of gobiids, labrids and blenniids

Révision de quelques Odontaspididae (Neoselachii: Lamniformes) du Paléocène et de l'Eocène du Bassin de la mer du Nord

The revision of some Odontaspididae species from the Paleocene and the Eocene of the North sea Basin has clarified the generic status of some of them and to precise their dental morphologies. A species from the Lutetian of Belgium, Carcharias sp., can be considered as the first representative of the lineage leading to the Recent species C. taurus. Three new genera are described: Brachycarcharias nov. gen. (Lutetian of Belgium), Orpodon nov. gen. (Selandian of Belgium) and Sylvestrilamia nov. gen. (Ypresian of England). The validity of the genus Hypotodus is confirmed and it is recommended that the poorly defined species hopei is abandoned in favour of the species verticalis in order to avoid confusion

The first three dimensional fossils of Cretaceous sclerorhynchid sawfish Asflapristis cristadentis gen et sp nov and implications for the phylogenetic position of the Sclerorhynchoidei (Chondrichthyes)

A new fossil batoid (ray) Asflapristis cristadentis gen. et sp. nov. is described from six exceptionally well-preserved, three-dimensional skeletal remains from the Turonian (Late Cretaceous) of Morocco. Mechanical and acid preparation and CT scanning of these specimens reveal details of much of the proximal skeleton, especially the skull, synarcual and pectoral skeleton, with only the more distal parts of the skeleton missing. These fossils represent a relatively large animal (62 cm preserved length, estimated total length to approximately 2 meters) possessing a robust rostrum that lacks enlarged rostral denticles. It has a narrow and small chondrocranium with jaws that are relatively large compared to the rest of the skull and robust with highly ornamented teeth that lack cusps. The branchial skeleton shows a large second hypobranchial without anterior process which was probably fused to the basibranchial as in other sclerorhynchoids. The synarcual is large and lacks centra through its entire length, and with no direct connection to the pectoral girdle was observed. Pectoral fins probably possessed enlarged proximal elements (propterygium, mesopterygium and metapterygium), the reduced articulation facet between the coracoid with the pectoral elements was reduced. A phylogenetic analysis using both parsimony and bayesian methods was performed incorporating this new taxon. Both analyses recovered a phylogenetic topology that places the sclerorhynchoids in a close relation to rajoids and clearly separated from the morphologically similar Pristidae within the Rhinopristiformes. In respect to the extant taxa, the phylogenies generated are similar to that obtained in molecular analysis of modern batoids. The palaeoecological implication of this discovery suggests that the Asfla assemblage was not from a ‘normal’ open carbonate shelf but rather a restricted environment favouring a low diversity chondrichthyan fauna

Sharks of the order Carcharhiniformes from the British Coniacian, Santonian and Campanian (Upper Cretaceous).

Bulk sampling of phosphate-rich horizons within the British Coniacian to Campanian (Upper Cretaceous) yielded very large samples of shark and ray teeth. All of these samples yielded teeth of diverse members of the Carcharhiniformes, which commonly dominate the fauna. The following species are recorded and described: Pseudoscyliorhinus reussi (Herman, 1977) comb. nov., Crassescyliorhinus germanicus (Herman, 1982) gen. nov., Scyliorhinus elongatus (Davis, 1887), Scyliorhinus brumarivulensis sp. nov., ? Palaeoscyllium sp., Prohaploblepharus riegrafi (Müller, 1989) gen. nov., ? Cretascyliorhinus sp., Scyliorhinidae inc. sedis 1, Scyliorhinidae inc. sedis 2, Pteroscyllium hermani sp. nov., Protoscyliorhinus sp., Leptocharias cretaceus sp. nov., Palaeogaleus havreensis Herman, 1977, Paratriakis subserratus sp. nov., Paratriakis tenuis sp. nov., Paratriakis sp. indet. and ? Loxodon sp. Taxa belonging to the families ?Proscylliidae, Leptochariidae, and Carcharhinidae are described from the Cretaceous for the first time. The evolutionary and palaeoecological implications of these newly recognised faunas are discussed

The impact of the Pull of the Recent on extant elasmobranchs

Modern elasmobranchs have a long evolutionary history and an abundant fossil record that consists mainly of teeth. Many fossil taxa have living representatives. However, the representation of extant taxa in the fossil record is unknown. To begin to understand the geological history of extant elasmobranchs, we here assess the quality of their fossil record. We do so by assessing the Pull of the Recent (POR). The POR can bias the fossil record because the rather complete record of living taxa allows palaeontologists to identify fossil members of the modern clades and to bridge time bins where fossils are absent. We assessed the impact of the POR by quantifying the proportion of extant elasmobranchs that have a fossil record, but do not occur in the last 5 million years (Pliocene and Pleistocene). We found that the POR does not affect orders and families, but it does affect 24% of elasmobranch genera. Within the different elasmobranch orders, the Lamniformes display the most complete generic fossil record, with no impact of the POR. Although modest, the impact of the POR in extant elasmobranch genera is higher than that found in other taxa. Overall, the geological history of elasmobranchs contradicts the usual assumption that the fossil record becomes worse backwards in time. This is the case across geographical regions and tooth size, further suggesting that sampling intensity and outcrop availability might explain the POR effect on sharks and rays

Découverte de vertébrés aquatiques présumés paléocènes dans les Andes septentrionales de Bolivie (Rio Suches, synclinorium de Putina)

Parmi les vertébrés aquatiques nouvellement découverts au nord du lac Titicaca (Bolivie) sont reconnus le téléostéen #Brychaetus$ et un crocodile dyrosauridé, fournissant la présomption d'un âge paléocène de la formation fossilifère. L'interprétation structurale de cette donnée chronologique est discutée (Résumé d'auteur

Sélaciens du Miocène terminal du bassin d'Alvalade (Portugal). Essai de synthèse

A rich uppermost Miocene selachian fauna from the Alvalade Basin (represented by more than 10.000 teeth) is accounted for. It is the most modern miocene fauna of neritic habit under warm-temperate to subtropical conditions, known in the european Miocene