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The paper deals with newly discovered Valanginian-Hauterivian fauna of heteromorphic ammonites (Ancyloceratina) from locality south of the village of Leše above the Meža River valley (North Karavanke Mountains). Fossils were recovered from the pelagic limestone. Among the studied heteromorphic ammonites are Lower Cretacaoeus species Himantoceras trinodosum (Upper Valanginian) and Crioceratites cf. nolani (Hauterivian). Based on the accompanied ammonites (Ammonitina) from the outcrop, we biostratigraficaly confirm the presence of Lower Cretaceous ammonites fauna in the Northern Karavanke Mountains. This is also the first report on heteromorphic ammonites in Slovenia.

International audience; Ashdown Brickworks, near Bexhill, East Sussex, has produced a large number of vertebrate fossils from the Wadhurst Clay Formation, part of the Wealden Supergroup (Hastings Group; Valanginian; Lower Cretaceous). Here we describe the microvertebrate fauna of the ‘conglomerate bed’, representing a rich sample of taxa. While most of the recovered teeth and bones are abraded, some heavily, most can be identified to species level. The taxa include four species of hybodont sharks (Egertonodus basanus, Planohybodus ensis, Polyacrodus parvidens, P. brevicostatus), three taxa of bony fishes (an unidentified Lepidotes-like semionotiform, the pycnodontiform Ocloedus, and an albuliform), three taxa of crocodyliforms (the goniopholid Hulkepholis, a bernissartiid, and the atoposaurid Theriosuchus), and the theropod dinosaurs Baryonyx and an allosauroid. Sediments of the Wadhurst Clay Formation as a whole indicate freshwater to very slightly brackish-water environments of deposition, and the mainly aquatic time-averaged mixture of fishes and tetrapods recovered from the ‘conglomerate bed’, together with isolated terrestrial species, confirms this interpretation.

Lower Cretaceous (Valanginian) dendritic microfabrics occur in karstic cavities within fine-grained shallow-marine platform carbonates at San Lorenzello, southern Italy. They form dense micritic masses and clusters, generally oriented perpendicularly to cavity surfaces, surrounded by layered sparry cement. Individual dendrites, typically sub-millimetric in size, have highly irregular margins and form distinctive shrub-like masses ranging from compact and squat, to elongate and highly branched. The centimetric and irregularly elongate cavities appear to have formed through subaerial exposure, and are almost entirely filled by the micritic dendrites and associated sparry crusts. In size, shape and micritic composition, the dendrites broadly resemble a variety of similar fabrics, including hot spring travertine shrubs and calcified microfossils such as Cambrian Angusticellularia, which has analogs in present-day lacustrine calcified cyanobacteria. However, the San Lorenzello dendrites differ in occupying small cavities. This cryptic microkarstic dripstone setting, together with the often regular spacing and appearance of these dendritic fabrics, may be more consistent with an abiotic origin. These comparisons underscore the challenge of interpreting microdendritic carbonates fabrics in general.

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

Some of the best records of continental vertebrates from theCretaceous of Europe come from Romania, particularly two well-knownoccurrences of dwarfed and morphologically aberrant dinosaurs and othertaxa that lived on islands (the Cornet and Hațeg Island faunas).Substantially less is known about those vertebrates living in the morestable, cratonic regions of Romania (and Eastern Europe as a whole),particularly during the earliest Cretaceous. We describe one of the fewearly Early Cretaceous fossils that have ever been found from theseregions, the tooth of a large theropod dinosaur from Southern Dobrogea,which was discovered over a century ago but whose age and identificationhave been controversial. We identify the specimen as coming from theValanginian stage of the Early Cretaceous, an incredibly poorly sampledinterval in global dinosaur evolution, and as belonging toCarcharodontosauridae, a clade of derived, large-bodied apex predatorswhose earliest Cretaceous history is poorly known. Quantitative analysesdemonstrate that the Romanian tooth shows affinities with a derivedcarcharodontosaurid subgroup, the Carcharodontosaurinae, which until nowhas been known solely from Gondwana. Our results suggest that thissubgroup of colossal predators did not evolve vicariantly as Laurasiasplit from Gondwana, but originated earlier, perhaps in Europe. Thecarcharodontosaurine diversification may have been tied to a north-tosouthtrans-Tethyan dispersal that took place sometime between theValanginian and Aptian, illustrating the importance of palaeogeographicties between these two realms during the largely mysterious early-midEarly Cretaceous.

