Publications

Export 688 results:
Sort by: Author Title [ Type  (Asc)] Year
Journal Article
Strganac, C., Jacobs L., Polcyn M., Mateus O., Myers T., Araújo R., Fergunson K. M., Gonçalves A. O., Morais M. L., Schulp A. S., da Tavares T. S., & Salminen J. (2015).  Geological Setting and Paleoecology of the Upper Cretaceous Bench 19 Marine Vertebrate Bonebed at Bentiaba, Angola. Netherlands Journal of Geosciences. 94(1), 121-136. Abstractstrganac_et_al_2014_geological_setting_bentiaba_angola.pdfWebsite

The Bench 19 Bonebed at Bentiaba, Angola, is a unique concentration of marine vertebrates preserving six species of mosasaurs in sediments best correlated by magnetostratigraphy to chron C32n.1n between 71.4 and 71.64 Ma. The bonebed formed at a paleolatitude near 24°S, with an Atlantic width at that latitude approximating 2700 km, roughly half that of the current width. The locality lies on an uncharacteristically narrow continental shelf near transform faults that controlled the coastal outline of Africa in the formation of the South Atlantic Ocean. Biostratigraphic change through the Bentiaba section indicates that the accumulation occurred in an ecological time dimension within the 240 ky bin delimited by chron 32n.1n. The fauna occurs in a 10 m sand unit in the Mocuio Formation with bones and partial skeletons concentrated in, but not limited to, the basal 1–2 m. The sediment entombing the fossils is an immature feldspathic sand shown by detrital zircon ages to be derived from nearby granitic shield rocks. Specimens do not appear to have a strong preferred orientation and they are not concentrated in a strand line. Stable oxygen isotope analysis of associated bivalve shells indicates a water temperature of 18.5°C. The bonebed is clearly mixed with scattered dinosaur and pterosaur elements in a marine assemblage. Gut contents, scavenging marks and associated shed shark teeth in the Bench 19 Fauna indicate biological association and attrition due to feeding activities. The ecological diversity of mosasaur species is shown by tooth and body-size disparity and by δ13C analysis of tooth enamel, which indicate a variety of foraging areas and dietary niches. The Bench 19 Fauna was formed in arid latitudes along a coastal desert similar to that of modern Namibia on a narrow, tectonically controlled continental shelf, in shallow waters below wave base. The area was used as a foraging ground for diverse species, including molluscivorus Globidens phosphaticus, small species expected near the coast, abundant Prognathodon kianda, which fed on other mosasaurs at Bench 19, and species that may have been transient and opportunistic feeders in the area.

Strganac, C., Jacobs L. L., Polcyn M. J., Mateus O., Myers T. S., Salminen J., May S. R., Araújo R., Ferguson K. M., Gon?alves A. O., Morais M. L., Schulp A. S., & da Silva Tavares T. (2014).  Geological setting and paleoecology of the Upper Cretaceous Bench 19 Marine Vertebrate Bonebed at Bentiaba, Angola. Geologie en Mijnbouw/Netherlands Journal of Geosciences. 94, 121-136., Number 1 Abstract
n/a
Polcyn, M., Jacobs L., Strganac C., Mateus O., Myers S., May S., Araujo R., Schulp A., & Morais M. (2014).  Geology and paleoecology of a marine vertebrate bonebed from the lower Maastrichtian of Angola. Journal of Vertebrate Paleontology. Program and Abstracts, 2014, 206.polcyn_et_al._2014_geology_and_paleoecology_of_a_marine_vertebrate_bonebed_from_the_lower_maastrichtian_of_angola.pdf
Hayashi, S., Redelstorff R., Mateus O., Watabe M., & Carpenter K. (2014).  Gigantism of stegosaurian osteoderms. Journal of Vertebrate Paleontology. Program and Abstracts, 2014, 145.hayashi_et_al_2014_gigantism_of_stegosaurian_osteoderms.pdf
Mateus, O. (2014).  Gigantism of stegosaurian osteoderms. Journal of Vertebrate Paleontology. Program and Abstracts, 2014, 145.: Taylor & Francis Abstract
n/a
Rotatori, F. M., Quaranta M., Bertozzo F., Hübner T., Camilo B., Mateus O., & Moreno-Azanza M. (2023).  Hadrosaur-like vascularisation in the dentary of an early diverging iguanodontian dinosaur. Historical Biology. 1-6.: Taylor & Francis AbstractWebsite

