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2024
Rotatori, F. M., Ferrari L., Sequero C., Camilo B., Mateus O., & Moreno-Azanza M. (2024).  An unexpected early-diverging iguanodontian dinosaur (Ornithischia, Ornithopoda) from the Upper Jurassic of Portugal. Journal of Vertebrate Paleontology. e2310066.: Taylor & Francis AbstractWebsite

Iguanodontia is a diverse clade of herbivorous ornithischian dinosaurs that were speciose and abundant during the Jurassic and Cretaceous. Although the monophyly of Iguanodontia is well supported, their internal relationships have sparked heated debate due to several phylogenetic paradigm shifts. Late Jurassic basally branching iguanodontians in particular are not well understood in terms of their systematic affinities and evolutionary relevance. Their fossil record in Europe is meager compared with North America, with only a few species currently recognized. Two taxa are currently known from the Upper Jurassic of England, the basally branching styracosternan Cumnoria prestwichii and the putative dryosaurid Callovosaurus leedsi. In the Upper Jurassic of Portugal, the styracosternan Draconyx loureiroi and the dryosaurid Eousdryosaurus nanohallucis are presently the only described basally branching iguanodontians. Here we report a new species of early diverging iguanodontian from the Upper Jurassic Lourinhã Formation of western-central Portugal. The new species is clearly distinguished from all other coeval taxa by an exclusive combination of characters that include a tibia with a cnemial crest that is directed craniolaterally and a fibular condyle that is angled at 90° with respect to the proximal epiphysis, a fibula with symmetrical proximal margins, and a reduced metatarsal I. The phylogenetic relationships of the Lourinhã iguanodontian were explored using maximum parsimony and Bayesian inference. The two analyses recover the Lourinhã iguanodontian as an indeterminate dryomorphan, with more precise affinities precluded due to the current available material. Body size is estimated between 3 and 4 meters for the holotype specimen, adding to the diversity of small ornithopods already recognized in the paleoichnological record of the Lourinhã Formation. http://zoobank.org/urn:lsid:zoobank.org:pub:5F4D52D0-0F0B-4809-8561-BE58C7C97D45

Jacobs, L. L., Schröder S., de Sousa N., Dixon R., Fiordalisi E., Marechal A., Mateus O., Nsungani P. C., Polcyn M. J., do Pereira G. C. R., Rochelle-Bates N., Schulp A. S., Scotese C. R., Sharp I., Silvano C. G., Swart R., & Vineyard D. P. (2024).  The Atlantic jigsaw puzzle and the geoheritage of Angola. Geological Society, London, Special Publications. 543, SP543-2022-301., Number 1 AbstractWebsite

The jigsaw-puzzle fit of South America and Africa is an icon of plate tectonics and continental drift. Fieldwork in Angola since 2002 allows the correlation of onshore outcrops and offshore geophysical and well-core data in the context of rift, sag, salt, and post-salt drift phases of the opening of the central South Atlantic. These outcrops, ranging in age from >130 Ma to <71 Ma, record Early Cretaceous outpouring of the Etendeka-Paraná Large Igneous Province (Bero Volcanic Complex) and rifting, followed by continental carbonate and siliciclastic deposition (Tumbalunda Formation) during the sagging of the nascent central South Atlantic basin. By the Aptian, evaporation of sea water resulted in thick salt deposits (Bambata Formation), terminated by sea floor spreading. The Equatorial Atlantic Gateway began opening by the early Late Cretaceous (100 Ma) and allowed flow of currents between the North and South Atlantic, creating environmental conditions that heralded the introduction of marine reptiles. These dramatic outcrops are a unique element of geoheritage because they arguably comprise the most complete terrestrially exposed geological record of the puzzle-like icon of continental drift.

2023
Werneburg, I., Pommery Y., Ruciński M., Kästle B., Cohen G. J., Natchev N., Mateus O., & Ferreira G. D. (2023).  Functional morphology of the skull of Henodus chelyops (Placodontia). International Congress of Vertebrate Morphology Cairns - QLD - Australia 28 July - 1 August 2023. The Anatomical Record. 232-233. Abstractwerneburg_et_al_2023_henodus_icvm_2023_abstracts_updated_8_14-1693344432.pdf

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Fernandes, A. E., Beccari V., Kellner A. W. A., & Mateus O. (2023).  A new gnathosaurine (Pterosauria, Archaeopterodactyloidea) from the Late Jurassic of Portugal. PeerJ. 11, e16048. Abstractfernandes_et_al_2023_lusognathus_peerj-16048.pdfWebsite

An incomplete, yet remarkably-sized dentated rostrum and associated partial cervical vertebrae of a pterosaur (ML 2554) were recently discovered from the Late Jurassic (Late Kimmeridgian-Early Tithonian) Lourinhã Formation of Praia do Caniçal, of central west Portugal. This specimen exhibits features such as a spatulated anterior expansion of the rostrum, robust comb-like dentition, and pronounced rims of the tooth alveoli, indicating gnathosaurine affinities. Based on its further unique tooth and dentary morphology, a new genus and species, \textit{Lusognathus almadrava} gen. et spec. nov., is proposed, making this the first named pterosaur species found within Portugal. The presence of this taxon adds yet another element to the fluvio-deltaic lagoonal environment that has been suggested as representative of the Lourinhã Formation in the Late Jurassic, further contributing to the diversity and distribution of gnathosaurines worldwide.

