Postcranial elements of "Maledictosuchus riclaensis" (Thalattosuchia) from the Middle Jurassic of Spain

Maledictosuchus riclaensis is a metriorhynchid crocodylomorph from the Callovian (Middle Jurassic) of Ricla (Spain). It is the most basal member of the Rhacheosaurini Tribe; it has recently been described and defined by its cranial elements (an almost complete skull and part of the lower jaw), but there were no data on the postcranial elements. Associated with the skull three vertebrae were collected. These vertebrae were preserved in black calcite nodules, and they have recently been prepared. The postcranial elements of the metriorhynchids are poorly documented, and usually badly preserved or included in the matrix. Herein we describe the three vertebrae (part of the holotype) of M. riclaensis. These comprise one cervical, one dorsal and one caudal vertebra, which, like the skull, are well preserved and lack postmortem distortion or deformation.Maledictosuchus riclaensis es un crocodilomorfo metriorrínquido del Calloviense (Jurásico medio) de Ricla (España). Es el miembro más basal de la tribu de los raqueosaurinos, y ha sido definido a partir de sus elementos craneales (un cráneo prácticamente completo y parte de la mandíbula inferior). Sin embargo no había datos de los elementos poscraneales. Durante la campaña de prospección en la que se recuperó el holotipo, se recuperaron tres vértebras asociadas al cráneo. Las vértebras estaban preservadas en nódulos de calcita, y han sido preparadas recientemente. Los elementos poscraneales de los metriorrínquidos están poco documentados, y normalmente, mal preservados o incluidos en la matriz. En este trabajo se hace descripción de tres vértebras, cervical, dorsal y caudal, del ejemplar tipo de M. riclaensis

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

A new rebbachisaurid sauropod from the Aptian–Albian, Lower Cretaceous Rayoso Formation, Neuquén, Argentina

Rebbachisaurids are a group of basal diplodocimorph sauropods that diversified in Gondwana at the end of the Early Cretaceous and the beginning of the Late Cretaceous. It is a group of great palaeobiogeographical interest, for it clearly illustrates various processes of dispersal throughout Gondwana and to Laurasia prior to the breakup of Africa and South America. However, the relationships within the group are still under discussion owing to the scarcity of cranial material that would help clarify them. In the present paper we describe the new rebbachisaurid Lavocatisaurus agrioensis gen. et sp. nov. from the Aptian–Albian (Lower Cretaceous) of Neuquén (Argentina). Remains have been recovered belonging to an adult specimen (holotype) and two immature specimens (paratypes). Taken together, almost all the bones of the taxon are represented, including most of the cranium. Lavocatisaurus agrioensis gen. et sp. nov. is the first rebbachisaurid from Argentina with an almost complete cranium, making it possible to recognize differences with respect to other rebbachisaurids, such as the highly derived Nigersaurus. Among its most notable characters are the presences of a large preantorbital fenestra and maxillary teeth that are significantly larger than those of the dentary. Our phylogenetic study places Lavocatisaurus amongst basal rebbachisaurids, as the sister lineage to Khebbashia (the clade formed by Limaysaurinae + Rebbachisaurinae). This position, which is somewhat more derived than that previously suggested for Comahuesaurus and Zapalasaurus (the Argentinean rebbachisaurids closest in geographical and geological terms), reaffirms the presence of different basal rebbachisaurid lineages in the Early Cretaceous of Patagonia

The First Metriorhynchid Crocodylomorph from the Middle Jurassic of Spain, with Implications for Evolution of the Subclade Rhacheosaurini

Background: Marine deposits from the Callovian of Europe have yielded numerous species of metriorhynchid crocodylomorphs. While common in English and French Formations, metriorhynchids are poorly known from the Iberian Peninsula. Twenty years ago an incomplete, but beautifully preserved, skull was discovered from the Middle Callovian of Spain. It is currently the oldest and best preserved metriorhynchid specimen from the Iberian Peninsula. Until now it has never been properly described and its taxonomic affinities remained obscure. Methodology/Principal Findings: Here we present a comprehensive description for this specimen and in doing so we refer it to a new genus and species: Maledictosuchus riclaensis. This species is diagnosed by numerous autapomorphies, including: heterodont dentition; tightly interlocking occlusion; lachrymal anterior process excludes the jugal from the preorbital fenestra; orbits longer than supratemporal fenestrae; palatine has two non-midline and one midline anterior processes. Our phylogenetic analysis finds Maledictosuchus riclaensis to be the basal-most known member of Rhacheosaurini (the subclade of increasingly mesopelagic piscivores that includes Cricosaurus and Rhacheosaurus). Conclusions/Significance: Our description of Maledictosuchus riclaensis shows that the craniodental morphologies that underpinned the success of Rhacheosaurini in the Late Jurassic and Early Cretaceous, as a result of increasing marine specialization to adaptations for feeding on fast small-bodied prey (i.e. divided and retracted external nares; reorientation of the lateral processes of the frontal; elongate, tubular rostrum; procumbent and non-carinated dentition; high overall tooth count; and dorsolaterally inclined paroccipital processes), first appeared during the Middle Jurassic. Rhacheosaurins were curiously rare in the Middle Jurassic, as only one specimen of Maledictosuchus riclaensis is known (with no representatives discovered from the well-sampled Oxford Clay Formation of England). As such, the feeding/marine adaptations of Rhacheosaurini did not confer an immediate selective advantage upon the group, and it took until the Late Jurassic for this subclade to dominate in Western Europe

