115 research outputs found
A Tylosaurine Mosasauridae (Squamata) from the Late Cretaceous of the Basque-Cantabrian Region
An isolated mosasaurid tooth from the Campanian of Alava (Basque Country), previously referred to as cf. Mosasaurus sp., is here reattributed to a tylosaurine. It may belong to Tylosaurus, a nearly cosmopolitan genus known from the Santonian-Maastrichtian. This is the first occurrence of a tylosaurine mosasaurid in the Iberian Peninsula. Moreover, it corresponds to the southernmost occurrence of this clade in the northern margin of the Mediterranean Tethys. ylosaurinae fossils are known from North America, Europe, New Zealand, Antarctica, Africa and Asia, but remain unknown from the southern Mediterranean Tethyan margin and from tropical palaeolatitudes.Un diente aislado de mosasaurio procedente del Campaniense de Álava (País Vasco), previamente asignado a cf. Mosasaurus sp., se atribuye en este trabajo a un tilosaurino. Podría pertenecer a Tylosaurus, un género cuasi cosmopolita del Santoniense-Maastrichtiense. Es la primera cita de un mosasáurido tilosaurino en la Península Ibérica. Además, se trata del registro más meridional de este clado en el margen norte del Tetis mediterráneo. Los Tylosaurinae están representados por fósiles en Norteamérica, Europa, Nueva Zelanda, Antártida, África y Asia, pero carecen de registro en el margen sur del Tetis mediterráneo y en paleolatitudes tropicales
Theropod dinosaurs from the upper cretaceous of the south pyrenees basin of Spain
The dinosaur record in the South Pyrenees Basin is diverse and rich. A total of 142 theropod teeth were studied for this paper, which constitutes one of the richest samples for these remains in Europe. Eight upper Campanian to upper Maastrichtian outcrops from the Pyrenees produced six non-avian theropod taxa (Theropoda indet., Coelurosauria indet., ?Richardoestesia, ?Dromaeosauridae indet., ?Pyroraptor olympius, ?Paronychodon). These six taxa are added to two previously described theropods (a Richardoestesia-like form and a possible ornithomimosaurid), indicating that there was considerable theropod diversity on the Iberian Peninsula during the Late Cretaceous. © 2015 L. Xing et al
Taphonomy and palaeohistology of ornithischian dinosaur remains from the Lower Cretaceous bonebed of La Cantalera (Teruel, Spain)
The fossiliferous site of La Cantalera-1 (Teruel, Spain) has to date provided remains of more than 30 vertebrate taxa, including dinosaurs, crocodyliforms, pterosaurs, mammals, lizards, turtles, lissamphibians and teleosteans. Located in the lower part of the Blesa Formation (lower Barremian), it is one of the richest vertebrate-bearing deposits from the Lower Cretaceous of the Iberian Peninsula. In this work, taphonomic and palaeohistological studies are carried out on the basis of ornithischian (Ornithopoda and Ankylosauria) dinosaur samples in order to assess the diagenetic processes, to characterize the histological microstructures and, if possible, to make palaeobiological inferences about the state of maturation of the individuals. A variety of techniques are used in the taphonomic study, including scanning electron microscopy (SEM), cathodoluminescence (CL), X-ray diffraction (XRD) and ultraviolet fluorescence (UVF). The bone of the dinosaur samples has been converted into francolite (fluorapatite carbonate); the trabecular cavities are filled with semi-spherical forms of goethite and two different phases of calcite. In addition, the SEM and UVF techniques suggest the activity of coccoid-form bacteria and filaments of bacterial origin (biofilms?) in the bones, which possibly favoured fossilization. The dinosaur remains were subjected to fossil-diagenetic processes in a phreatic environment after a rapid burial, without appreciable seasonality effects. On the other hand, the palaeohistological study of both skeletal and dermal bones found in La Cantalera-1 shows a community of herbivorous dinosaurs composed mostly of immature ornithopods and at least one Polacanthus-like ankylosaur, as suggested by the organizational pattern of structural collagen fibres seen in some samples. The palaeobiological inferences drawn from this study support previous interpretations of a relative abundance of immature ornithischians in La Cantalera-1