ABSTRACTVirtual palaeontology is a growing field, leading palaeontologists to better understand the microanatomy of many extinct species. The application of techniques such as CT and μCT-scanning allows the researchers to study micro-anatomical features in a non-invasive way and make inferences on the palaeobiology of animals. Dinosaurs have been extensively studied using these techniques, with particular focus on the microanatomy of the cranium, whereas relatively little is known of other cranial elements, such as the lower jaw. Here, we aim to fill this gap, describing the microanatomy of the specimen ML 768, an isolated dentary belonging to a dryosaurid iguanodontian dinosaur from the Upper Jurassic of Lourinhã Fm. The dentary ML 768 was subjected to μCT-scanning, and subsequently the data were segmented in Avizo and rendered in Blender. We identified functional and replacement teeth, recognising remnants of old replacement cycles. Furthermore, we mapped a rich neurovascular network present in the dentary and compared it with reference literature. We found that the high vascularisation is shared with other cerapodan dinosaurs with high tooth replacement rates, although homoeostasis may have also played a role in the development of this condition. Further evidence is needed to appreciate the macroevolutionary significance of these findings.

Polcyn, M., Jacobs L., Schulp A., & Mateus O. (2007).  Halisaurus (Squamata: Mosasauridae) from the Maastrichtian of Angola. Journal of Vertebrate Paleontology. 27(Suppl. to 3), 130A., Jan: Museu Lourinha, So Methodist Univ, Nat Hist Museum Maastricht Abstractpolcyn_et_al_mateus2007_halisaurus_angola_svpmeet.pdf

Recent fieldwork in the Namibe province in southern Angola yielded cranial and postcranial elements of at least two individuals of the rare and enigmatic mosasaur Halisaurus from a single small excavation. The genus Halisaurus is unique in retaining a primitive configuration of the temporal arcade, specifically a broad, vertically oriented contact between the parietal and the supratemporal. The supratemporal is broadly sutured to the opisthotic and prootic, unlike the condition in varanoids in which the simple lunate element lies between the parietal ramus and the squamosal and does not form a sutural contact with the opisthotic or prootic, but as in other halisaurines retains a plesiomorphic, vertically oriented contact with the parietal rami. The squamosal is lightly built and broadly arched as in Varanus. Comparison with known halisaurines indicates the new material is referable to the species Halisaurus arambourgi.
The locality that yielded the new specimens has also yielded a large number of isolated teeth, bones, articulated, and associated skeletons of Mosasaurus, Prognathodon, Globidens, and Plioplatecarpus, which with Halisaurus comprise a mosasaur assemblage most similar to that reported from the Maastrichtian of Morocco.

Polcyn, M., Jacobs L. L., Schulp A., & Mateus O. (2007).  Halisaurus (Squamata: Mosasauridae) from the Maastrichtian of Angola. Journal of Vertebrate Paleontology. 27(suppl. to 3), 130. Abstract
n/a
de Ricqlès, A., Mateus O., Antunes M. T., & Taquet P. (2001).  Histomorphogenesis of embryos of Upper Jurassic Theropods from Lourinha (Portugal). Comptes Rendus De L Academie Des Sciences Serie Ii Fascicule a-Sciences De La Terre Et Des Planetes. 332, 647-656., Jan Abstractricqles_mateus_et_al_2011_histomorphogenesis_of_embryos_of_upper_jurassic_theropods_from_lourinha_portugal.pdfWebsite

Remains of dinosaurian embryos, hatchlings and early juveniles are currently the subject of increasing interest, as new discoveries and techniques now allow to analyse palaeobiological subjects such as growth and life history strategies of dinosaurs. So far, available ‘embryonic’ material mainly involved Ornithopods and some Theropods of Upper Cretaceous age. We describe here the histology of several bones (vertebrae, limb bones) from the tiny but exceptionally well preserved in ovo remains of Upper Jurassic Theropod dinosaurs from the Paimogo locality near Lourinhã (Portugal). This Jurassic material allows to extend in time and to considerably supplement in great details our knowledge of early phases of growth in diameter and in length of endoskeletal bones of various shape, as well as shape modelling among carnivorous dinosaurs. Endochondral ossification in both short and long bones involves extensive pads of calcified cartilages permeated by marrow buds. We discuss the likely occurrence of genuine cartilage canals in dinosaurs and of an avian-like ‘medullary cartilaginous cone’ in Theropods. Patterns of periosteal ossification suggest high initial growth rates (20 μ m·day−1 or more), at once modulated by precise and locally specific changes in rates of new bone deposition. The resulting very precise shape modelling appears to start early and to involve at once some biomechanical components.