Bioerosion and palaeoecological association of osteophagous insects in the Maastrichtian dinosaur Arenysaurus ardevoli

Bioerosions produced by the osteophagous diet of animals that fed on dinosaur bones are very scarce in the European fossil record. Herein we present bioerosion on hadrosaurid remains from the Maastrichtian Tremp Formation of the Pyrenean Basin, which is only the second such case recorded from the Iberian-Occitan Plate besides a sauropod from the Jurassic-Cretaceous of Valencia. The hadrosaurid fossil record is particularly rich in the Blasi sites of the Tremp Formation located in the municipality of Arén (Huesca, Spain). In this article, bones referred to the hadrosaurid Arenysaurus ardevoli from the Blasi-3 site are analysed to shed light on the palaeoenvironment and on the presence of a palaeoecological interaction between the hadrosaurid carcase and osteophagous tracemakers. Bioerosions recorded on the bones comprise tunnels, roundish holes, and straight notches, similar to the traces attributed to necrophagous insects (cf. Cuniculichnus seilacheri). Here, we record the first instance of the activity of these animals on dinosaur bones in the Upper Cretaceous of the Ibero-Occitan Plate. The results presented lead us to infer that the Arenysaurus bones were possibly transported by a storm or similar event to the Blasi-3 site, where they were exposed to post-mortem biotic interactions (eaten and partially decomposed by dermestid beetles) for a prolonged time period before they were completely buried. © 2021 The Authors. Lethaia published by John Wiley & Sons Ltd on behalf of Lethaia Foundatio

Determination of lanthanides in fossil samples using laser induced breakdown spectroscopy

As being a fast, simple and relatively non-destructive analytical technique Laser-induced breakdown spectroscopy (LIBS) has a large variety of applications including the analysis of paleontological samples. In this work LIBS is employed for the quantitative determination of lanthanides (Ce, Dy, Er, Eu, Gd, Ho, La, Lu, Nd, Sm, Tb, Tm and Yb) in vertebrate fossil samples comprising teeth, disarticulated complete or fragmented bones, eggshell fragments, and coprolites of dinosaurs, mammals and crocodiles. For emission line data, standard AnalaR grade salts of lanthanides were used. The major components: Iron, calcium, magnesium, silicon and aluminum in the samples were also determined. The analytical information may be helpful in studying the samples for their age, formation environment and other paleontological properties

Europatitan eastwoodi, a new sauropod from the lower Cretaceous of Iberia in the initial radiation of somphospondylans in Laurasia

The sauropod of El Oterillo II is a specimen that was excavated from the Castrillo de la Reina Formation (Burgos, Spain), late Barremian-early Aptian, in the 2000s but initially remained undescribed. A tooth and elements of the axial skeleton, and the scapular and pelvic girdle, represent it. It is one of the most complete titanosauriform sauropods from the Early Cretaceous of Europe and presents an opportunity to deepen our understanding of the radiation of this clade in the Early Cretaceous and study the paleobiogeographical relationships of Iberia with Gondwana and with other parts of Laurasia. The late Barremian-early Aptian is the time interval in the Cretaceous with the greatest diversity of sauropod taxa described in Iberia: two titanosauriforms, Tastavinsaurus and Europatitan; and a rebbachisaurid, Demandasaurus. The new sauropod Europatitan eastwoodi n. gen. n. sp. presents a series of autapomorphic characters in the presacral vertebrae and scapula that distinguish it from the other sauropods of the Early Cretaceous of Iberia. Our phylogenetic study locates Europatitan as the basalmost member of the Somphospondyli, clearly differentiated from other clades such as Brachiosauridae and Titanosauria, and distantly related to the contemporaneous Tastavinsaurus. Europatitan could be a representative of a Eurogondwanan fauna like Demandasaurus, the other sauropod described from the Castrillo de la Reina Formation. The presence of a sauropod fauna with marked Gondwananan affinities in the Aptian of Iberia reinforces the idea of faunal exchanges between this continental masses during the Early Cretaceous. Further specimens and more detailed analysis are needed to elucidate if this Aptian fauna is caused by the presence of previously unnoticed Aptian land bridges, or it represents a relict fauna from an earlier dispersal event

Presence of diminutive hadrosaurids (Dinosauria: Ornithopoda) in the Maastrichtian of the south-central Pyrenees (Spain)

