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Guillaume, A. R. D., Moreno-Azanza M., & Mateus O. (2022).  New species of Albanerpetontidae (Lissamphibia) from the Lourinhã Formation. XXXVII Jornadas SEP y V Congreso Ibérico de Paleontología. 94., Cuenca: ISBN 13: 978-84-09-44478-6 Abstractguillaume_et_al_2022_albanerpetontidae_jornadas_sep_cuenca_abstract_2022.pdf


Ferrari, L., Rotatori F. M., Camilo B., Moreno-Azanza M., & Mateus O. (2022).  New specimen of dryomorphan (Ornithischia, Iguanodontia) remains from the Upper Jurassic of Portugal. Abstract book of the XIX Annual Conference of the European Association of Vertebrate Palaeontologists, Benevento/Pietraroja, Italy, 27th June-2nd July 2022.. 61-62.: PalaeoVertebrata, Special Volume 1- 2022, 224. Doi: 10.18563/pv.eavp Abstractferrarietal_2022.pdf


Puértolas-Pascual, E., Serrano-Martínez A., Kuzmin I. T., & Mateus O. (2022).  Paleoneuroanatomía de Portugalosuchus, un cocodrilomorfo eusuquio del Cenomaniense de Portugal. XXXVII Jornadas SEP y V Congreso Ibérico de Paleontología. 153., Cuenca: ISBN 13: 978-84-09-44478-6 Abstractpuertolas-pascula_et_al_2022_portugalosuchus_jornadas_sep_cuenca_abstract_2022.pdf


Fernandes, A. E., Mateus O., Andres B., Polcyn M. J., Schulp A. S., Gonçalves A. O., & Jacobs L. L. (2022).  Pterosaurs from the Late Cretaceous of Angola. Diversity. 14, , Number 9 Abstractdiversity-14-00741.pdfWebsite

Here, we describe the first pterosaur remains from Angola, an assemblage of fourteen bones from the Lower Maastrichtian marine deposits of Bentiaba, Namibe Province. One new species is introduced, Epapatelo otyikokolo, gen. et sp. nov., which comprises an articulated partial left humerus and ulna as well as an articulated left ulna and radius (from a second individual). Phylogenetic analysis confirms a non-nyctosaurid pteranodontian attribution for this new taxon and supports a new apomorphy-based clade, Aponyctosauria, which is here defined. Late Cretaceous pteranodontians are rare in Sub-Saharan Africa and throughout the Southern Hemisphere. Preliminary histological analysis also reveals a likely sub-adult age for one of the specimens. This fossil assemblage provides a first glimpse of Angolan pterosaur paleobiodiversity providing further insight into the Gondwanan ecosystems of the Upper Cretaceous.

Guillaume, A. R. D., Costa F., & Mateus O. (2022).  Stegosaur tracks from the Upper Jurassic of Portugal: new occurrences and perspectives. Ciências da Terra / Earth Sciences Journal. 20(1), 37-60. Abstractguillaumeetal.pdf

The record of Late Jurassic stegosaur tracks from the Lourinhã Formation (Kimmeridgian-Tithonian) is here revised. Thirty-eight dinosaur tracks, preserved as natural infill casts, are here reported, and thirty-two of them are attributed to the ichnogenus Deltapodus. Four of those present impressions of skin, with polygonal scales and random pattern. Deltapodus is the most common ichnogenus in the track record of the Lourinhã Formation. The sizes and shape suggest one single dacentrurine trackmaker, which could be Miragaia longicollum, also common in the same horizons.

Martino, R., Ríos M. I., Mateus O., & Pandolfi L. (2022).  Taxonomy, chronology, and dispersal patterns of Western European Quaternary hippopotamuses: New insight from Portuguese fossil material. Quaternary International. Abstractmartino_et_al_2022_hippos_portugal.pdfWebsite

The taxonomy, chronology and dispersal patterns of hippopotamuses in Western Europe are still a matter of debate, despite the long history of researchers on these topics. In this framework, the Portuguese material has never been investigated or recently revised, and it can contribute to increasing our comprehension about Quaternary hippopotamuses. The material considered in this work, collected from sites dated between 1 Ma and 0.13 Ma, is compared with fossil Pleistocene hippopotamuses from the Iberian Peninsula, Italy, Germany and Greece, in order to contribute into the discussion on evolutionary and dispersal patterns of these large semi-aquatic mammals in Europe during the Pleistocene. Portugal deposits recorded the presence of H. antiquus, starting from 1 Ma up to 0.4 Ma, and H. cf. amphibius during the late Middle Pleistocene. In particular, the occurrence of H. antiquus in Condeixa, dated around 0.4 Ma, can be considered as the LAD of this species in Europe. The paleobiogeography and dispersal patterns of European hippopotamuses are further discussed.