de Ricqlès, A., Mateus O., Antunes M. T., & Taquet P. (2001).  Histomorphogenesis of embryos of Upper Jurassic Theropods from Lourinhã (Portugal). Comptes Rendus de l{\textquotesingle}Académie des Sciences - Series {IIA} - Earth and Planetary Science. 332, 647–656., may, Number 10: Elsevier {BV} AbstractWebsite
n/a
de Ricqlès, A., Mateus O., Antunes M. T., & Taquet P. (2001).  Histomorphogenesis of embryos of Upper Jurassic theropods from Lourinhã (Portugal). Comptes Rendus de l'Académie des Sciences-Series IIA-Earth and Planetary Science. 332, 647–656., Number 10 Abstract
n/a
de Ricqlès, A., Mateus O., Antunes M. T., & Taquet P. (2001).  Histomorphogenesis of embryos of Upper Jurassic theropods from Lourinhã (Portugal) | Histomorphogenèse du squelette d'embryons de dinosaures théropodes du Jurassique supérieur de Lourinhã (Portugal). Comptes Rendus de l'Academie de Sciences - Serie IIa: Sciences de la Terre et des Planetes. 332, 647–656., Number 10 Abstract
n/a
Mateus, O., & Milan J. (2008).  Ichnological evidence for giant ornithopod dinosaurs in the Upper Jurassic Lourinhã Formation, Portugal. Oryctos. 8, 47-52. Abstractmateus_and_milan_2008_ichnological_evidence_for_giant_ornithopod_big_ornithopod_track_from_u_j_lourinha_fm_portugal.pdfWebsite

The Upper Jurassic Lourinhã Formation (Lusitanian Basin, Portugal) contains a diverse dinosaur fauna comprising theropods, sauropods, stegosaurs, ankylosaurs and several genera of ornithopods. The sedimentology in the area favours preservation of tracksways, and tracks from most of the dinosaurs are also represented by skeletal remains. During fieldwork in the summer of 2003 a new, large, tridactyl track was found at the beach of Vale Frades, approximately 6 km north of Lourinhã (central west Portugal). The track was found together with a stegosaur track on a clay bed exposed within the intertidal zone. Due to the immediate danger of erosion, the track was collected and is now on display at Museu da Lourinhã. The track is 70 cm long and 69 cm wide, the toes are short and broad, with indications of short blunt claws, and there is a high angle of divarication between the outer digits. The shape and dimensions of the track identifies it as deriving from an ornithopod dinosaur with an estimated hip height around three metres. Although very large ornithopods are known from the Cretaceous, the largest known Jurassic ornithopod is Camptosaurus from North America, and the largest known from Portugal is the camptosaurid Draconyx loureiroi. Neither of these reached the body size suggested by the new track. So far the track described herein is the only evidence for a Jurassic ornithopod of that size.

Marzola, M., Russo J., & Mateus O. (2015).  Identification and comparison of modern and fossil crocodilian eggs and eggshell structures. Historical Biology. 27(1), 115-133. Abstractmarzola_et_al_2015_identification_and_comparison_of_modern_and_fossil_crocodilian_eggs_and_eggshell_structures.pdfWebsite

Eggshells from the three extant crocodilian species Crocodylus mindorensis (Philippine Crocodile), Paleosuchus palpebrosus (Cuvier's Smooth-fronted Caiman or Musky Caiman) and Alligator mississippiensis (American Alligator or Common Alligator) were prepared for thin section and scanning electron microscope analyses and are described in order to improve the knowledge on crocodilian eggs anatomy and microstructure, and to find new apomorphies that can be used for identification. Both extant and fossil crocodilian eggs present an ornamentation that vary as anastomo-, ramo- or the here newly described rugosocavate type. The angusticaniculate pore system is a shared character for Crocodylomorpha eggshells and some dinosaurian and avian groups. Previously reported signs of incubated crocodilian eggs were found also on our only fertilised and hatched egg. Paleosuchus palpebrosus presents unique organization and morphology of the three eggshell layers, with a relatively thin middle layer characterised by dense and compact tabular microstructure.