2022
Fernandes, A. F., Beccari V., Kellner A. W. A., & Mateus O. (2022).  A new Gnathosaurine (Archaeopterodactyloidea, Pterosauria) from the Late Jurassic of Portugal. XIX Annual Conference of the European Association of Vertebrate Palaeontologists. 56-57. Abstractfernandes_et_al_2022_pterosaur_eavp_2022_abstract_volume.pdf

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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

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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.

2021
Fernandes, A. E., Mateus O., Bauluz B., Coimbra R., Ezquerro L., Núñez-Lahuerta C., Suteu C., & Moreno-Azanza M. (2021).  The Paimogo Dinosaur Egg Clutch Revisited: Using One of Portugal’s Most Notable Fossils to Exhibit the Scientific Method. Geoheritage. 13(3), 66., 2021 Abstractfernandes_et_al-2021-geoheritage.pdfWebsite

Found in the Upper Jurassic outcrops of Lourinhã, Portugal, and first published in 1997, the Paimogo dinosaur egg clutch is one of Portugal’s most remarkable fossils, with over one hundred eggs preserved in association with embryonic bones, of the allosauroid theropod Lourinhanosaurus. However, many questions about it have remained unanswered, even until the present day. After its discovery, this extraordinary fossil became the keystone of a small local museum, greatly kick-starting regional tourism, while also holding the fossils in trust for future generations to study. More than 20 years later, continually sustained paleontological interest from the public has even given rise to both a highly successful dinosaur theme park in the region and an aspiring UNESCO Geopark. Recently, a multidisciplinary team of preparators, paleontologists, sedimentologists, mineralogists, and geochemists revisited an unopened jacket from the original excavation using an array of techniques to address various questions. Studies are ongoing, but the corpus of information obtained and the methodologies utilized to gather data have offered an opportunity to design an exhibit around the history of the Paimogo clutch, highlighting the scientific methods involved, and asserting the importance of preserving geological heritage for the future, when new tools will doubtlessly become available to provide yet another new look at old fossils. Here, we describe our analytical procedures and present an innovative exhibit designed to introduce to the public the latest advances on the research behind an iconic piece of Portuguese geoheritage, increasing its value both as a research item and as an educational resource.

Puértolas-Pascual, E., Marx M., Mateus O., Saleiro A., Fernandes A. E., Marinheiro J., Tomás C., & Mateus S. (2021).  A new plesiosaur from the Lower Jurassic of Portugal and the early radiation of Plesiosauroidea. Acta Palaeontologica Polonica. 66(2), 369-388. Abstracta_new_plesiosaur_from_the_lower_jurassic_of_portugal_and_the_early_radiation_of_plesiosauroidea.pdfWebsite

A new plesiosaur partial skeleton, comprising most of the trunk and including axial, limb, and girdle bones, was collected in the lower Sinemurian (Coimbra Formation) of Praia da Concha, near São Pedro de Moel in central west Portugal. The specimen represents a new genus and species, Plesiopharos moelensis gen. et sp. nov. Phylogenetic analysis places this taxon at the base of Plesiosauroidea. Its position is based on this exclusive combination of characters: presence of a straight preaxial margin of the radius; transverse processes of mid-dorsal vertebrae horizontally oriented; ilium with sub-circular cross section of the shaft and subequal anteroposterior expansion of the dorsal blade; straight proximal end of the humerus; and ventral surface of the humerus with an anteroposteriorly long shallow groove between the epipodial facets. In addition, the new taxon has the following autapomorphies: iliac blade with less expanded, rounded and convex anterior flank; highly developed ischial facet of the ilium; apex of the neural spine of the first pectoral vertebra inclined posterodorsally with a small rounded tip. This taxon represents the most complete and the oldest plesiosaur species in the Iberian Peninsula. It is also the most complete, best preserved, and oldest marine vertebrate in the region and testifies to the incursion of marine reptiles in the newly formed proto-Atlantic sea, prior to the Atlantic Ocean floor spreading in the Early Cretaceous.