Mateus, O., Estraviz López D., & Madeira Mateus S. G. (2022).  Type specimens alone have a strong correlation with taxa record by geological epoch: the case study of the fossil vertebrates named from {Portuguese} types. Comunicações Geológicas. 109, 57–64. Abstractmateus-et-al_2022_type_specimens.pdfWebsite

ABSTRACT: Type specimens (holotypes, neotypes, syntypes, etc.) are of crucial importance because they are the only tangible evidence of the nomenclatural act that supports the understanding of paleobiodiversity. The list of the vertebrate species whose type specimen is based on fossils from Portugal is presented here. We counted 206 species, of which there are 45 bony fishes, 39 Late Jurassic Mammaliamorpha, 33 Cenozoic mammals, 28 non-avian dinosaurs, 25 non-dinosaur reptiles, 11 Cenozoic Aves, 22 Chondrichthyes and three other vertebrates. Except for the Quaternary fossil record, the type specimens can be used as a shortcut for measuring the fossil record and paleobiodiversity through geological time and rock units because they correlate in 95% with the fossil record by epoch in the case-study of fossil vertebrates of Portugal.

Moreno-Azanza, M., Balauz B., Ezquerro L., Coimbra R., Mateus O., & Nuñez-Lahuerta C. (2022).  Unbroken dinosaur eggs accumulated together do not guarantee autochthony of the fossil assemblage. Journal of Taphonomy. 16(1-4), 129-130. Abstractmoreno-azanza_et_al_2020_unbroken_eggs.pdf


Mateus, O., & Estraviz-López D. (2022).  A new theropod dinosaur from the early cretaceous (Barremian) of Cabo Espichel, Portugal: Implications for spinosaurid evolution. PLOS ONE. 17, 1-48., 02, Number 2: Public Library of Science Abstractjournal.pone_.0262614.pdfWebsite

Spinosaurids are some of the most enigmatic Mesozoic theropod dinosaurs due to their unique adaptations to aquatic environments and their relative scarcity. Their taxonomy has proven to be especially problematic. Recent discoveries from Western Europe in general, specifically Iberia, provide some of the best specimens for the understanding of their phylogeny, leading to the description of the spinosaurid Vallibonavenatrix cani and the recognition of the Iberian dinosaur Camarillasaurus cirugedae as one of them. Portuguese associated spinosaurid remains (ML1190) from the Papo Seco Formation (early Barremian) were previously assigned to Baryonyx walkeri but new material recovered in 2020 along with new phylogenetic analyses suggests a different phylogenetic placement, making their revision necessary. Here we show that these remains are not attributable to Baryonyx walkeri, but to a new genus and species, Iberospinus natarioi, gen. et sp. nov. The new taxon is characterized by the presence of a single Meckelian foramen in the Meckelian sulcus, a straight profile of the ventral surface of the dentary and a distal thickening of the acromion process of the pubis between other characters. Iberospinus natarioi is recovered as a sister taxon of the clade formed by Baryonyx and Suchomimus, and outside Spinosaurinae when Vallibonaventrix cani is excluded from the analysis. The description of this taxon reinforces Iberia as a hotspot for spinosaur biodiversity, with several endemic taxa for the region. As expected for the clade, the dentary displays a highly vascularized neurovascular network. The morphometric analysis of parts of the skeleton (pedal phalanx and caudal vertebrae, among others) shows an intermediate condition between basal tetanurans and spinosaurines.

Rotatori, F. M., Moreno-Azanza M., & Mateus O. (2022).  Reappraisal and new material of the holotype of Draconyx loureiroi (Ornithischia: Iguanodontia) provide insights on the tempo and modo of evolution of thumb-spiked dinosaurs. Zoological Journal of the Linnean Society. , 02 Abstractrotatori_etal2022.pdfWebsite