Marzola, M., Russo J., & Mateus O. (2015).  Identification and comparison of modern and fossil crocodilian eggs and eggshell structures. Historical Biology. 27, 115-133., Number 1 Abstract
n/a
Sander, M., Laven T., Mateus O., & Knotschke N. (2004).  Insular dwarfism in a brachiosaurid sauropod from the Upper Jurassic of Germany. Journal of Vertebrate Paleontology. 23, 108., Number Suppl. to 3 Abstract
n/a
Sander, M., Laven T., Mateus O., & Knotschke N. (2004).  Insular dwarfism in a brachiosaurid sauropod from the Upper Jurassic of Germany. Journal of Vertebrate Paleontology. 23, 108–108., Number Suppl. to Abstract
n/a
Beccari, V., Mateus O., Wings O., Milàn J., & Clemmensen L. B. (2021).  Issi saaneq gen. et sp. nov.—A New Sauropodomorph Dinosaur from the Late Triassic (Norian) of Jameson Land, Central East Greenland. Diversity. 13, , Number 11 Abstractdiversity-13-00561-v2.pdfWebsite

The Late Triassic (Norian) outcrops of the Malmros Klint Formation, Jameson Land (Greenland) have yielded numerous specimens of non-sauropod sauropodomorphs. Relevant fossils were briefly reported in 1994 and were assigned to Plateosaurus trossingensis. However, continuous new findings of early non-sauropod sauropodomorphs around the globe facilitate comparisons and allow us to now revise this material. Here, the non-sauropod sauropodomorph Issi saaneq gen. et sp. nov. is described based on two almost complete and articulated skulls. The two skulls represent a middle-stage juvenile and a late-stage juvenile or subadult. Issi saaneq differs from all other sauropodomorphs by several unique traits: (1) a small foramen at the medial surface of the premaxilla; (2) an anteroposteriorly elongated dorsoposterior process of the squamosal; (3) a relatively high quadrate relative to rostrum height; (4) a well-developed posterodorsal process of the articular. These features cannot be explained by taphonomy, ontogeny, or intraspecific variation. Issi saaneq shows affinities to Brazilian plateosaurids and the European Plateosaurus, being recovered as the sister clade of the latter in our phylogenetic analysis. It is the northernmost record of a Late Triassic sauropodomorph, and a new dinosaur species erected for Greenland. Issi saaneq broadens our knowledge about the evolution of plateosaurid sauropodomorphs.

Milan, J., & Mateus O. (2005).  Jagten på Europas største dinosaur.. Naturens Verden. 88(10), 2-13.. AbstractWebsite

[In danish. Title translation: The hunt for the biggest dinosaur in Europe]

Mateus, O., Walen A., & Antunes M. T. (2006).  The large theropod fauna of the Lourinhã Formation (Portugal) and its similarity to that of the Morrison Formation, with a description of new species of Allosaurus. New Mexico Museum of Natural History and Science Bulletin. 36, , Number 123-129 Abstract
n/a
Mateus, O., Walen A., & Antunes M. T. (2006).  The large theropod fauna of the Lourinhã Formation (Portugal) and its similarity to the Morrison Formation, with a description of a new species of Allosaurus. New Mexico Museum of Natural History and Science Bulletin. 36, 123-129. Abstractmateus_walen_antunes_-_2006_-_the_large_theropod_fauna_of_the_lourinha_formation__portugal__and_its_similarity_to_the_morrison_formation__with_a_description_of_a_new_species_of_allosaurus.pdf

Late Jurassic theropod dinosaurs have been known in Portugal since 1863 but only now are they being fully understood, with the recognition of genera such as Allosaurus, Aviatyrannis, Ceratosaurus, Lourinhanosaurus, and Torvosaurus from the Lourinhã and Alcobaça Formations (Kimmeridgian/Tithonian). Ceratosaurus dentisulcatus can now be reported from Portugal. It represents the only occurrence of this species outside the Morrison Formation.
New cranial elements confirm the presence of Torvosaurus tanneri, in Portugal. Torvosaurus was the largest Late Jurassic land carnivore. New postcranial and cranial elements allow the erection of a new species from Portugal, Allosaurus europaeus n.sp. The theropod assemblage of Portugal is similar to that of the Morrison Formation.

Belvedere, M., Castanera D., Meyer C. A., Marty D., Mateus O., Silva B. C., Santos V. F., & Cobos A. (2019).  Late Jurassic globetrotters compared: A closer look at large and giant theropod tracks of North Africa and Europe. Journal of African Earth Sciences. 158, 103547. Abstractbelvedere_et_al_2019_jurassic_globetrotters_compared.pdfWebsite