First description of ornithopod dinosaur skeletal remains from the Villar del Arzobispo Formation (JurassicCretaceous transition): Cerrito del Olmo locality (Alpuente, Valencia, E Spain)
[EN] The Villar del Arzobispo Formation (Tithonian-Berriasian) in Teruel and Valencia provinces (SE Iberian
Range) has yielded abundant skeletal remains of dinosaurs, mainly of sauropods and stegosaurs. Three
vertebrae collected in the locality of Cerrito del Olmo I (Alpuente, Valencia province), two of them previously
referred to the stegosaurid Dacentrurus armatus, belong in fact to an ornithopod. The material consists of
one cervical and two caudal centra that preserve the base of the neural arch fused to the centrum. These
remains are here assigned to Ornithopoda indet. on the basis of the combination of several characters
more frequent in ornithopods than in stegosaurs. This is the first description of ornithopod skeletal remains
from the Villar del Arzobispo Formation.Investigación financiada por los proyectos CGL2007-64061/BTE (X.P.S, J.C.) y CGL2007/62469/BTE (J.I.R.-O.) del Ministerio de Ciencia e Innovación, el grupo de investigación GIC 07/14-361 del Gobierno Vasco/EJ (X.P.S.) y el Protocolo de colaboración CN-04-226 entre la Consejería de Cultura y Turismo del Principado de Asturias y la Universidad de Oviedo (J.I.R-O). Nuestro agradecimiento a la Dra. Margarita Belinchón (MCNV) por su ayuda durante el estudio del material, y a la Dra. Gloria Cuenca-Bescós por la revisión del trabajo.Pereda-Suberbiola, X.; Ruiz-Omeñaca, JI.; Company Rodríguez, J. (2010). Primera descripción de restos esqueléticos de dinosaurio ornitópodo en la Formación. Villar del Arzobispo (tránsito Jurásico-Cretácico): yacimiento de Cerrito del Olmo (Alpuente, Valencia). Geogaceta. 47:13-16. http://hdl.handle.net/10251/150357S13164
Archosaurian teeth (Crocodyliformes, Theropoda) from the Late Jurassic of BuÒol (Valencia province, E Spain)
[EN] Five isolated archosaurian teeth from Valencia province (eastern Spain) are studied in this work. They
have been found in the ¿Cantera CarcalÌnª site, an outcrop of the marine Higueruelas Formation (Tithonian)
in the vicinity of BuÒol town. They represent the first direct evidence of tetrapods in this formation, in
which, up to the moment, only dinosaur tracks had been found in a locality of the adjacent Teruel province.
Four of the teeth pertain to crocodyliforms, three to indeterminate crocodyliforms and another to a
teleosaurid identified as cf. Machimosaurus sp., a taxon already known in the Kimmeridgian of the Iberian
Peninsula (Asturias and Portugal). The fifth tooth is assigned to a theropod dinosaur, probably an allosauroid.El equipo de investigación del MUJA está subvencionado por el Protocolo de colaboración CN-04-226 entre la Consejería de Cultura y Turismo del Principado de Asturias y la Universidad de Oviedo. Este trabajo es una contribución a los proyectos CGL2007-62469/BTE(J.I.R-O) y CGL2007-64061/BTE (X.P.S,J.C.) del Ministerio de Ciencia e Innovación, y del grupo de investigación del Gobierno Vasco GIC07/14-361 (X.P.S.).Agradecemos a José Ignacio Canudo (Universidad de Zaragoza) y Francisco Ortega (UNED) la revisión crítica del manuscritoRuiz-Omeñaca, JI.; Pereda-Suberbiola, X.; Company Rodríguez, J.; Belinchón, M. (2010). Dientes de arcosaurios (Crocodyliformes, Theropoda) del Jurásico Superior de Buñol (Valencia). Geogaceta. 48:35-38. http://hdl.handle.net/10251/150323S35384