The Mesozoic chondrichthyan fossil record from northern South America is scarce and poorly known containing only a few reports of lamniform and ptychodont species from the Upper Cretaceous of Colombia and Venezuela. Here, we report the discovery of two associated (found together) dorsal fin spines of a hybodont shark from the Valanginian deposits of the Rosablanca Formation (Andes of Colombia). This hybodont along with the presence of ammonites and other mollusks, turtles, plesiosaurs and ichthyosaurs support a marine depositional environment for this geological unit. Although both spines described here are fragmentary and without diagnostic characters to allow identification to generic level, their finding represents the first record of this shark group from northernmost part of South America and northwestern margin of Gondwana. This new record expands the known distribution of this group of sharks during Lower Cretaceous.

The gastropod fauna of the Lower Cretaceous of the Argentinian Neuquén Basin contains three aporrhaid species. Protohemichenopus neuquensis Camacho, 1953 is the most abundant, longest-lived, and most geographically widespread of the aporrhaids of this basin, and its protoconch and early teleoconch whorls were unknown until now. The new species Dimorphosoma weaveri features convex to subtly angular spire whorls with opisthocyrt collabral ribs that are more prominent towards the mid-whorl, a bicarinate last whorl with small rounded nodes on the adapical carina, a simple, falcate labral wing which is more or less rectangular proximally and tapering and curving towards its distal end, and a short, straight rostrum. Tylostoma jaworskii Weaver, 1931 is now placed in Harpagodes, and other previous, scattered, coeval records of this genus in the basin are now recognized as part of this single species. It is believed that whereas H. jaworskii preferred shallower-water carbonate settings of low to moderate energy, P. neuquensis and D. weaveri favored siliciclastic to mixed clastic-carbonate environments, in deeper waters. In spite of its endemic elements, this aporrhaid association depicts a predominantly Tethyan influence. Fil: Cataldo, Cecilia Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos "Don Pablo Groeber". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos ; Argentina

Thalattosuchia was a diverse clade of marine crocodylomorphs known from the Early Jurassic to the Early Cretaceous. Recent studies have hypothesized that their extinction was two-phased: (1) habitat loss near/at the Jurassic-Cretaceous boundary heavily reduced their morphofunctional diversity, particularly in Europe, while (2) climate change and a shift in marine fauna during the Early Cretaceous (either at the Valanginian-Hauterivian boundary or during the early Hauterivian) finished off the already stressed clade. Unfortunately, the Cretaceous fossil record of thalattosuchians is poor, with only one putative “teleosaurid” specimen and approximately ten metriorhynchid specimens. Here we re-describe the youngest known teleosaurid from the Cretaceous (Valanginian of south-eastern France). Originally considered to be a teleosaurid (possibly Steneosaurus), we demonstrate that it belongs to Metriorhynchidae, and a newly discovered subclade, Plesiosuchina. It differs from Plesiosuchus in the pattern of tooth enamel ornamentation and the variation in dentary alveoli size. Referring this specimen to Metriorhynchidae means there are no definitive Cretaceous teleosaurid specimens. Furthermore, it suggests that both durophagous and piscivorous teleosaurids became extinct at the end of the Jurassic. Interestingly, this is the fourth metriorhynchid lineage known to cross the Jurassic-Cretaceous boundary. As such, it would appear that the two thalattosuchian families responded very differently to the lowering sea levels at the end of the Jurassic: teleosaurids possibly became extinct, while metriorhynchids were seemingly unaffected.

We present a new species of Steinmanella Crickmay from the Valanginian of the Neuquén Basin, west-central Argentina, and at the same time update a Valanginian-earliest Barremian bivalve zonation which is integrated into the local, Chilean and European standard ammonoid zonations. Steinmanella caicayensis sp. nov. presents a moderately inflated shell, a subtriangular outline, well-developed carinaeand a straight to moderately convex anterior margin. Steinmanella is very abundant in the Tithonian-Barremian interval in the basin and thus provides an ideal opportunity to perform detailed taxonomic and stratigraphic studies; a former zonation based on these trigonioids is here revised and expanded with a thorough revision of Valanginian occurrences based on new material. Two new zones are proposed, namely the S.quintucoensis and S.caicayensis zones, encompassing Valanginian times. The proposed bivalve zonation encompassing the Valanginian-earliest Barremian time interval can be useful in correlating with other southwestern Gondwanan regions, such as Perú, Chile, South Africa, Tanzania, and India, where Steinmanella has been recorded. Fil: Lazo, Dario Gustavo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos "Don Pablo Groeber". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos "Don Pablo Groeber"; Argentina Fil: Luci, Leticia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos "Don Pablo Groeber". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos "Don Pablo Groeber"; Argentina