Late Jurassic theropod tracks are very common both in North Africa and Europe. Two recently described ichnotaxa Megalosauripus transjuranicus and Jurabrontes curtedulensis from the Kimmeridgian of Switzerland show the coexistence of two apex predators in the same palaeoenvironment. Similar tracks can be found in tracksites from the Iberian Peninsula and from Morocco. Here, we further explore the similarities among the Swiss ichnotaxa and the other tracks from Germany (Kimmeridgian), Spain (Tithonian-Berriasian), Portugal (Oxfordian-Tithonian) and Morocco (Kimmeridgian) through novel three-dimensional data comparisons. Specimens were grouped in two morphotypes: 1) large and gracile (30 < Foot Length<50 cm) and 2) giant and robust (FL > 50 cm). The analyses show a great morphological overlap among these two morphotypes and the Swiss ichnotaxa (Megalosauripus transjuranicus and Jurabrontes curtedulensis, respectively), even despite the differences in sedimentary environment and age. This suggests a widespread occurrence of similar ichnotaxa along the western margin of Tethys during the Late Jurassic. The new data support the hypothesis of a Gondwana-Laurasia faunal exchange during the Middle or early Late Jurassic, and the presence of migratory routes around the Tethys.

Mateus, O., Clemmensen L., Klein N., Wings O., Frobøse N., Milàn J., Adolfssen J., & Estrup E. (2014).  The Late Triassic of Jameson Land revisited: new vertebrate findings and the first phytosaur from Greenland. Journal of Vertebrate Paleontology. Program and Abstracts, 2014, 182.mateus_et_al2014-_jameson_land_revisited_-_svp_2014.pdf
Leal, A. A., Dionísio A., Braga M. A. S., & Mateus O. (2016).  The long term preservation of Late Jurassic sandstone dinosaur footprints in a museum environment. International Journal of Conservation Science. 7(3), 627-646. AbstractWebsite

This study focuses on the assessment of the degradation processes occurring in three sandstone infills of fossilized Late Jurassic ornithopod tridactyl footprints, found in 2001 in a coastline cliff in Porto das Barcas (Lourinhã, Portugal) and exhibited in a museum display since 2004. These dinosaur footprints present nowadays severe decay phenomena compromising their physical integrity and are leading gradually to their loss of value. The deterioration patterns were recorded, a map of their distribution was prepared and several samples were collected both in the dinosaur footprints and in the coastline cliff. Different analytical procedures were applied such as XRD, FTIR, FESEM and Ion Chromatography. A microclimatic survey was also performed and air temperature and relative humidity was measured during eight months both indoor and also outdoor. The decay patterns observed are a combination intrinsic and extrinsic factors the stone material, namely swelling of clay minerals in the rock matrix (smectite and chlorite-smectite mixed-layer), presence of salts (mainly chlorides), application of past conservation treatments (poly(vinyl) acetate and epoxy resins) and with the museum's indoor thermohygrometric conditions (mainly non-stable hygrometric conditions). This scientific knowledge is therefore essential to the sustainable preservation of this paleontological heritage.

Leal, A. A., Dion{\'ısio A., Braga M. A. S., & Mateus O. (2016).  The long term preservation of Late Jurassic sandstone dinosaur footprints in a museum environment. International Journal of Conservation Science. 7, 627-646. AbstractWebsite

This study focuses on the assessment of the degradation processes occurring in three sandstone infills of fossilized Late Jurassic ornithopod tridactyl footprints, found in 2001 in a coastline cliff in Porto das Barcas (Lourinhã, Portugal) and exhibited in a museum display since 2004. These dinosaur footprints present nowadays severe decay phenomena compromising their physical integrity and are leading gradually to their loss of value. The deterioration patterns were recorded, a map of their distribution was prepared and several samples were collected both in the dinosaur footprints and in the coastline cliff. Different analytical procedures were applied such as XRD, FTIR, FESEM and Ion Chromatography. A microclimatic survey was also performed and air temperature and relative humidity was measured during eight months both indoor and also outdoor. The decay patterns observed are a combination intrinsic and extrinsic factors the stone material, namely swelling of clay minerals in the rock matrix (smectite and chlorite-smectite mixed-layer), presence of salts (mainly chlorides), application of past conservation treatments (poly(vinyl) acetate and epoxy resins) and with the museum’s indoor thermohygrometric conditions (mainly non-stable hygrometric conditions). This scientific knowledge is therefore essential to the sustainable preservation of this paleontological heritage.