Primera cita de cocodrilos zifodontos en el Cenozoico de Asturias: Royo Gómez y los supuestos dientes de dinosaurio del Eoceno de Llamaquique
In 1928, José Royo Gómez mentioned the find of “two teeth similar to those of theropod dinosaurs from the Secondary” in the Eocene of Llamaquique (Oviedo Basin, Asturias). Royo Gómez was aware of the interest of the discovery, “because they would be the youngest remains found of these gigantic reptiles”. According to the hitherto unpublished documents preserved in the Archives of the Museo Nacional de Ciencias Naturales in Madrid, Royo Gómez photographed five teeth from Llamaquique in April 1932, which he regarded as belonging to theropods. The whereabouts of this material is currently unknown. However, the revision of the Llamaquique collection in the above mentioned museum has allowed to recover one labiolingually compressed and serrated tooth (ziphodont condition). We reject here that the tooth belongs to a theropod, and we assign it to a Mesoeucrocodylia indet. This is the first mention of the discovery of ziphodont crocodyliforms in the Paleogene of Asturias.En 1928, José Royo Gómez informó del hallazgo de “dos dientes idénticos a los de los Dinosaurios terópodos del Secundario” en el Eoceno de Llamaquique (Cuenca de Oviedo, Asturias). Royo Gómez era consciente del interés de este descubrimiento, “pues serían los restos más modernos que se conocerían de estos gigantescos reptiles”. Según la documentación conservada en el Archivo del Museo Nacional de Ciencias Naturales en Madrid, hasta ahora inédita, Royo Gómez fotografió en abril de 1932 cinco dientes de Llamaquique que él consideraba pertenecientes a terópodos. Este material se encuentra actualmente en paradero desconocido. No obstante, la revisión de la colección paleontológica de Llamaquique en el mencionado museo ha permitido recuperar un diente comprimido lateralmente y provisto de carenas denticuladas (condición zifodonta). Se descarta que el diente pertenezca a un terópodo, asignándose a un Mesoeucrocodylia indeterminado. Se trata de la primera mención del hallazgo de cocodrilos zifodontos en el Paleógeno de Asturias
Primeros datos magnetoestratigráficos y nuevos yacimientos del Maastrichtiense superior en Huesca (sector noroccidental de la Cuenca de Tremp).
Las facies continentales de la Cuenca de Tremp contienen uno de los abundantes registros con vertebrados continentales del final del Cretácico en Europa. Esta área de los Pirineos es un lugar excepcional para estudiar la extinción de los vertebrados continentales en el límite Cretácico-Paleógeno (K-Pg) al ser uno de los pocos lugares de Europa con un registro sedimentario continuo de depósitos continentales del Campaniense superior al Daniense. En el entorno de Serraduy, localizado en el flanco noroeste del sinclinal de Tremp, se han recuperado abundantes restos de vertebrados en los últimos años, destacando la presencia de dinosaurios hadrosáuridos y crocodilomofos eusuquios. Sin embargo, aunque provisionalmente estos yacimientos se han situado en el Maastrichtiense superior, nunca habían sido datados con métodos absolutos o relativos. En este trabajo se exponen por primera vez los resultados preliminares de datación magnetoestratigráfica en este sector, permitiendo asignar estos yacimientos a una edad Maastrichtiense superior dentro de los crones C30n y C29r. Estos resultados confirmarían que los yacimientos de vertebrados del área de Serraduy son unos de los más modernos del Cretácico Superior de Europa estando muy cercanos al límite K-Pg.
