José Ignacio Canudo

Several new localities bearing megalooithid eggs were discovered along of the Sierra de Loarre (Huesca, northeastern Iberian Peninsula), forming a sequence of paleontological sites bearing well-preserved fossil eggs. At the Santa Marina 1 site, the egg clutches occur at the top of extensively developed and vertically-stacked paleosols, while numerous isolated eggshells appear grouped in three roughly levels across the 1.5 m-thick of an alluvial profile subspherical to slightly ellipsoidal eggs with thick discretispherulithic eggshells and compatituberculated outer surface ornamentation are here assigned to Megaloolithus siruguei, in coherence with other Late Cretaceous localities of the Iberia and Europe. Many biological and taphonomic features based on the facies analysis, eggshell preservation and geochemical composition suggest reconsidering some aspects of the dinosaur nesting behavior, indicating that Santa Marina 1 could have been a recurrent nesting area, although in the last nesting horizon the number of unsuccessful eggs and anomalous eggshells are very common. The multidisciplinary study allows us to discriminate between biologic-induced against environmental-forced in the location of the sauropod egg accumulations, reconsidering some aspects about the origin of the paleontological sites and of the M. siruguei preservation.

Ornithopods are an extinct group of dinosaurs that were particularly abundant and diverse in the Cretaceous of the Iberian Peninsula, and whose abundance in the Maestrazgo Basin has allowed numerous taxa to be identified over the last decade. Many of these fossil remains are still taxonomically indeterminate and require a more detailed study on both a macroscopic and microscopic scale. In this contribution, an osteohistological analysis is carried out on a partial skeleton—composed of five incomplete vertebrae, two dorsal ribs, an ischium, a fibula, and a tibia—found in the province of Aliaga (Teruel, NE Spain). We identified a progressive slowdown in tissue apposition and a variation in the type of growth marks generated in every bone, allowing a more precise identification of the ontogenetic stage of the specimen as a subadult individual. The skeletochronological correlation between the different elements also suggests that the specimen reached sexual maturity at around seven years of age and died between nine and twelve years of age. Likewise, the usefulness of the three‐front model is proven for the first time in an ornithopod dinosaur, as a tool for analysing the histology expressed by the different bone elements of a single specimen and inferring their skeletochronological potential. Comparison with other ornithopod taxa reveals the great variability that each bone element shows depending on the taxon analysed, which prevents us from determining a single element suitable for studying the skeletochronology of any ornithopod taxon.

Las universidades atesoran un gran patrimonio derivado de su labor docente e investigadora, a menudo desconocido por la propia comunidad universitaria y por el público general. Los museos universitarios son los encargados de custodiar y poner en valor estas colecciones. El Museo Paleontológico de la Universidad de Zaragoza surgió en los años 80 como una necesidad de gestionar el patrimonio paleontológico generado por los propios investigadores de esta institución y adecuarse a la legislación existente. El Museo de Ciencias Naturales de la Universidad de Zaragoza (MCNUZ), heredero del anterior museo, es un museo activo y en constante crecimiento, que se encarga de la gestión de las colecciones de Ciencias Naturales de la Universidad, siendo la más destacable la Colección de Paleontología, compuesta por más de 42.000 ejemplares y 327 holotipos. Más allá de su gestión interna, el MCNUZ se está convirtiendo en el centro neurálgico de las actividades relacionadas con las ciencias naturales en la provincia de Zaragoza gracias a un amplio programa de charlas, presentaciones de libros y mesas debate, concursos dedicados al público juvenil y exposiciones temporales. Se trata, además, de un recurso de gran valor para la propia docencia universitaria. Los museos universitarios no sólo son imprescindibles para custodiar el patrimonio universitario, sino que también son una herramienta para la comunicación directa con la sociedad.