{The Upper Jurassic Lourinhã Formation is well known for its rich assemblage of fossil vertebrates. In this formation, ornithopod dinosaurs are represented by two iguanodontian species, Eousdryosaurus nanohallucis and Draconyx loureiroi. We recently became aware of unreported material belonging to the holotype of Draconyx loureiroi, consisting of partially articulated manual elements. We here re-describe the holotype specimen ML 357, including the newly discovered material. The specimen was subjected to CT-scanning and its surface data used to assess anatomical characters. Linear measurements of metatarsal III were used to estimate the body length of the specimen. The Draconyx loureiroi holotype was included in two datasets and analysed with maximum parsimony and Bayesian inference approaches to estimate evolutionary rates among Iguanodontia. We present evidence that Draconyx loureiroi is a valid taxon nested in Styracosterna and is clearly diagnosable by a unique combination of characters. Both maximum parsimony and Bayesian inference indicate high evolutionary rates across the Jurassic/Cretaceous transition for the base of Iguanodontia. Length estimation suggests that Draconyx loureiroi was a relatively small, bipedal and possibly cursorial animal. Given its basal phyletic position, we interpret this bauplan was the ancestral condition for Styracosterna, that only later in the Cretaceous evolved into giant quadrupedal forms.}

Conti, S., Tschopp E., Mateus O., Zanoni A., Masarati P., & Sala G. (2022).  Multibody analysis and soft tissue strength refute supersonic dinosaur tail. 12(1), 19245., 2022 Abstractconti_et_al_2022._multibody_analysis_and_soft_tissue_strength_refute_supersonic_dinosaur_tail.pdfWebsite

Sauropod dinosaurs are well known for their massive sizes and long necks and tails. Among sauropods, flagellicaudatan dinosaurs are characterized by extreme tail elongation, which has led to hypotheses regarding tail function, often compared to a whip. Here, we analyse the dynamics of motion of a 3D model of an apatosaurine flagellicaudatan tail using multibody simulation and quantify the stress-bearing capabilities of the associated soft tissues. Such an elongated and slender structure would allow achieving tip velocities in the order of 30 m/s, or 100 km/h, far slower than the speed of sound, due to the combined effect of friction of the musculature and articulations, as well as aerodynamic drag. The material properties of the skin, tendons, and ligaments also support such evidence, proving that in life, the tail would not have withstood the stresses imposed by travelling at the speed of sound, irrespective of the conjectural ‘popper’, a hypothetical soft tissue structure analogue to the terminal portion of a bullwhip able to surpass the speed of sound.

Guillaume, A. R. D., Natário C., Mateus O., & Moreno-Azanza M. (2022).  Plasticity in the morphology of the fused frontals of Albanerpetontidae (Lissamphibia; Allocaudata). Historical Biology. 1 - 18., 2022: Taylor & Francis Abstractplasticity_in_the_morphology_of_the_fused_frontals_of_albanerpetontidae_lissamphibia_allocaudata.pdfWebsite

ABSTRACTAlbanerpetontidae form an enigmatic extinct group of lissamphibians, ranging from the early Bathonian to the early Pleistocene. The Upper Jurassic outcrops of Portugal yield a large collection of material, suitable for addressing the intraspecific variation in and diagnostic potential of the characteristic fused frontals. We revise 58 specimens from the Guimarota beds of the Kimmeridgian Alcobaça Formation and describe 62 new frontal bones from the Kimmeridgian ? Tithonian Lourinh? Formation. Smaller specimens exhibit a vermicular dorsal ornamentation, while it is polygonal in larger specimens and other albanerpetontids. Compared to small specimens, larger specimens display: (1) larger ventrolateral crests extending posteriorly after the parietal margin; (2) a relatively shorter internasal process; (3) a frontal width across posterior edges relatively smaller; and (4) a ventromedian crest less pronounced. Morphometric analyses suggest a single species with different ontogenetic stages. Specimens are attributed to aff. Celtedens sp., based on a bell-shaped outline with a curved orbital margin (although variable in Portuguese specimens), and a flabellate, bulbous-shaped internasal process. The species is more similar to C. megacephalus than C. ibericus, but its phylogenetic position comprises an unresolved trichotomy. Our results show that intraspecific variation and homoplasy render the fused frontal non-diagnostic below the generic level.

Jacobs, L. L., Polcyn M. J., Mateus O., & Schulp A. S. (2023).  Deep time conservation paleobiology of the Atlantic jigsaw puzzle and the future of the southwestern Angolan coast. Bulletin of the Florida Museum of Natural History. 60(2), 90.: In: Abstracts of the 2nd Conservation Paleobiology Symposium. https://doi … Abstractjacobs_et_al_2023_jigsaw.pdf


Puértolas-Pascual, E., Kuzmin I. T., Serrano-Martínez A., & Mateus O. (2023).  Neuroanatomy of the crocodylomorph Portugalosuchus azenhae from the late cretaceous of Portugal. Journal of Anatomy. n/a, , Number n/a Abstractjournal_of_anatomy_-_2023_-_pu_rtolas-pascual_-_neuroanatomy_of_the_crocodylomorph_portugalosuchus_azenhae_from_the_late.pdfWebsite

