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Sender L.M.,University of Zaragoza | Gomez B.,University Claude Bernard Lyon 1 | Gomez B.,French National Center for Scientific Research | Diez J.B.,University of Vigo | And 4 more authors.
Review of Palaeobotany and Palynology | Year: 2010

An aquatic angiosperm, Ploufolia cerciforme gen. et comb. nov., is reported from the Upper Albian of the Utrillas Formation at the Plou locality, Teruel Province, north-eastern Spain. Ploufolia cerciforme shows eccentric peltate attachment, elliptic to obovate nanophylls, one medial primary vein and lateral veins that dichotomize several times before merging into an intramarginal vein, which links small glands that occur on the convex portions of the marginal undulations. Ploufolia cerciforme shows most affinities with extant Nymphaeales and both sedimentological and taphonomic evidence supports a freshwater lacustrine habit for P. cerciforme. The presence of marginal glands in leaves of P. cerciforme is related to a leaf guttation mechanism, as occurs in plants living in water saturated habitats. By the Albian, aquatic angiosperms were already well diversified and often dominant in western European wetland environments. © 2010 Elsevier B.V. All rights reserved. Source


Cuenca-Bescos G.,University of Zaragoza | Rofes J.,University of Zaragoza | Lopez-Garcia J.M.,Rovira i Virgili University | Blain H.-A.,Rovira i Virgili University | And 7 more authors.
Quaternary International | Year: 2010

Thousands of fossils of small vertebrates are recorded in one of the most complete stratigraphic sequences of the continental European Pleistocene, in the Sierra de Atapuerca. This sequence, with a few interruptions, spans the last 1.5 million years. The stratigraphic series is recorded in six karstic cavities in the Sierra de Atapuerca. From the oldest record to the most modern one, these are the Sima del Elefante, Gran Dolina, Galería-Zarpazos, Sima de los Huesos, El Portalón and El Mirador. The faunal successions of continental microvertebrates have made it possible to divide the Atapuerca sequence into 7 faunal units (Atapuerca Faunal Units, ATA FUs), which are based on the first and last local appearances of taxa (LO, HO). The Spanish Quaternary small vertebrate faunas are grouped into 5 distinct biozones, from the oldest to the most recent: Allophaiomys pliocaenicus, Allophaiomys lavocati, Allophaiomys chalinei, Iberomys brecciensis and Iberomys cabrerae. These are calibrated with radiometric and palaeomagnetic dating, allowing the proposal of a continental biochronological scale for the Pleistocene of the Iberian Peninsula. © 2009 Elsevier Ltd and INQUA. Source


Martinell J.,Paleontologia i Geociencies marines | Domenech R.,Paleontologia i Geociencies marines | Aymar J.,2 rue des Chvrefeuilles | Kowalewski M.,Virginia Polytechnic Institute and State University
Palaios | Year: 2010

Preexisting fossil collections, often the only source of data from sites that are no longer accessible, have been widely used in systematics but underutilized in quantitative paleontological studies. Here, the potential utility and limitations of materials obtained from preexisting collections is explored using a paleoecological case example (confamilial predation by drilling naticid predators). Specimens of the gastropod Cochlis pseudoepiglottina were collected from a single locality (Nidolères outcrop, Pyréné es-Orientales Département, southern France) of an unnamed, early Pliocene unit; the site is currently inaccessible. A statistical analysis of 183 specimens, representing three separate collections, indicates that these datasets are quantitatively consistent and provide interpretable numerical data on various aspects of drilling predation patterns. Despite various limitations, the results indicate that (1) intense confamilial predation affected C. pseudoepiglottina; (2) drilling attacks may have been size selective; (3) the frequency of failed attacks recorded by incomplete drill holes was high; and (4) the ratio of successful attacks declined dramatically with increase in snail size, suggesting a strong size-refuge effect. Our interpretation is hampered by the exclusion of the smaller size classes of C. pseudoepiglottina and a lack of bulk-sampled, assemblage-level quantitative data on all fossil taxa at this taxonomically diverse site. Nevertheless, the results provide a useful addition to previous literature on drilling predation, including quantitative data that are potentially applicable in meta-analytical compilations (e.g., prey effectiveness). Despite limitations, preexisting collectionsespecially those representing fossil sites that no longer exist or are inaccessiblecan yield useful quantitative data. © 2010 SEPM (Society for Sedimentary Geology). Source


da Silva C.M.,University of Lisbon | Landau B.,University of Lisbon | Domenech R.,Paleontologia i Geociencies marines | Martinell J.,Paleontologia i Geociencies marines
Palaeogeography, Palaeoclimatology, Palaeoecology | Year: 2010