2019
Mateus, O., Callapez P. M., Polcyn M. J., Schulp A. S., Gonçalves A. O., & Jacobs L. L. (2019).  The Fossil Record of Biodiversity in Angola Through Time: A Paleontological Perspective. (Huntley, Brian J., Russo, Vladimir, Lages, Fernanda, Ferrand, Nuno, Ed.).Biodiversity of Angola: Science & Conservation: A Modern Synthesis. 53–76.: Springer International Publishing Abstractmateus2019_chapter_thefossilrecordofbiodiversityi.pdf

This chapter provides an overview of the alpha paleobiodiversity of Angola based on the available fossil record that is limited to the sedimentary rocks, ranging in age from Precambrian to the present. The geological period with the highest paleobiodiversity in the Angolan fossil record is the Cretaceous, with more than 80{%} of the total known fossil taxa, especially marine molluscs, including ammonites as a majority among them. The vertebrates represent about 15{%} of the known fauna and about one tenth of them are species firstly described based on specimens from Angola.

Mateus, O., Callapez P. M., Polcyn M. J., Schulp A. S., Gonçalves A. O., & Jacobs L. L. (2019).  O registo fóssil da biodiversidade em Angola ao longo do tempo: uma perspectiva paleontológica. (Huntley B.J., Russo V., Lages F., Ferrand N., Ed.).Biodiversidade de Angola: Ciência e Conservação - Uma Síntese Moderna. 89-116., Porto: Arte & Ciência Abstractmateus_et_al_2019_paleobiodiversidade_angola.pdf

Este capítulo apresenta uma visão geral da paleobiodiversidade alfa de Angola com base no registo fóssil disponível, o qual se limita às rochas sedimentares, a sua idade variando entre o Pré‑Câmbrico e o pre‑
sente. O período geológico com a maior paleobiodiversidade no registo fóssil angolano é o Cretácico, com mais de 80% do total dos táxones fósseis conhecidos, especialmente moluscos marinhos, sendo estes na sua maioria
amonites. Os vertebrados representam cerca de 15% da fauna conhecida e cerca de um décimo destes são espécies descritas pela primeira vez com base em espécimes de Angola.

Mateus, O., Callapez P. M., Polcyn M. J., Schulp A. S., Gonçalves A. O., & Jacobs L. L. (2019).  The Fossil Record of Biodiversity in Angola Through Time: A Paleontological Perspective. (Huntley, Brian J., Russo, Vladimir, Lages, Fernanda, Ferrand, Nuno, Ed.).Biodiversity of Angola: Science {&} Conservation: A Modern Synthesis. 53–76., Cham: Springer International Publishing Abstract

This chapter provides an overview of the alpha paleobiodiversity of Angola based on the available fossil record that is limited to the sedimentary rocks, ranging in age from Precambrian to the present. The geological period with the highest paleobiodiversity in the Angolan fossil record is the Cretaceous, with more than 80{%} of the total known fossil taxa, especially marine molluscs, including ammonites as a majority among them. The vertebrates represent about 15{%} of the known fauna and about one tenth of them are species firstly described based on specimens from Angola.

2017
Costa, F., Silva T., Fernandes J., Calvo R., & Mateus O. (2017).  Retracing the history of a stegosaurian dinosaur discovery in Portugal and the importance of record-keeping in Palaentology. Abstract book of the XV Encuentro de Jóvenes Investigadores en Paleontología/XV Encontro de Jovens Investigadores em Paleontologia, Lisboa, 428 pp.. 119-124. Abstractcosta_et_al_2017_retracing_the_history_-_2017.pdf

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2016
Silva, T., Costa F., Fernandes J., Calvo R., & Mateus O. (2016).  The use of a portable X-ray fluorescence analyzer in the reconstitution of dinosaur fossils. , 7: European Conference on X-Ray Spectrometry (EXRS) Abstract

Portable X-ray fluorescence spectrometers (p-XRF) have been used in many fields of application/studies like art, archaeology, heavy metals in soil, rocks and ores characterization, and have been a powerful tool for a rapid non-destructive in-situ analysis, without any sample preparation required. This approach was applied in the present case, to distinguish the origin of the fossil bones of two dinosaur specimens from different localities that were accidentally put together in the museum a few years ago. Fossil bones with sedimentary matrix associated were stored together until today in the collection of Geological Museum (Lisbon) and regarded as one single specimen. One set of bones is part of the holotype MG 5787 of the ankylosaur Dracopelta zbyszweskii, which was discovered at Praia do Sul, and described in 1980, while the other, is an undescribed half skeleton of dacentrurine stegosaur, unearthed in the 1960’s at Atouguia da Baleia, near Peniche (both in the coast of central Portugal, distanced about 100 km from each other). Since both specimens are highly valuable for paleontology, a study was developed with the aim of separating and reconstituting the two specimens. The handheld p-XRF (Genius 9000+7000 from Skyray Instrument) was directly used in the sedimentary matrix when it was separated from the bone, and the measure of the chemical content was performed in the intermediate layer between the surface and the bone, to avoid contaminations. Although the light elements could not be attained, because the analyzer is not equipped with the option of gas charging system, the spectra obtained showed differences mainly in the ratio K/Ca, allowing distinguishing the provenance of the bones (Atouguia or Praia do Sul). These results were compared with chemical analysis obtained with XRF laboratorial equipment and complemented by the mineralogical study through X-ray diffraction (XRD) of the sediments where the bones fossilized. The difference observed in the mineralogical constitution of the sedimentary matrix from the two localities (mainly quartz, calcite, feldspars and micas with variable content) explains the variation in the values found for the ratio K/Ca (<0.5 for Atouguia and >>1 for Praia do Sul). The data obtained will be presented and discussed focusing on the importance of using a portable X-ray fluorescence analyzer applied to the reconstitution of dinosaur fossils that proved to be very useful in the present case.