El estudio de rasgos paleodemecológicos requiere de ciertas condiciones tafonómicas particulares. En la Formación Mulichinco (Valanginiano) se cumplen dichas condiciones, siendo frecuentes los signos de actividad de bivalvos excavadores que aparecen en sección transversal sobre las superficies de estratificación. Dos grupos de tales superficies fueron analizados, midiendo densidad poblacional, disposición espacial, distribución de tamaños y orientación en planta de las excavaciones. El paleoambiente se determinó por medio de un análisis sedimentológico detallado, y se registró la fauna de bivalvos presente con la intención de identificar a los potenciales productores. Se encontraron altas densidades poblacionales para ambos grupos, lo que indica condiciones físicas favorables y buen suministro de alimento, en tanto que la disposición espacial y la distribución de tamaños difiere entre dichos grupos; no se advirtió orientación preferencial en la mayoría de las superficies. El primer grupo (grupo A) muestra un patrón uniforme de disposición espacial y trazas de mayor tamaño; llama la atención la ausencia de pequeños tamaños. En el segundo grupo (grupo B), el patrón de disposición es indistinguible de uno al azar (salvo en un caso donde parece haber un patrón agregado). Se interpreta al grupo A como un conjunto de rastros de escape realizados por excavadores profundos en respuesta a depósitos de tormenta, en tanto que el grupo B es considerado como un conjunto de rastros de reposo/escape hechos por excavadores superficiales en ambientes dominados por mareas. Estudios paleodemecológicos de este tipo representan herramientas potencialmente útiles para los análisis sedimentológicos y de cuencas. The study of palaeodemecological features requires some particular taphonomic conditions. These conditions were met in the Mulichinco Formation (Valanginian), where burrowing bivalve trace fossils are widespread and often appear in cross section on bedding surfaces. Two groups of such beds were analyzed, measuring population density, spatial distribution, size distribution and horizontal orientation of the burrows. The palaeoenvironment was established by means of a detailed sedimentological analysis, and the bivalve fauna present was checked, in order to attempt identifying their potential producers. High population densities were found for both groups, indicating favourable physical conditions and good food supply, while differences in both spatial and size distributions were noticed between them; on most surfaces there was no preferred orientation. The first group (group A) showed a uniform pattern of spatial distribution and larger traces, with a remarkable absence of small sizes. In the second group (group B), the spatial distribution pattern is indistinguishable from a random distribution (except one case in which the pattern appears to be aggregated). Group A is interpreted as a set of escape traces made by deep burrowers in response to storm deposition, while group B is considered as resting/escape traces made by shallow burrowers in tide-dominated environments. Palaeodemecological studies of this kind are potentially useful tools for sedimentary and basin analyses. Fil: Echevarría, Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Paleozoología Invertebrados; Argentina Fil: Damborenea, Susana Ester. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Paleozoología Invertebrados; Argentina Fil: Manceñido, Miguel Oscar. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Paleozoología Invertebrados; Argentina

A revision of the calpionellid bio-chronostratigraphy in Western Sicily (Italy) was carried out, in order to update the taxonomy of this group, through the identification of some genera (Borziella, Longicollaria, Chitinoidella, Dobeniella, Sturiella, Borzaiella and Praecalpionellites) and species (Remaniella catalanoi POP, Remaniella duranddelgai POP, Remaniella colomi POP, Remaniella borzai POP, Remaniella filipescui POP) recorded for the first time in the area. The studied sections, belonging to the Trapanese and Saccense Domains (Western Sicily), include at the base the upper portion of the Rosso Ammonitico Unit (Upper Tithonian), followed by the Lattimusa Formation (Lower Cretaceous). The quantitative and biostratigraphic analysis of the calpionellid assemblages allowed us to identify 13 assemblages and to define some important bioevents for the Upper Tithonian–Valangianian interval. The recorded calpionellid bioevents allowed us to recognize Zone/Subzone schema, which have been correlated with the bio-chronostratigraphy previously proposed for the Western Tethys. Una revisione della biostratigrafia a Calpionellidi in sezioni della Sicilia Occidentale ha permesso di aggiornare la tassonomia di questo gruppo, con l’identificazione di generi (Borziella, Longicollaria, Chitinoidella, Dobeniella, Sturiella, Borzaiella e Praecalpionellites) e delle specie (Remaniella catalanoi Pop, Remaniella duranddelgai Pop, Remaniella colomi Pop, Remaniella borzai Pop, Remaniella filipescui Pop) rinvenuti per la prima volta in Sicilia Occidentale. Le sezioni studiate appartengono ai Domini Saccense e Trapanese. Tali sezioni sono caratterizzate alla base dell’ Unità Rosso Ammonitico e successivamente dalla Formazione della Lattimusa. L’analisi biostratigrafica e quantitativa delle associazioni a Calpionellidi ha permesso di identificare 13 associazioni e di caratterizzare alcuni eventi principali, nell’intervallo Titoniano superiore– Valanginiano. I bioeventi registrati hanno consentito di riconoscere Zone e Sottozone, che sono state corrrelate con gli schemi biostratigrafici proposti in precedenza per la Tetide occidenatale. Financial aid was provided by Research Project GV04B-629 (Generalitat Valenciana) and the Italian MURST, granted to G. Parisi, COFIN 1999 and 2001.