Abstract We present the first detailed braincase anatomical description and neuroanatomical study of Portugalosuchus azenhae, from the Cenomanian (Late Cretaceous) of Portugal. This eusuchian crocodylomorph was originally described as a putative Crocodylia and one of the oldest representatives of this clade; however, its phylogenetic position remains controversial. Based on new data obtained from high resolution Computed Tomography images (by micro-CT scan), this study aims to improve the original description of this taxon and also update the scarce neuroanatomical knowledge of Eusuchia and Crocodylia from this time interval, a key period to understand the origin and evolution of these clades. The resulting three-dimensional models from the CT data allowed a detailed description of its well-preserved neurocranium and internal cavities. Therefore, it was possible to reconstruct the cavities of the olfactory region, nasopharyngeal ducts, brain, nerves, carotid arteries, blood vessels, paratympanic sinus system and inner ear, which allowed to estimate some neurosensorial capabilities. By comparison with other crocodylomorphs, these analyses showed that Portugalosuchus, back in the Cenomanian, already displayed an olfactive acuity, sight, hearing and cognitive skills within the range of that observed in other basal eusuchians and crocodylians, including extant species. In addition, and in order to test its disputed phylogenetic position, these new anatomical data, which helped to correct and complete some of the original observations, were included in one of the most recent morphology-based phylogenies. The position of Portugalosuchus differs slightly from the original publication since it is now located as a “thoracosaurid” within Gavialoidea, but still as a crocodylian. Despite all this, to better contrast these results, additional phylogenetic analyses including this new morphological character coding together with DNA data should be performed.

Conti, S., Sala G., & Mateus O. (2023).  Smart Biomechanical Adaptation Revealed by the Structure of Ostrich Limb Bones. Biomimetics. 8(1), , Number 1 Abstractbiomimetics-08-00098.pdfWebsite

Ostriches are known to be the fastest bipedal animal alive; to accomplish such an achievement, their anatomy evolved to sustain the stresses imposed by running at such velocities. Ostriches represent an excellent case study due to the fact that their locomotor kinematics have been extensively studied for their running capabilities. The shape and structure of ostrich bones are also known to be optimized to sustain the stresses imposed by the body mass and accelerations to which the bones are subjected during movements. This study focuses on the limb bones, investigating the structure of the bones as well as the material properties, and how both the structure and material evolved to maximise the performance while minimising the stresses applied to the bones themselves. The femoral shaft is hollowed and it presents an imbricate structure of fused bone ridges connected to the walls of the marrow cavity, while the tibial shaft is subdivided into regions having different mechanical characteristics. These adaptations indicate the optimization of both the structure and the material to bear the stresses. The regionalization of the material highlighted by the mechanical tests represents the capability of the bone to adapt to external stimuli during the life of an individual, optimizing not only the structure of the bone but the material itself.

López-Rojas, V., Clemmensen L. B., Milàn J., Wings O., Klein N., & Mateus O. (2023).  A new phytosaur species (Archosauriformes) from the Upper Triassic of Jameson Land, central East Greenland. Journal of Vertebrate PaleontologyJournal of Vertebrate Paleontology. e2181086., 2023: Taylor & Francis Abstracta_new_phytosaur_species_archosauriformes_from_the_upper_triassic_of_jameson_land_central_east_greenland.pdfWebsite

ABSTRACTHerein we describe phytosaurs from thin fluvial overbank sandstones of the Upper Triassic Malmros Klint Formation of the Fleming Fjord Group (central East Greenland). The new sample includes more than 150 disarticulated bones and teeth from small to large specimens belonging to at least four individuals. The fossils mostly consist of teeth and postcranial elements and permit the recognition of a new species of Mystriosuchus, M. alleroq, diagnosed by an L-shaped quadratojugal whose anterior suture trends anterodorsally and a tripartite degree of heterodonty. Humeral diaphyseal histology of one specimen reveals a fairly compact cortex that surrounds a cancellous medullary region followed by a remodeling zone containing scattered secondary osteons. Primary bone tissue is parallel-fibred with a moderate to low vascular density. The cortex is cyclically interrupted by distinct growth marks indicating a seasonal environment. A change in growth rate from moderate to low is documented within the outer cortex, indicating that at least this individual was close to somatic maturity. Mystriosuchus has formerly been known as an exclusively European taxon. The new findings support the European faunal influence in East Greenland during the Late Triassic inferred from other taxa such as temnospondyls and archosaurs. The mid-late Norian age of European Mystriosuchus suggests an additional age constraint for the vertebrate-bearing portion of the Malmros Klint Formation.