Ceríaco, L. M. P., Gutiérrez E. E., Dubois A., Abdala C. S., Alqarni A. S., Adler K., et al. (2016).  Photography-based taxonomy is inadequate, unnecessary, and potentially harmful for biological sciences. Zootaxa. 4196(3), 435 - 445., 2016 AbstractWebsite
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Klein, H., Milàn J., Clemmensen L. B., Frobøse N., Mateus O., Klein N., Adolfssen J. S., Estrup E. J., & Wings O. (2016).  Archosaur footprints (cf. Brachychirotherium) with unusual morphology from the Upper Triassic Fleming Fjord Formation (Norian–Rhaetian) of East Greenland. Geological Society, London, Special Publications. 434(1), 71-85. Abstractklein_et_al_2015_archosaur_footprints_cf._brachychirotherium_with_unusual.pdfWebsite

The Ørsted Dal Member of the Upper Triassic Fleming Fjord Formation in East Greenland is well known for its rich vertebrate fauna, represented by numerous specimens of both body and ichnofossils. In particular, the footprints of theropod dinosaurs have been described. Recently, an international expedition discovered several slabs with 100 small chirotheriid pes and manus imprints (pes length 4–4.5 cm) in siliciclastic deposits of this unit. They show strong similarities with Brachychirotherium, a characteristic Upper Triassic ichnogenus with a global distribution. A peculiar feature in the Fleming Fjord specimens is the lack of a fifth digit, even in more deeply impressed imprints. Therefore, the specimens are assigned here tentatively to cf. Brachychirotherium. Possibly, this characteristic is related to the extremely small size and early ontogenetic stage of the trackmaker. The record from Greenland is the first evidence of this morphotype from the Fleming Fjord Formation. Candidate trackmakers are crocodylian stem group archosaurs; however, a distinct correlation with known osteological taxa from this unit is not currently possible. While the occurrence of sauropodomorph plateosaurs in the bone record links the Greenland assemblage more closer to that from the Germanic Basin of central Europe, here the described footprints suggest a Pangaea-wide exchange.Supplementary material: Three-dimensional model of cf. Brachychirotherium pes–manus set (from MGUH 31233b) from the Upper Triassic Fleming Fjord Formation (Norian–Rhaetian) of East Greenland as pdf, ply and jpg files (3D model created by Oliver Wings; photographs taken by Jesper Milàn) is available at https://doi.org/10.6084/m9.figshare.c.2133546

Ceríaco, L. M. P., Gutiérrez E. E., Dubois A., Abdala C. S., Alqarni A. S., Adler K., et al. (2016).  Photography-based taxonomy is inadequate, unnecessary, and potentially harmful for biological sciences. Zootaxa. 4196, 435-445., Number 3 Abstract
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Silva, T., Costa F., Fernandes J., Calvo R., & Mateus O. (2016).  The use of a portable X-ray fluorescence analyzer in the reconstitution of dinosaur fossils. European Conference on X-Ray Spectrometry. , June 19 – 24, 2016, Gothenburg, Sweden Abstract
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Silva, T., Costa F., Fernandes J., Calvo R. \é\}rio, & Mateus O. \á\}vio (2016).  The use of a portable X-ray fluorescence analyzer in the reconstitution of dinosaur fossils. European Conference on X-Ray Spectrometry. , June 19 \–\} 24, 2016, Gothenburg, Sweden Abstract
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2015
Foth, C., Evers S. W., Pabst B., Mateus O., Flisch A., Patthey M., & Rauhut O. W. M. (2015).  New insights into the lifestyle of \\textitAllosaurus (Dinosauria: Theropoda) based on another specimen with multiple pathologies. PeerJ. 3, e940., 5 AbstractWebsite