Leal, A. A., Dion\{\'ı\}sio A., Braga M. A. S., & Mateus O. (2016).  The long term preservation of Late Jurassic sandstone dinosaur footprints in a museum environment. International Journal of Conservation Science. 7, 627-646. Abstract
n/a
Leal, A. S., Dionísio A., Sequeira Braga M. A., & Mateus O. (2016).  The long term preservation of late jurassic sandstone dinossaur footprints in a museum environment. International Journal of Conservation Science. 7, 627-646., Number 3 Abstract
n/a
Mateus, O., and Dinis J., Cunha P. P., & and (2017).  The Lourinhã Formation: the Upper Jurassic to lower most Cretaceous of the Lusitanian Basin, Portugal – landscapes where dinosaurs walked. Ciências da Terra - Earth Sciences Journal. 19, 75–97., sep, Number 1: {NOVA}.{ID}.{FCT} AbstractWebsite
n/a
Mateus, O. (1998).  Lourinhanosaurus antunesi, a new Upper Jurassic allosauroid (Dinosauria : Theropoda) from Lourinha, Portugal. Memórias da Academia de Ciências de Lisboa. 37, 111-124. Abstract
n/a
Pereira, B. C., Benton M. J., Ruta M., & Mateus O. (2015).  Mesozoic echinoid diversity in Portugal: Investigating fossil record quality and environmental constraints on a regional scale. Palaeogeography, Palaeoclimatology, Palaeoecology. 424, 132 - 146. Abstractpereira_e_al_2015_mesozoic_echinoids_portugal.pdfWebsite

Abstract Several analyses of diversity through geological time use global, synoptic databases, and this practice often makes it difficult to distinguish true signals in changing diversity from regional-scale sampling and/or geological artefacts. Here we investigate how echinoid diversity changed through the Mesozoic of the Lusitanian basin in Portugal based on a comprehensive, revised database, and seek to distinguish biological signal from geological or environmental constraints. The observed diversity pattern is far from having a defined trend, showing many fluctuations that appear to be linked with gaps in the geological record. This study revealed that, independently of the method used, whether correlation tests or model fitting, the diversity signal is not completely explained by the studied sampling proxies. Among the different proxies, marine facies variation in combination with outcrop area best explains the palaeodiversity curve.

Pereira, B. C., Benton M. J., Ruta M., & Mateus O. (2015).  Mesozoic echinoid diversity in Portugal: Investigating fossil record quality and environmental constraints on a regional scale. Palaeogeography, Palaeoclimatology, Palaeoecology. 424, 132-146. Abstract
n/a
Hendrickx, C., Mateus O., & Buffetaut E. (2016).  Morphofunctional Analysis of the Quadrate of Spinosauridae (Dinosauria: Theropoda) and the Presence of Spinosaurus and a Second Spinosaurine Taxon in the Cenomanian of North Africa.. PLoS ONE. 11, e0144695., 01, Number 1: Public Library of Science Abstracthendrickx_et_al_2016_morphofunctional_analysis_of_the_quadrate_of_spinosauridae_dinosauria.pdfWebsite

Six quadrate bones, of which two almost certainly come from the Kem Kem beds (Cenomanian, Upper Cretaceous) of south-eastern Morocco, are determined to be from juvenile and adult individuals of Spinosaurinae based on phylogenetic, geometric morphometric, and phylogenetic morphometric analyses. Their morphology indicates two morphotypes evidencing the presence of two spinosaurine taxa ascribed to Spinosaurus aegyptiacus and? Sigilmassasaurus brevicollis in the Cenomanian of North Africa, casting doubt on the accuracy of some recent skeletal reconstructions which may be based on elements from several distinct species. Morphofunctional analysis of the mandibular articulation of the quadrate has shown that the jaw mechanics was peculiar in Spinosauridae. In mature spinosaurids, the posterior parts of the two mandibular rami displaced laterally when the jaw was depressed due to a lateromedially oriented intercondylar sulcus of the quadrate. Such lateral movement of the mandibular ramus was possible due to a movable mandibular symphysis in spinosaurids, allowing the pharynx to be widened. Similar jaw mechanics also occur in some pterosaurs and living pelecanids which are both adapted to capture and swallow large prey items. Spinosauridae, which were engaged, at least partially, in a piscivorous lifestyle, were able to consume large fish and may have occasionally fed on other prey such as pterosaurs and juvenile dinosaurs.