El yacimiento de Fondota (Abiego, Huesca) es uno los yacimientos con más fósiles de icnitas de vertebrados de la Cuenca del Ebro. Éstas presentan una gran variedad de grados de preservación morfológica (MP) por lo que resulta fundamental conocer las condiciones sedimentológicas bajo las que se desarrolló. El yacimiento, localizado en la parte inferior de la Formación Peraltilla (Oligoceno inferior), se sitúa en la superficie de un nivel de calizas grises masivas que presenta indicadores de escasa profundidad y desecación (nodulización, laminación estromatolítica…). El nivel calcáreo correspondió a un área encharcada desarrollada sobre depósitos de un relleno de canal en una zona aluvial distal. En dicha situación, las icnitas se originaron bajo diferentes condiciones con variaciones en la humedad y el contenido de agua del substrato. Estas condiciones tuvieron una influencia directa en los valores altos o bajos de MP, y, por tanto, en la presencia/ausencia de detalles anatómicos.

El yacimiento de Los Ibones supone una nueva aportación al conocimiento del registro icnológico de vertebrados del Mioceno de la Cuenca del Ebro. El yacimiento se encuentra en la superficie de un nivel de calizas en el tránsito entre las formaciones Uncastillo y Alcubierre. Se corresponde con depósitos en un área encharcada de escasa profundidad sometida a exposición subaérea y localizada en zonas aluviales distales. El yacimiento se incluye en la UTS N1 T5 y se propone una edad Mioceno inferior como lo más probable. Se han identificado ocho icnitas de grandes dimensiones y bajo grado de preservación morfológica, no reconociéndose en su mayoría sus elementos anatómicos salvo con una excepción que muestra la presencia de dedos en posición anterior. Considerando su tamaño y forma, un mamífero de gran tamaño, posiblemente un perisodáctilo o un artiodáctilo, sería el productor más probable.

The Ribota site (Ágreda, Soria, Spain) is a new locality in the Matute Formation (Tithonian–Berriasian) composed of several carbonate layers, outstandingly rich in macrovertebrate remains. Fossils show an unusual replacement of the original bioapatite by quartz, and are found as positive reliefs protruding from lacustrine limestone beds. This type of conservation has allowed the identification of around one hundred vertebrate bone accumulations in an outcrop of more than 10 hectares. Osteichthyans (articulated partial skeletons, cranial material, and isolated postcranial bones and scales), crocodylomorphs (disarticulated cranial material, isolated teeth, vertebrae and osteoderms), turtles (partial carapaces and plastra, but also isolated plates) and pterosaurs (cranial and appendicular elements) have been identified. Around 80 specimens have been collected and a preliminary study of part of the collection (35 specimens) has allowed the identification of at least 5 different taxa: Halecomorphi indet., Neoginglymodi indet., Goniopholididae indet., Testudinata indet., and Pterodactyloidea indet. This new site represents one of the few sites from this time interval preserved in a fully lacustrine environment, so these vertebrate assemblages are unique and composed of different animals that presumably lived around and within the lake. They are dominated by aquatic and amphibian vertebrates and was formed by attrition in this lacustrine environment, possibly far from the lake shoreline. These macrovertebrate assemblages provide new data about the diversity in the faunal ecosystems from the Jurassic/Cretaceous transition of the Iberian Basin Rift System.

Studies of the paleopathology of the vertebrae provide an interesting, oblique approach to their paleobiology and even paleoethology. They tell us about possible ethological causes such as accidental blows with objects, social interactions within a group, and defense against predators, etc. There are numerous works on the anatomical and phylogenetic aspects of sauropod dinosaurs, and in recent years paleopathological studies have also increased. Here, we describe the injuries recorded in the caudal vertebrae of two indeterminate titanosaurids, and undertake a compilation and analysis of the pathological fossil record worldwide, focusing on the tails of sauropods. Two pathologies have been identified as present in the indeterminate titanosaurids under study: a possible case of spondyloarthropathy in MAU-Pv-LI-601, and a case of suppurative spinal osteomyelitis in MAU-Pv-LJ-472/1. Both titanosaurids are from Gondwana. In the world registry of pathologies associated with the tails of sauropod dinosaurs, it is observed that titanosaurs are the sauropods with the highest percentage of diagnosed pathologies (69% including the two new records from the province of Neuquén) and that all of these have been described in Gondwanan specimens.