Adult large-bodied theropods are often found with numerous pathologies. A large, almost complete, probably adult \\textitAllosaurus specimen from the Howe Stephens Quarry, Morrison Formation (Late Kimmeridgian–Early Tithonian), Wyoming, exhibits multiple pathologies. Pathologic bones include the left dentary, two cervical vertebrae, one cervical and several dorsal ribs, the left scapula, the left humerus, the right ischium, and two left pedal phalanges. These pathologies can be classified as follows: the fifth cervical vertebra, the scapula, several ribs and the ischium are probably traumatic, and a callus on the shaft of the left pedal phalanx II-2 is probably traumatic-infectious. Traumatically fractured elements exposed to frequent movement (e.g., the scapula and the ribs) show a tendency to develop pseudarthroses instead of a callus. The pathologies in the lower jaw and a reduced extensor tubercle of the left pedal phalanx II-2 are most likely traumatic or developmental in origin. The pathologies on the fourth cervical are most likely developmental in origin or idiopathic, that on the left humerus could be traumatic, developmental, infectious or idiopathic, whereas the left pedal phalanx IV-1 is classified as idiopathic. With exception of the ischium, all as traumatic/traumatic-infectious classified pathologic elements show unambiguous evidences of healing, indicating that the respective pathologies did not cause the death of this individual. Alignment of the scapula and rib pathologies from the left side suggests that all may have been caused by a single traumatic event. The ischial fracture may have been fatal. The occurrence of multiple lesions interpreted as traumatic pathologies again underlines that large-bodied theropods experienced frequent injuries during life, indicating an active predatory lifestyle, and their survival perhaps supports a gregarious behavior for \\textitAllosaurus. Alternatively, the frequent survival of traumatic events could be also related to the presence of non-endothermic metabolic rates that allow survival based on sporadic food consumption or scavenging behavior. Signs of pathologies consistent with infections are scarce and locally restricted, indicating a successful prevention of the spread of pathogens, as it is the case in extant reptiles (including birds).

Foth, C., Evers S., Pabst B., Mateus O., Flisch A., Patthey M., & Rauhut O. W. M. (2015).  New insights into the lifestyle of Allosaurus (Dinosauria: Theropoda) based on another specimen with multiple pathologies. PeerJ PrePrints. 3, e824v1., 2015 Abstractfoth_et_al_2015_peerj-preprints-824.pdfWebsite

Adult large-bodied theropods are often found with numerous pathologies. A large, almost complete, probably adult Allosaurus specimen from the Howe Stephens Quarry, Morrison Formation (Late Kimmeridgian–Early Tithonian), Wyoming, shows multiple pathologies. Pathologic bones include the left dentary, two cervical vertebrae, one cervical and several dorsal ribs, the left scapula, the left humerus, right ischium, and two left pedal phalanges. These pathologies can be classified as follows: the fifth cervical vertebra, the scapula, several ribs and the ischium are traumatic, and a callus on the shaft of the left pedal phalanx II-2 is traumatic-infectious. Traumatically fractured elements exposed to frequent movement (e.g. the scapula and the ribs) show a tendency to develop pseudarthroses instead of callus healing. The pathologies in the lower jaw and a reduced flexor tubercle of the left pedal phalanx II-2 are most likely traumatic or developmental in origin. The pathologies on the fourth cervical are most likely developmental in origin or idiopathic, that on the left humerus is infectious or idiopathic, whereas left pedal phalanx IV-1 is classified as idiopathic. With exception of the ischium, all traumatic / traumatic-infectious pathologic elements show unambiguous evidences of healing, indicating that the respective pathologies did not cause the death of this individual. Alignment of the scapula and rib pathologies from the left side suggests that all may have been caused by a single traumatic event. The ischial fracture may have been fatal. The occurrence of multiple traumatic pathologies again underlines that large-bodied theropods experienced frequent injuries during life, indicating an active predatory lifestyle, and their survival perhaps supports a gregarious behavior for Allosaurus. Signs of infections are scarce and locally restricted, indicating a successful prevention of the spread of pathogens, as it is the case in extant reptiles (including birds).

Strganac, C., Jacobs L. L., Polcyn M. J., Ferguson K. M., Mateus O., Gonçalves O. A., Morais M. - L., & da Silva Tavares T. (2015).  Stable oxygen isotope chemostratigraphy and paleotemperature regime of mosasaurs at Bentiaba, Angola. Netherlands Journal of Geosciences. FirstView, 1–7., 2 Abstractstrganac_etal2015_stable_oxigen_isotopes.pdfWebsite

ABSTRACT Stable oxygen isotope values of inoceramid marine bivalve shells recovered from Bentiaba, Angola, are utilised as a proxy for paleotemperatures during the Late Cretaceous development of the African margin of the South Atlantic Ocean. The δ18O values derived from inoceramids show a long-term increase from –3.2‰ in the Late Turonian to values between –0.8 and –1.8‰ in the Late Campanian. Assuming a constant oceanic δ18O value, an ∼2‰ increase may reflect cooling of the shallow marine environment at Bentiaba by approximately 10°. Bentiaba values are offset by about +1‰ from published records for bathyal Inoceramus at Walvis Ridge. This offset in δ18O values suggests a temperature difference of ∼5° between coastal and deeper water offshore Angola. Cooler temperatures implied by the δ18O curve at Bentiaba coincide with the stratigraphic distribution of diverse marine amniotes, including mosasaurs, at Bentiaba.