Hendrickx, C., Mateus O., & Buffetaut E. (2016).  Morphofunctional Analysis of the Quadrate of Spinosauridae (Dinosauria: Theropoda) and the Presence of Spinosaurus and a Second Spinosaurine Taxon in the Cenomanian of North Africa.. PLoS ONE. 11, e0144695., 01, Number 1: Public Library of Science AbstractWebsite

Six quadrate bones, of which two almost certainly come from the Kem Kem beds (Cenomanian, Upper Cretaceous) of south-eastern Morocco, are determined to be from juvenile and adult individuals of Spinosaurinae based on phylogenetic, geometric morphometric, and phylogenetic morphometric analyses. Their morphology indicates two morphotypes evidencing the presence of two spinosaurine taxa ascribed to Spinosaurus aegyptiacus and? Sigilmassasaurus brevicollis in the Cenomanian of North Africa, casting doubt on the accuracy of some recent skeletal reconstructions which may be based on elements from several distinct species. Morphofunctional analysis of the mandibular articulation of the quadrate has shown that the jaw mechanics was peculiar in Spinosauridae. In mature spinosaurids, the posterior parts of the two mandibular rami displaced laterally when the jaw was depressed due to a lateromedially oriented intercondylar sulcus of the quadrate. Such lateral movement of the mandibular ramus was possible due to a movable mandibular symphysis in spinosaurids, allowing the pharynx to be widened. Similar jaw mechanics also occur in some pterosaurs and living pelecanids which are both adapted to capture and swallow large prey items. Spinosauridae, which were engaged, at least partially, in a piscivorous lifestyle, were able to consume large fish and may have occasionally fed on other prey such as pterosaurs and juvenile dinosaurs.

Hendrickx, C., Bell P. R., Pittman M., Milner A. R. C., Cuesta E., O'Connor J., Loewen M., Currie P. J., Mateus O., Kaye T. G., & Delcourt R. (2022).  Morphology and distribution of scales, dermal ossifications, and other non-feather integumentary structures in non-avialan theropod dinosaurs. Biological Reviews. , Number n/a Abstracthendrickxetal.2021.morphologyanddistributionofscales.pdfWebsite

ABSTRACT Modern birds are typified by the presence of feathers, complex evolutionary innovations that were already widespread in the group of theropod dinosaurs (Maniraptoriformes) that include crown Aves. Squamous or scaly reptilian-like skin is, however, considered the plesiomorphic condition for theropods and dinosaurs more broadly. Here, we review the morphology and distribution of non-feathered integumentary structures in non-avialan theropods, covering squamous skin and naked skin as well as dermal ossifications. The integumentary record of non-averostran theropods is limited to tracks, which ubiquitously show a covering of tiny reticulate scales on the plantar surface of the pes. This is consistent also with younger averostran body fossils, which confirm an arthral arrangement of the digital pads. Among averostrans, squamous skin is confirmed in Ceratosauria (Carnotaurus), Allosauroidea (Allosaurus, Concavenator, Lourinhanosaurus), Compsognathidae (Juravenator), and Tyrannosauroidea (Santanaraptor, Albertosaurus, Daspletosaurus, Gorgosaurus, Tarbosaurus, Tyrannosaurus), whereas dermal ossifications consisting of sagittate and mosaic osteoderms are restricted to Ceratosaurus. Naked, non-scale bearing skin is found in the contentious tetanuran Sciurumimus, ornithomimosaurians (Ornithomimus) and possibly tyrannosauroids (Santanaraptor), and also on the patagia of scansoriopterygids (Ambopteryx, Yi). Scales are surprisingly conservative among non-avialan theropods compared to some dinosaurian groups (e.g. hadrosaurids); however, the limited preservation of tegument on most specimens hinders further interrogation. Scale patterns vary among and/or within body regions in Carnotaurus, Concavenator and Juravenator, and include polarised, snake-like ventral scales on the tail of the latter two genera. Unusual but more uniformly distributed patterning also occurs in Tyrannosaurus, whereas feature scales are present only in Albertosaurus and Carnotaurus. Few theropods currently show compelling evidence for the co-occurrence of scales and feathers (e.g. Juravenator, Sinornithosaurus), although reticulate scales were probably retained on the mani and pedes of many theropods with a heavy plumage. Feathers and filamentous structures appear to have replaced widespread scaly integuments in maniraptorans. Theropod skin, and that of dinosaurs more broadly, remains a virtually untapped area of study and the appropriation of commonly used techniques in other palaeontological fields to the study of skin holds great promise for future insights into the biology, taphonomy and relationships of these extinct animals.

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.

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.