Three new species of belemnite, Duvalia hispanica sp. nov. (late early Valanginian), Castellanibelus? bonti sp. nov. (earliest late Valanginian) and Pseudoduvalia nana sp. nov. (late Hauterivian), belonging to the family Duvaliidae Pavlow are described from sedimentary rocks in southeast Spain (Tornajo Mountain). Castellanibelus? bonti represents an unusual, very depressed species, whereas Pd. nana represents the smallest belemnite species so far described. These new species originate from outer platform deposits.

The small heteromorphic ammonites from the Berriasian, lower Valanginian and Barremian strata of the Río Argos succession (west of Caravaca, southeast Spain) are described. One new genus is introduced, Sabaudiella (type species Ancyloceras sabaudianum Pictet & de Loriol, 1858), and three new species, Sabaudiella argosensis (small paraspinoid shell), Protancyloceras obscurocostatum (weak retroverse ribs with small ventrolateral tubercles) and P.? evolutum (evolute shell with occasional fibulation).

Belemnites have been sampled and investigated from three successions (Río Argos, Cañada Lengua and Tornajo) with different palaeobathymetries. In this way an excellent opportunity has been created to compare the distribution of belemnites, both stratigraphically and with regard to palaeo-water depth. These successions are well studied with respect to ammonites. Pseudobelus is abundant only in the deep water settings, contrary to Castellanibelus. Hibolithes seems to be restricted to certain strata, being relatively common in the outer platform succession (Tornajo). The Cañada Lengua and Tornajo successions are interpreted sequence stratigraphically. Generally, the Cañada Lengua is characterised by ‘highstand’ stacking, while the absence of lowstand deposits and the presence of marly highstand deposits characterises the Tornajo succession. The new genus Gillieronibelus (type species Belemnites mayeri Gilliéron, 1873) is described. The genus Coctebelus Weis, 1991, is regarded as a junior synonym of Berriasibelus Delattre, 1952. The genera Conobelus and Berriasibelus have different stratigraphical distributions. Three new species are described; Conobelus? piradoensis sp. nov., Duvalia miravetesensis sp. nov. and Duvalia tornajoensis sp. nov. There is an important belemnite faunal change in the lower Alpillensis Zone, were the position of the Berriasian-Valanginian boundary is favoured to be placed on top of sequence Be 7.

Three new species of belemnite, Duvalia hispanica sp. nov. (late early Valanginian), Castellanibelus? bonti sp. nov. (earliest late Valanginian) and Pseudoduvalia nana sp. nov. (late Hauterivian), belonging to the family Duvaliidae Pavlow are described from sedimentary rocks in southeast Spain (Tornajo Mountain). Castellanibelus? bonti represents an unusual, very depressed species, whereas Pd. nana represents the smallest belemnite species so far described. These new species originate from outer platform deposits.

The small heteromorphic ammonites from the Berriasian, lower Valanginian and Barremian strata of the Río Argos succession (west of Caravaca, southeast Spain) are described. One new genus is introduced, Sabaudiella (type species Ancyloceras sabaudianum Pictet & de Loriol, 1858), and three new species, Sabaudiella argosensis (small paraspinoid shell), Protancyloceras obscurocostatum (weak retroverse ribs with small ventrolateral tubercles) and P.? evolutum (evolute shell with occasional fibulation).