Young, M. T., Hua S., Steel L., Foffa D., Brusatte S. L., Thüring S., Mateus O., Ruiz-Omeñaca J. I., Havlik P., Lepage Y., & de Andrade M. B. (2015).  Addendum to ‘Revision of the Late Jurassic teleosaurid genus Machimosaurus (Crocodylomorpha, Thalattosuchia)’. Royal Society Open Science. 2, , Number 2: The Royal Society Abstractyoung_et_al_2015_addendum_to_revision_of_the_late_jurassic_teleosaurid_genus_machimosaurus_crocodylomorpha_thalattosuchia.pdfWebsite

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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.

Clemmensen, L. B., Milàn J., Adolfssen J. S., Estrup E. J., Frobøse N., Klein N., Mateus O., & Wings O. (2015).  The vertebrate-bearing Late Triassic Fleming Fjord Formation of central East Greenland revisited: stratigraphy, palaeoclimate and new palaeontological data. Geological Society, London, Special Publications. 434(1), 31-47. Abstractclemmensenetal2015greenland.pdfWebsite

In Late Triassic (Norian–Rhaetian) times, the Jameson Land Basin lay at 40° N on the northern part of the supercontinent Pangaea. This position placed the basin in a transition zone between the relatively dry interior of the supercontinent and its more humid periphery. Sedimentation in the Jameson Land Basin took place in a lake–mudflat system and was controlled by orbitally forced variations in precipitation. Vertebrate fossils have consistently been found in these lake deposits (Fleming Fjord Formation), and include fishes, dinosaurs, amphibians, turtles, aetosaurs and pterosaurs. Furthermore, the fauna includes mammaliaform teeth and skeletal material. New vertebrate fossils were found during a joint vertebrate palaeontological and sedimentological expedition to Jameson Land in 2012. These new finds include phytosaurs, a second stem testudinatan specimen and new material of sauropodomorph dinosaurs, including osteologically immature individuals. Phytosaurs are a group of predators common in the Late Triassic, but previously unreported from Greenland. The finding includes well-preserved partial skeletons that show the occurrence of four individuals of three size classes. The new finds support a late Norian–early Rhaetian age for the Fleming Fjord Formation, and add new information on the palaeogeographical and palaeolatitudinal distribution of Late Triassic faunal provinces.

Young, M. T., Hua S., Steel L., Foffa D., Brusatte S. L., Thüring S., Mateus O., Ruiz-Omeñaca J. I., Havlik P., Lepage Y., & De Andrade M. B. (2015).  Addendum to ?Revision of the Late Jurassic teleosaurid genus Machimosaurus (Crocodylomorpha, Thalattosuchia)?. Royal Society Open Science. 2, , Number 2 Abstract
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Klein, H., Milàn J., Clemmensen L. B., Frobøse N., Mateus O., Klein N., Adolfssen J. S., Estrup E. J., & Wings O. (2015).  Archosaur footprints (cf. Brachychirotherium) with unusual morphology from the Upper Triassic Fleming Fjord Formation (Norian–Rhaetian) of East Greenland. Geological Society, London, Special Publications. 434, AbstractWebsite

The Ørsted Dal Member of the Upper Triassic Fleming Fjord Formation in East Greenland is well known for its rich vertebrate fauna, represented by numerous specimens of both body and ichnofossils. In particular, the footprints of theropod dinosaurs have been described. Recently, an international expedition discovered several slabs with 100 small chirotheriid pes and manus imprints (pes length 4–4.5 cm) in siliciclastic deposits of this unit. They show strong similarities with Brachychirotherium, a characteristic Upper Triassic ichnogenus with a global distribution. A peculiar feature in the Fleming Fjord specimens is the lack of a fifth digit, even in more deeply impressed imprints. Therefore, the specimens are assigned here tentatively to cf. Brachychirotherium. Possibly, this characteristic is related to the extremely small size and early ontogenetic stage of the trackmaker. The record from Greenland is the first evidence of this morphotype from the Fleming Fjord Formation. Candidate trackmakers are crocodylian stem group archosaurs; however, a distinct correlation with known osteological taxa from this unit is not currently possible. While the occurrence of sauropodomorph plateosaurs in the bone record links the Greenland assemblage more closer to that from the Germanic Basin of central Europe, here the described footprints suggest a Pangaea-wide exchange.Supplementary material: Three-dimensional model of cf. Brachychirotherium pes–manus set (from MGUH 31233b) from the Upper Triassic Fleming Fjord Formation (Norian–Rhaetian) of East Greenland as pdf, ply and jpg files (3D model created by Oliver Wings; photographs taken by Jesper Milàn) is available at https://doi.org/10.6084/m9.figshare.c.2133546

Clemmensen, L. B., Milàn J., Adolfssen J. S., Estrup E. J., Frobøse N., Klein N., Mateus O., & Wings O. (2015).  The vertebrate-bearing Late Triassic Fleming Fjord Formation of central East Greenland revisited: stratigraphy, palaeoclimate and new palaeontological data. Geological Society, London, Special Publications. 434, AbstractWebsite