Araújo, R., Polcyn M. J., Lindgren J., Jacobs L. L., Schulp A. S., Mateus O., Gonçalves O. A., & Morais M. - L. (2015).  New aristonectine elasmosaurid plesiosaur specimens from the Early Maastrichtian of Angola and comments on paedomorphism in plesiosaurs. Netherlands Journal of Geosciences. FirstView, 1–16., 2 Abstractaraujo_et_al_2015_paedomorphism-libre.pdfWebsite

ABSTRACT New elasmosaurid plesiosaur specimens are described from the Early Maastrichtian of Angola. Phylogenetic analyses reconstruct the Angolan taxon as an aristonectine elasmosaurid and the sister taxon of an unnamed form of similar age from New Zealand. Comparisons also indicate a close relationship with an unnamed form previously described from Patagonia. All of these specimens exhibit an ostensibly osteologically immature external morphology, but histological analysis of the Angolan material suggests an adult with paedomorphic traits. By extension, the similarity of the Angolan, New Zealand and Patagonian material indicates that these specimens represent a widespread paedomorphic yet unnamed taxon.

Araújo, R., Polcyn M. J., Lindgren J., Jacobs L. L., Schulp A. S., Mateus O., Gon?alves A. O., & Morais M. - L. (2014).  New aristonectine elasmosaurid plesiosaur specimens from the Early Maastrichtian of Angola and comments on paedomorphism in plesiosaurs. Geologie en Mijnbouw/Netherlands Journal of Geosciences. 94, 93-108., Number 1 Abstract
n/a
Moreno-Azanza, M., Pérez-Pueyo M., Puértolas-Pascual E., Núñez-Lahuerta C., Mateus O., Bauluz B., Bádenas B., & Canudo J. I. (2022).  A new crocodylomorph related ootaxon from the late Maastrichtian of the Southern Pyrenees (Huesca, Spain). Historical Biology. 1-10.: Taylor & Francis Abstracta_new_crocodylomorph_related_ootaxon_from_the_late_maastrichtian_of_the_southern_pyrenees_huesca_spain.pdfWebsite

ABSTRACTCrocodylomorph eggs and eggshells are known as old as the Late Jurassic and are frequent components of most multiootaxic eggshell assemblages. Classified within the oofamily Krokolithidae, thei histo- and ultrastructures are conservative throughout geological time, characterised by inverted-trapezoid-shaped shell units that grow from highly spaced basal knobs and present a diagnostic tabular ultrastructure. Here, we report 327 eggshell fragments from a new fossil site from the Maastrichtian of the Southern Pyrenees, Veracruz 1, and erect a new oogenus and oospecies, Pachykrokolithus excavatum oogen. et oosp. nov. characterised by crocodyloid morphotype and a prominent rugosocavate ornamentation. Eggshells from the slightly older locality of Blasi 2b, previously reported as aff. Krokolithidae, are also assigned to this new ootaxon. Different crocodylomorph taxa coexisted during the Late Cretaceous of the Tremp Basin, hindering the attribution of Pachykrokolithus excavatum oogen. et oosp. nov. to a single clade. Nevertheless, allodaposuchid eusuchians were dominant in this ecosystem, and are the most probable producers of Pachykrokolithus excavatum oogen. et oosp. nov. eggs.

Mateus, O., & Antunes M. T. (2003).  A New Dinosaur Tracksite in the Lower Cretaceous of Portugal. Ciências da Terra. 15, 253-262. Abstractmateus__antunes_2003-_early_k_dino_tracks_portugal.pdfWebsite

A new Lower Cretaceous (Aptian-Albian) dinosaur tracksite at the Olhos de Água beach is described. It is the first vertebrate fossil finding ever found in the concerned unit, and yielded 128 tracks in 17 trackways within an area of ca. 80 square metres.
Three tridactyl footprint morphotypes have been recognized: - Type 1 (“Iguanodontipus-like”) - trackways D, F, K, J and P; - Type 2 (large theropod), although larger in size, typically from a Grallator-like theropod footprint, i.e. A, B, G, H and O trackways; - Type 3 (medium size theropod); M is the only track of this type. There are other, poorly preserved, unidentified trackways. The theropod, swinging trackway B was produced by an animal that was limping. The theropod track M starts eastwards but drastically changes westwards, speeding up at the same time; this dinosaur decided to turn around and run in the opposite direction.
This site shows three main trackway directions: to the South, to the East, and westwards. Except for the trackway O, large theropods A, B, G and H walked southwards. Perpendicularly to these, ornithopods, small theropods and unidentified trackmakers walked towards East (5) and West (7). The segregation of trackmakers and directions, with large theropod trackways southwards and other dinosaurs’ west or eastwards, may mean that large theropods patrolled a walkway area to an important resource, most probably water, often frequented by ornithopods and smaller theropods. There is no evidence of social behavior or gregarism: footprints’ overposition shows that the large, southwards walking theropods passed on different occasions. Three trackway sequences can be established by chronologic order.