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Lallensack,  J. N., Klein  H., Milàn  J., Wings  O., Mateus  O., & Clemmensen  L. B. (2017).  Sauropodomorph dinosaur trackways from the Fleming Fjord Formation of East Greenland: evidence for Late Triassic sauropods. AbstractWebsite
Pereira, B., Mateus O., Kullberg J. C., & Rocha R. (2017).  The geotouristic potential of the Oeste Region of Portugal. 14th European Geoparks Conference | Abstracts Book 167. 167., Ponta Delgadapereira_et_al_2017_geotouristic_oeste.pdf
Lallensack, J. N., Klein H., Milàn J., Wings O., Mateus O., & Clemmensen L. B. (2017).  Sauropodomorph dinosaur trackways from the Fleming Fjord Formation of East Greenland: Evidence for Late Triassic sauropods. Acta Palaeontologica Polonica. 62(4), 833-843. Abstractlallensack_et_al_2017_-_sauropodomorph_tracks_greenland.pdf

The Late Triassic (Norian–early Rhaetian) Fleming Fjord Formation of central East Greenland preserves a diverse fossil fauna, including both body and trace fossils. Trackways of large quadrupedal archosaurs, although already reported in 1994 and mentioned in subsequent publications, are here described and figured in detail for the first time, based on photogrammetric data collected during fieldwork in 2012. Two trackways can be referred to Eosauropus, while a third, bipedal trackway may be referred to Evazoum, both of which have been considered to represent sauropodomorph dinosaur tracks. Both the Evazoum and the Eosauropus trackways are distinctly larger than other trackways referred to the respective ichnogenera. The trackmaker of the best preserved Eosauropus trackway is constrained using a synapomorphy-based approach. The quadrupedal posture, the entaxonic pes structure, and five weight-bearing digits indicate a derived sauropodiform trackmaker. Other features exhibited by the tracks, including the semi-digitigrade pes and the laterally deflected unguals, are commonly considered synapomorphies of more exclusive clades within Sauropoda. The present trackway documents an early acquisition of a eusauropod-like pes anatomy while retaining a well-developed claw on pedal digit IV, which is reduced in eusauropods. Although unequivocal evidence for sauropod dinosaurs is no older than the Early Jurassic, the present trackway provides evidence for a possible Triassic origin of the group.

Mateus, O., Pereira B., Rocha R., & Kullberg J. C. (2018).  Aspiring Geopark Oeste in Portugal: scientific highlights and importance. 8th International Conference on UNESCO Global Geoparks. , 8-14 Sept., Adamello Brenta Geopark, Trentinomateus_et_al_2018_geopark_oeste.pdf
Park, J., Lee Y., Currie P. J., Kobayashi Y., Koppelhus E. B., Barsbold R., Lee S., Kim S., & Mateus O. (2019).  Three new skulls of the Late Cretaceous armored dinosaur Talarurus plicatospineus Maleev, 1952. Journal of Vertebrate Paleontology, Program and Abstracts. 165-166. Abstract
Park, J., Lee Y., Currie P. J., Kobayashi Y., Koppelhus E. B., Barsbold R., Lee S., Kim S., & Mateus O. (2019).  Three new skulls of the Late Cretaceous armored dinosaur Talarurus plicatospineus Maleev, 1952. Journal of Vertebrate Paleontology, Program and Abstracts. 165-166.park_et_al_2019_svp_abstract.pdf
Park, J. - Y., Lee Y. - N., Currie P. J., Kobayashi Y., Koppelhus E., Barsbold R., Mateus O., Lee S., & Kim S. - H. (2020).  Additional skulls of Talarurus plicatospineus (Dinosauria: Ankylosauridae) and implications for paleobiogeography and paleoecology of armored dinosaurs. Cretaceous Research. 108, 104340. Abstractpark_et_al_2020_additional_skulls_of_talarurus_plicatospineus_dinosauria_final.pdfWebsite

Three new additional skull specimens of Talarurus plicatospineus have been recovered from the Upper Cretaceous (Cenomanian–Santonian) Bayanshiree Formation, of Bayan Shiree cliffs, eastern Gobi Desert, Mongolia. The skulls feature unique characters such as an anteriorly protruded single internarial caputegulum, around 20 flat or concave nasal-area caputegulae surrounded by a wide sulcus, a vertically oriented elongate loreal caputegulum with a pitted surface, an elongate lacrimal caputegulum positioned above the posterodorsal border of the maxilla, two longitudinally arranged large frontoparietal caputegulae surrounded by smaller rhomboid caputegulae, small but elongate medial supraorbital caputegulae, a posterior supraorbital caputegulum that is four times larger than the anterior one, up to three transverse parallel grooves on the dorsal surface of the posterior supraorbital caputegulum, postocular caputegulae along the ventral to posterior rim of the orbit that extend almost to the anteroventral margin of the squamosal horn, a longitudinal furrow tapering towards the apex of the squamosal horn, a lateral nuchal caputegulum four to five times larger than other nuchal caputegulae, and a pterygovomerine keel with a ventral margin that is dorsally positioned to the alveolar ridge. The phylogenetic analysis result showed that Talarurus is sister to the clade that includes the derived Asian ankylosaurines (Saichania chulsanensis, Tarchia kielanae, and Zaraapelta nomadis). It also shows that there was dispersal of ankylosaurines from Asia into western North America before the Cenomanian. Moreover, the rostral differences between Talarurus and Tsagantegia, another ankylosaur from the same formation, suggest possible niche partitioning between these taxa.