In Late Triassic (Norian–Rhaetian) times, the Jameson Land Basin lay at 40° N on the northern part of the supercontinent Pangaea. This position placed the basin in a transition zone between the relatively dry interior of the supercontinent and its more humid periphery. Sedimentation in the Jameson Land Basin took place in a lake–mudflat system and was controlled by orbitally forced variations in precipitation. Vertebrate fossils have consistently been found in these lake deposits (Fleming Fjord Formation), and include fishes, dinosaurs, amphibians, turtles, aetosaurs and pterosaurs. Furthermore, the fauna includes mammaliaform teeth and skeletal material. New vertebrate fossils were found during a joint vertebrate palaeontological and sedimentological expedition to Jameson Land in 2012. These new finds include phytosaurs, a second stem testudinatan specimen and new material of sauropodomorph dinosaurs, including osteologically immature individuals. Phytosaurs are a group of predators common in the Late Triassic, but previously unreported from Greenland. The finding includes well-preserved partial skeletons that show the occurrence of four individuals of three size classes. The new finds support a late Norian–early Rhaetian age for the Fleming Fjord Formation, and add new information on the palaeogeographical and palaeolatitudinal distribution of Late Triassic faunal provinces.

2014
Strganac, C., Salminen J., Jacobs L. L., Ferguson K. M., Polcyn M. J., Mateus O., Schulp A. S., Morais M. L., Tavares T. S., & Gonçalves A. O. (2014).  Carbon isotope stratigraphy and 40Ar/39Ar age of the Cretaceous South Atlantic coast, Namibe Basin, Angola. Journal of African Earth Sciences. onine, 1-11. Abstractstrganac_et_al_2014_carbon_isotope_stratigraphy_magnetostratigraphy_and_40ar_39ar_age_of.pdfWebsite

We present the δ13C and paleomagnetic stratigraphy for marine strata at the coast of southern Angola, anchored by an intercalated basalt with a whole rock 40Ar/39Ar radiometric age of 84.6 ± 1.5 Ma, being consistent with both invertebrate and vertebrate biostratigraphy. This is the first African stable carbon isotope record correlated to significant events in the global carbon cycle spanning the Late Cenomanian to Early Maastrichtian. A positive ∼ 3‰ excursion seen in bivalve shells below the basalt indicates the Cenomanian-Turonian Boundary Event at 93.9 Ma, during Oceanic Anoxic Event 2. Additional excursions above the basalt are correlated to patterns globally, including a negative ∼ 3‰ excursion near the top of the section interpreted as part of the Campanian-Maastrichtian Boundary Events. The age of the basalt ties the studied Bentiaba section to a pulse of Late Cretaceous magmatic activity around the South Atlantic and significant tectonic activity, including rotation, of the African continent.

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
Young, M. T., Hua S., Steel L., Foffa D., Brusatte S. L., Thüring S., Mateus O., Ignacio-Ruiz Omeñaca J., Lepage Y., Havilk P., & Andrade M. B. (2014).  Revision of the Late Jurassic teleosaurid genus Machimosaurus (Crocodylomorpha, Thalattosuchia). Royal Society Open Science. 1(140222), 1-42.young_et_al_2014_machimosaurus_crocodylomorph_revision.pdf
Strganac, C., Salminen J., Jacobs L. L., Polcyn M. J., Ferguson K. M., Mateus O., Schulp A. S., Morais M. L., Tavares T. S., & Gon?alves A. O. (2014).  Carbon isotope stratigraphy, magnetostratigraphy, and 40Ar/39Ar age of the cretaceous South Atlantic coast, Namibe Basin, Angola. Journal of African Earth Sciences. 99, 452-462., Number PA2 Abstract
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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
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Young, M. T., Hua S., Steel L., Foffa D., Brusatte S. L., Thüring S., Mateus O., Ruiz-Omeñaca J. I., Havlik P., Lepage Y., & De Andrade M. B. (2014).  Revision of the Late Jurassic teleosaurid genus Machimosaurus (Crocodylomorpha, Thalattosuchia). Royal Society Open Science. 1, , Number 2 Abstract
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Strganac, C., Jacobs L. L., Polcyn M. J., Ferguson K. M., Mateus O., Gon?alves A. O., Morais M. - L., & da Silva Tavares T. (2014).  Stable oxygen isotope chemostratigraphy and paleotemperature regime of mosasaurs at Bentiaba, Angola. Geologie en Mijnbouw/Netherlands Journal of Geosciences. 94, 137-143., Number 1 Abstract
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2013
Strganac, C., Jacobs L. L., Ferguson K. M., Polcyn M. J., Mateus O., Schulp A. S., & Morais M. L. (2013).  Late Cretaceous marine reptiles and cooling at the South Atlantic coast inferred through stable oxygen isotopes of Inoceramus from the Namibe Basin, Angola. Geological Society of America Abstracts with Programs. Vol. 45, No. 7, p.0.
2012
Strganac, C., Ferguson, K.M, Jacobs J. L., Polcyn M. J., & Mateus O. (2012).  Age and paleoecology of mosasaurs and plesiosaurs from the Late Cretaceous South Atlantic margin at Bentiaba, Angola. Journal of Vertebrate Paleontology, Program and Abstracts, 2012. 180.strganac_et_al_mateus_2012_age_bentiaba_angola_2012_svp_abstract.pdf
Milàn, J., Clemmensen L. B., Adolfssen J. S., Estrup E. J., Frobøse N., Klein N., Mateus O., & Wings O. (2012).  A preliminary report on coprolites from the Late Triassic part of the Kap Stewart Formation, Jameson Land, East Greenland. New Mexico Museum of Natural History and Science, Bulletin. 57, 203-205. Abstractmilan_et_al_2012_greenland_coprolites_triassic.pdf