The Pliocene molluscan assemblage from the Mondego Basin (Portugal, Western Iberia) plays a particularly important role in the understanding of the palaeobiogeography of Neogene-Quaternary molluscs of the Atlantic Frontage of Europe and the western Mediterranean. The importance of these Portuguese molluscan deposits is stressed, as it is the only assemblage representative of the southern portion of the Pliocene French-Iberian biogeographical Province. The Pliocene marine fossiliferous deposits of the Mondego Basin (central-west Portugal) are dated using their nannofossil and molluscan assemblages, as well as Strontium dating. The results suggest a late Zanclean to early Piacenzian age. Chronologically they are equivalent to the Mediterranean Pliocene Molluscan Unit 1 (MPMU1). However, due to the more northern geographical location of the Mondego Basin assemblages, their molluscan content is closer to that of MPMU2 than to that of MPMU1 in the Mediterranean. The presence of a stock of thermophilic taxa in the Mondego assemblage, no longer existent in European waters, enabled us to suggest a palaeoenvironmental reconstruction for mid-Pliocene SSTs in the region. We put forward the hypothesis that the SSTs at the latitude of Mondego, during late Zanclean to early Piacenzian, would be characterized by a yearly SST pattern analogous to that of present-day Cape Blanc (West Africa). Consequently, whilst subtropical conditions existed in the Atlantic Zanclean to mid-Piacenzian at Mondego latitude in the Mediterranean fully tropical conditions prevailed at that time. The Mondego SST estimates correlate with those estimated for MPMU2 in the Mediterranean. The global palaeoenvironmental reconstruction of mid-Pliocene SSTs in the PRISM2 Project suggests, for western Iberia, at Mondego latitude, an August SST of about 23 °C, and a February temperature of about 17 to 18 °C. Our hypothesis suggests similar August SST differing in only half a degree Celsius (23.5 vs. 23 °C) and February SSTs slightly higher (19 vs. 17-18 °C). © 2009 Elsevier B.V. All rights reserved. Source


Sanjuan J.,Paleontologia i Geociencies marines | Martin-Closas C.,Paleontologia i Geociencies marines
Palaeogeography, Palaeoclimatology, Palaeoecology | Year: 2012

A micropalaeontological study of the non-marine Upper Eocene of the north eastern Ebro Basin (Catalonia, Spain) was carried out to clarify the palaeoecology of well-known charophyte species that are widely recognised as significant in charophyte biostratigraphy. Autochthonous specimens of the biozone index-species Harrisichara vasiformis-tuberculata were found in marlstones from the Sant Boi Formation (middle part of the Priabonian), which are associated with brackish water ponds laterally related to paralic marshes. In contrast, laterally equivalent assemblages found in white laminated marls from stable freshwater lakes were devoid of the index species and were dominated by Harrisichara lineata. Three more charophyte assemblages are reported from the continental Artés Formation (Stephanochara vectensis biozone, Upper Priabonian). Assemblages dominated by the species Nodosochara jorbae, reported only from Iberia at that age, occur in marlstones related to freshwater, temporary and turbid lakes within flood plains in medial fluvial fan environments. However, Lychnothamnus grambastii dominates locally in similar environments with higher organic matter content. Laterally equivalent assemblages from freshwater perennial lakes in distal alluvial fan facies were dominated by the biozone index-species Harrisichara tuberculata.These results provide evidence that important charophyte index species of the European charophyte biozonation were controlled by palaeoenvironmental factors such as water salinity, lake level changes or terrigenous input to the lakes. In consequence, these species should be used with caution in biostratigraphic studies, taking into account that their presence or absence may be palaeoecologically driven. © 2012 Elsevier B.V. Source

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