Clemmensen, L. B., Kent D. V., Mau M., Mateus O., & Milàn J. (2020).  Triassic lithostratigraphy of the Jameson Land basin (central East Greenland), with emphasis on the new Fleming Fjord Group. Bulletin of the Geological Society of Denmark. 68, 95–132. Abstractclemmensen_et_al_2020_triassic_lithostratigraphy_of_the_jameson_land_basin.pdfWebsite

The lithostratigraphy of the Triassic deposits of the Jameson Land Basin in central East Greenland is revised. The new Scoresby Land Supergroup is now composed of the Wordie Creek, Pingo Dal, Gipsdalen and Fleming Fjord Groups. This paper only deals with the lithostratigraphy of the late Early-Late Triassic continental deposits of the latter three groups with emphasis on the vertebratebearing Fleming Fjord Group. The new Pingo Dal Group consists of three new formations, the Rødstaken, Paradigmabjerg and Klitdal Formations (all elevated from members), the new Gipsdalen Group consists of three new formations, the Kolledalen, Solfaldsdal (with the new Gråklint Member) and Kap Seaforth Formations (all elevated from members), and the new Fleming Fjord Group is subdivided into three new formations, the Edderfugledal, Malmros Klint and Ørsted Dal Formations (all elevated from members). The Edderfugledal Formation contains two cyclic bedded, lacustrine members, a lowermost Sporfjeld Member (elevated from beds), and an uppermost Pingel Dal Member (elevated from beds). The lacustrine red beds of the Malmros Klint Formation are not subdivided. The lacustrine and fluvial Ørsted Dal Formation contains three new members. In the eastern and central part of the basin, the formation is initiated by cyclic bedded, red lacustrine mudstones of the Carlsberg Fjord Member (elevated from beds), while in the northwestern part of the basin the lowermost part of the formation is composed of grey fluvial conglomerates and sandstones with subordinate red mudstones of the Bjergkronerne Member (elevated from beds). The uppermost part of the formations in most of the basin is composed of cyclic bedded, variegated lacustrine mudstones and grey to yellowish marlstones of the Tait Bjerg Member (elevated from beds). The sediments in the Fleming Fjord Group contain remains of a rich and diverse vertebrate fauna including dinosaurs, amphibians, turtles, aeotosaurs, pterosaurs, phytosaurs and mammaliaforms. Most vertebrate bones have been found in uppermost Malmros Klint Formation, and in the Carlsberg Fjord and Tait Bjerg Members. The Norian–early Rhaetian, lacustrine Fleming Fjord Group was deposited at about 41° N on the northern part of the supercontinent Pangaea. Lacustrine sedimentation was controlled by seasonal as well as longer-term (orbital) variation in precipitation. Precipitation was probably brought to the basin by southwesterly winds. The lacustrine sediments of the uppermost Fleming Fjord Group show deposition during increasingly humid conditions changing the lake environment from an ephemeral lake-steppe area to a perennial lake. This evolution of lake environment suggests a change from a winter-wet temperate climate to one with precipitation throughout the year.

López-Rojas, V., Mateus O., Milàn J., Wings O., Klein N., & Clemmensen L. B. (2021).  A new phytosaur from the Late Triassic of Jameson Land, Greenland. 3rd Palaeontological Virtual Congress. 207.: ISBN 978-84-09-36657-6 Abstractlopez_rojas_2021_pvc3_greenland.pdf


Clemmensen, L. B., Lindström S., Mateus O., Mau M., Milàn J., & Kent D. V. (2021).  A new vertebrate fossil-bearing layer in the Rhætelv Formation (Kap Stewart Group) of central East Greenland: evidence of a Hettangian marine incursion into the continental Jameson Land Basin. Lethaia. n/a, , Number n/a Abstractlet.12449.pdfWebsite

The Kap Stewart Group (Rhaetian-Sinemurian, Triassic–Early Jurassic) of the Jameson Land Basin in central East Greenland has traditionally been regarded as a strictly continental unit with delta and perennial lake sediments. New finds of plesiosaur bone remain in a thin storm deposited sandstone bed in the middle part of the Rhætelv Formation of the Kap Stewart Group, however, indicates a likely period of marine influence. At the study area at the eastern margin of the basin, the Rhætelv Formation is 300-m thick and overlies unconformably the Norian Fleming Fjord Group. The bone-bearing sandstone occurs 190 m above the base of the group and is closely associated with black laminated mudstones; palynological investigation of three samples from these mudstones indicates that they are of a younger Hettangian age. The Hettangian was a relatively short stage (201.3–199.5 Ma) and elsewhere characterized by two episodes of sea-level highstands. Assuming that the marine incursion in the Jameson land Basin evidenced by the plesiosaur fossil remains took place during the youngest of these sea-level highstands, the bone-bearing bed of the Rhætelv Formation can be dated to 200 Ma and thereby gives the first numerical age constraint of this hitherto poorly dated succession.

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.