The basal part of the Triassic-Jurassic (Rhaetian-Sinemurian) Kap Stewart Formation, exposed at Jameson Land, East Greenland, yields an extensive coprolite collection from black, parallel-laminated mudstone (“paper shale”), representing an open lacustrine system. Preliminary investigations show three different types of coprolites: elongated cylindrical masses, composed of irregularly wrapped layers; elongated cylindrical masses with constriction marks; and spirally-coiled specimens.

2010
Jacobs, L. L., Polcyn M. J., Mateus O., Schulp A., Ferguson K., Scotese C., Jacobs B. F., Strganac C., Vineyard D., Myers T. S., & Morais M. L. (2010).  Tectonic Drift, Climate, and Paleoenvironment of Angola Since the Cretaceous. AGU Fall Meeting Abstracts, 1:. 02., Jan Abstractjacobs_polcyn_mateus_et_al_2010_tectonic_drift_climate_and_paleoenvironment_of_angola_since_the_cretaceous.pdf

Africa is the only continent that now straddles arid zones located beneath the descending limbs of both the northern and southern Hadley cells, and it has done so since it became a distinct continent in the Early Cretaceous. Since that time, Africa has drifted tectonically some 12 degrees north and rotated approximately 45 degrees counterclockwise. This changing latitudinal setting and position of the landmass under the relatively stable Hadley Cells is manifested as southward migration of climatic zones over the past 132 million years. Data from kerogen, X-ray diffraction analysis of sedimentary matrix, carbon isotopes from shell samples and tooth enamel,new 40Ar/39Ar radiometric dates, pollen and plant macrofossils, and fossil vertebrates indicate a productive upwelling system adjacent to a coastal desert since the opening of the South Atlantic Ocean; however, the position of the coastal desert has migrated southward as Africa drifted north, resulting in today's Skeleton Coast and Benguela Current. This migration has had a profound effect on the placement of the West African coast relative to areas of high marine productivity and resulting extensive hydrocarbon deposits, on the placement of arid zones relative to the continent especially the Skeleton Coast desert, on the climatic history of the Congo Basin (which shows a Late Cretaceous decrease in aridity based on the relative abundance of analcime in the Samba core), and in reducing the southern temperate region of Africa from 17% of continental area during the Cretaceous to 2% today. We show here that these related geographic and environmental changes drove ecological and evolutionary adjustments in southern African floras and faunas, specifically with respect to the distribution of anthropoid primates, the occurrence of modern relicts such as the gnetalean Welwitschia mirabilis, endemism as in the case of ice plants, and mammalian adaption to an open environment as in springhares. Africa's tectonic drift through climate zones has been a first-order environmental determinant since the Early Cretaceous.

2009
Jacobs, L. L., Mateus O., Polcyn M. J., Schulp A. S., Scotese C. R., Goswami A., Ferguson K. M., Robbins J. A., Vineyard D. P., & Neto A. B. (2009).  Cretaceous paleogeography, paleoclimatology, and amniote biogeography of the low and mid-latitude South Atlantic Ocean. BULLETIN DE LA SOCIETE GEOLOGIQUE DE FRANCE. 180, 333-341., Jan: Univ Agostinho Neto, Univ Nova Lisboa, So Methodist Univ, Univ Texas Arlington, Museu Lourinha, Nat Hist Museum Abstractjacobs_mateus_et_al_2009_cretaceous_paleogeography_paleoclimatology_and_amniote_biogeography_of_the_south_atlantic_ocean_angola_africa_currents.pdf

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Jacobs, L. L., Mateus O., Polcyn M. J., Schulp A. S., Scotese C. R., Goswami A., Ferguson K. M., Robbins J. A., Vineyard D. P., & Neto A. B. (2009).  Cretaceous paleogeography, paleoclimatology, and amniote biogeography of the low and mid-latitude South Atlantic Ocean. Bulletin de la Societe Geologique de France. 180, 333-341., Number 4 Abstract
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