The continental facies of the Tremp Basin contain one of the best continental vertebrate record from the Upper Cretaceous of Europe. Therefore, this area of the Pyrenees is an exceptional place to study the extinction of continental vertebrates across the Cretaceous-Paleogene boundary (K-Pg) being one of the few places in Europe that has a continuous record of continental deposits ranging from the upper Campanian to Danian. The area of Serraduy, located on the northwest flank of the Tremp syncline, has reported abundant vertebrate remains in recent years, highlighting the presence of hadrosaurid dinosaurs and eusuchian crocodylomorphs. Nevertheless, although these deposits have been provisionally assigned as Maastrichtian, they never had been dated with absolute or relative methods. This paper presents for the first time the preliminary magnetostratigraphic dating results in this sector, allowing to assign these vertebrate sites to a late Maastrichtian age within the polarity chrons C30n and C29r. These results confirm that the vertebrate sites of the Serraduy area are among the most modern in the Upper Cretaceous of Europe, being very close to the K-Pg boundary
A New Crocodylian from the Late Maastrichtian of Spain: Implications for the Initial Radiation of Crocodyloids
The earliest crocodylians are known primarily from the Late Cretaceous of North America and Europe. The representatives of Gavialoidea and Alligatoroidea are known in the Late Cretaceous of both continents, yet the biogeographic origins of Crocodyloidea are poorly understood. Up to now, only one representative of this clade has been known from the Late Cretaceous, the basal crocodyloid Prodiplocynodon from the Maastrichtian of North America.The fossil studied is a skull collected from sandstones in the lower part of the Tremp Formation, in Chron C30n, dated at -67.6 to 65.5 Ma (late Maastrichtian), in Arén (Huesca, Spain). It is located in a continuous section that contains the K/P boundary, in which the dinosaur faunas closest to the K/P boundary in Europe have been described, including Arenysaurus ardevoli and Blasisaurus canudoi. Phylogenetic analysis places the new taxon, Arenysuchus gascabadiolorum, at the base of Crocodyloidea.The new taxon is the oldest crocodyloid representative in Eurasia. Crocodyloidea had previously only been known from the Palaeogene onwards in this part of Laurasia. Phylogenetically, Arenysuchus gascabadiolorum is situated at the base of the first radiation of crocodyloids that occurred in the late Maastrichtian, shedding light on this part of the cladogram. The presence of basal crocodyloids at the end of the Cretaceous both in North America and Europe provides new evidence of the faunal exchange via the Thulean Land Bridge during the Maastrichtian
Magnetoestratigrafía del Cretácico Superior del sector Occidental de las Sierras Exteriores (Pirineo Occidental); implicaciones bioestratigráficas.
El Cretácico Superior del sector más Occidental de las Sierras Exteriores (Sa de Sto. Domingo) está escasamente representado en potencia pero presenta las facies más someras y transicionales donde se han recuperado recientemente restos de vertebrados fósiles (Osteichthyes, Chondrichthyes y Dinosauria), algunos de los cuales son de carácter continental. En este trabajo se presentan los resultados del análisis magnetoestratigráfico llevado a cabo en 4 secciones de pequeña potencia situadas entre los meridianos de San Felices y de Luesia (Prov. de Zaragoza). La magnetización característica de estas rocas es estable, primaria y muestra dos polaridades del campo magnético. La correlación tentativa entre perfiles, unida al conocimiento de las asociaciones de vertebrados existente en la cuenca de Graus-Tremp, permiten proponer una correlación preliminar que relacionaría los niveles fosilíferos con el cron C32n (Campaniense) y las facies Garum con los crones C29r, C29n y C28r (Maastrichtiense y Daniense) de la escala global de polaridad magnética. Esta correlación conlleva un hiato sedimentario durante el Maastrichtiense que deberá ser revisado en futuros estudios sedimentológicos
A 3D REPOSITORY OF DINOSAUR TEETH: THE GENERATION OF OPEN RESOURCES FOR THE CLASSIFICATION AND IDENTIFICATION OF SPECIMENS
Among the many valuable uses of the artificial intelligence in the field of museums, it may assist the classification of out-of-context items. This paper deals with the problem of the identification of dinosaur teeth (a type of fossil that is usually found scattered), which can be tackled by means of multivariate algorithms (such as the principal components, discriminant or cluster analyses) taking as a starting point a series of morphometric values (i.e., distances between specific points of the fossil tooth). A good interpretation requires some comprehension regarding the mathematical algorithms that are used, as well as the specific knowledge in palaeontology that permits appreciating the actual reach of the results. However, based on metric values as the computations are, there must also be some control over their precision and the possibility of checking the old measurements or complete the list of morphometric variables. This is an aspect that may be solved if the three-dimensional models of the teeth are made publicly available.The text describes the 3D documentation of a set of twelve fossil teeth of the museum of Natural Sciences of Álava (Vitoria-Gasteiz, Spain) —approximately from 1 to 6 cm in size— using a structured light scanner and close-up photographs for recording some features smaller than the resolution of the scanner. The information about each tooth was then packed and uploaded to the university repository, from where it is also accessible via cultural and scientific aggregators (such as Europeana); likewise, reduced resolution copies are also accessible in the commercial platform Sketchfab®.</p
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