In recent years a rich and diverse fauna of hadrosaurid dinosaurs has been described in the Upper Cretaceous of the Pyrenees. Recent fieldwork carried out in the upper Maastrichtian levels of the Tremp Formation, in the south-central Pyrenees (province of Huesca, northeastern Spain), has allowed us to recover diminutive fossil bones referable to hadrosaurid dinosaurs. To date, small-sized specimens had not been reported in the area. The remains consist of small vertebrae and fragmentary long bones found in a relatively small area, so it is assumed that they probably belong to individuals of a single population. A morphological examination and a histological study reveal that they represent specimens of advanced ontogenetic stage and allow the identification of an undescribed taxon of small-bodied hadrosaurids. In other parts of Europe, discoveries of small dinosaurs have been linked to insularity. These findings bring to light the smallest hadrosaurid known in Europe to date.This paper forms part of the projects CGL2010-16447, CGL2010-18851/BTE and CGL2013-47521-P, subsidized by the Spanish Ministerio de Economia y Competitividad and the European Regional Development Fund. In addition the Government of Aragon ("Grupos Consolidados'' and "Direccion General de Patrimonio Cultural'') has subsidized the fieldwork. The second author received a postdoctoral grant from the Ministerio de Ciencia, Tecnologia e Innovacion Productiva del Consejo Nacional de Investigaciones Cientificas y Tecnicas (CONICET). The study of the specimens housed at the NHM (London) has been suported by a study grant funded by the Caja de Ahorros de la Inmaculada (Zaragoza) to the second author in 2006. The manuscript has greatly benefited from reviews by Edina Prondvai (MTA-ELTE Lendulet Dinosaur Research Group, Budapest) and David B. Weishampel (Johns Hopkins University - School of Medicine, Baltimore). Special thanks also are owed to J.I. Ruiz-Omenaca (Museo Jurasico de Asturias-MUJA, Colunga) and Xabier Pereda-Suberbiola (Universidad del Pais Vasco, UPV/EHU, Bilbao) for providing helpful information on Nopcsa's work. Rupert Glasgow corrected the English text.Company Rodríguez, J.; Cruzado Caballero, P.; Canudo, J. (2015). Presence of diminutive hadrosaurids (Dinosauria: Ornithopoda) in the Maastrichtian of the south-central Pyrenees (Spain). Journal of Iberian Geology. 41(1):71-81. doi:10.5209/rev_JIGE.2015.v41.n1.48656718141

Glándulas de la sal en Maledictosuchus riclaensis (Metriorhynchidae, Thalattosuchia) del Calloviense de la Península Ibérica.

Maledictosuchus riclaensis es un metriorrínquido del Calloviense de la Península Ibérica. Los metriorrinquidos son un grupo de crocodilomorfos marinos que desarrollaron numerosas adaptaciones al medio marino pelágico. Además de adaptaciones morfológicas, desarrollaron glándulas de la sal hipertrofiadas, lo cual implica un alto grado de especialización. Estas glándulas se han descrito en dos especies de metriorrínquidos. Las glándulas de la sal se encargan de controlar el balance de la concentración de sales en el organismo. Al tratarse de tejidos blandos su preservación es muy poco frecuente. La tomo- grafía computarizada ha alcanzado en los últimos años gran importancia en la investigación paleontológica, ya que permite la visualización y estudio de las estructuras internas de los huesos y su digitalización en 3D, de una forma no invasiva y sin poner en riesgo al ejemplar. El holotipo de Maledictosuchus riclaensis consiste en un cráneo muy bien preservado y tres vértebras. Una tomografía computarizada del cráneo reveló la presencia de glándulas de la sal hipertrofiadas en este taxón

Primera evidencia de dinosaurios ornitópodos en la base de la Formación Huincul (Cenomaniense Superior-Turoniense, Cuenca Neuquina, Argentina)

Se describe por primera vez la presencia de dinosaurios ornitópodos en la base de la Formación Huincul (Cenomaniense-Turoniense) de Agrio del Medio (Neuquén, Argentina). Se trata de una falange ungueal del pie bien conservada y de pequeño tamaño. Presenta una morfología general en forma de garra, similar a la de los ornitópodos basales que se han encontrado en el Cretácico Superior de Sudamérica, lo que le diferencia de las formas más derivadas de iguanodontios con ungueal en forma de casco. Este descubrimiento es una nueva evidencia que los pequeños ornitópodos basales se encontraban en la Cuenca Neuquina, al menos, desde el transito Cretácico Inferior-Superior. We describe for the first time the presence of ornithopod dinosaurs at the base of the Huincul Formation (Cenomanian-Turonian) of Agrio del Medio (Neuquén, Patagonia, Argentina). The specimen in question is a well-preserved and small phalanx toenail. It presents a general morphology in the form of a claw, similar to that of basal ornithopods that have been found in the Upper Cretaceous of South America. This differentiates it from the most derived iguanodontians, which have a hoof-shaped nail. This finding is new evidence than indicates that small basal ornithopods were in the Neuquén Basin at least since the transition of the Early-Late Cretaceous