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

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

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.

Xing, L., Lockley M. G., Marty D., Zhang J., Wang Y., Klein H., McCrea R. T., Buckley L. G., Belvedere M., Mateus O., Gierli?ski G. D., Piñuela L., Persons W. S., Wang F., Ran H., Dai H., & Xie X. (2015).  An ornithopod-dominated tracksite from the lower Cretaceous Jiaguan Formation (Barremian-Albian) of Qijiang, South-Central China: New discoveries, ichnotaxonomy, preservation and palaeoecology. PLoS ONE. 10, , Number 10 Abstract
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Xing, L., Lockley M. G., Marty D., Zhang J., Wang Y., Klein H., McCrea R. T., Buckley L. G., Belvedere M., Mateus O., Gierliński G. D., Piñuela L., Persons, IV S. W., Wang F., Ran H., Dai H., & Xie X. (2015).  An Ornithopod-Dominated Tracksite from the Lower Cretaceous Jiaguan Formation (Barremian–Albian) of Qijiang, South-Central China: New Discoveries, Ichnotaxonomy, Preservation and Palaeoecology. PLoS ONE. 10, e0141059., 10, Number 10: Public Library of Science Abstractlida_et_al_2015_an_ornithopod-dominated_tracksite_from_the.pdfWebsite

The historically-famous Lotus Fortress site, a deep 1.5–3.0-meter-high, 200-meter-long horizonal notch high up in near-vertical sandstone cliffs comprising the Cretaceous Jiaguan Formation, has been known since the 13th Century as an impregnable defensive position. The site is also extraordinary for having multiple tetrapod track-bearing levels, of which the lower two form the floor of part of the notch, and yield very well preserved asseamblages of ornithopod, bird (avian theropod) and pterosaur tracks. Trackway counts indicate that ornithopods dominate (69%) accounting for at least 165 trackmakers, followed by bird (18%), sauropod (10%), and pterosaur (3%). Previous studies designated Lotus Fortress as the type locality of Caririchnium lotus and Wupus agilis both of which are recognized here as valid ichnotaxa. On the basis of multiple parallel trackways both are interpreted as representing the trackways of gregarious species. C. lotus is redescribed here in detail and interpreted to indicate two age cohorts representing subadults that were sometimes bipedal and larger quadrupedal adults. Two other previously described dinosaurian ichnospecies, are here reinterpreted as underprints and considered nomina dubia. Like a growing number of significant tetrapod tracksites in China the Lotus Fortress site reveals new information about the composition of tetrapod faunas from formations in which the skeletal record is sparse. In particular, the site shows the relatively high abundance of Caririchium in a region where saurischian ichnofaunas are often dominant. It is also the only site known to have yielded Wupus agilis. In combination with information from other tracksites from the Jiaguan formation and other Cretaceous formations in the region, the track record is proving increasingly impotant as a major source of information on the vertebrate faunas of the region. The Lotus Fortress site has been developed as a spectacular, geologically-, paleontologically- and a culturally-significant destination within Qijiang National Geological Park.

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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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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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.

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.

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, 833–843., Number 4 Abstract
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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
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Tschopp, E., Mateus O., Kosma R., Sander M., Joger U., & Wings O. (2014).  A specimen-level cladistic analysis of Camarasaurus (Dinosauria, Sauropoda) and a revision of camarasaurid taxonomy. Journal of Vertebrate Paleontology. Program and Abstracts, 2014, 241-242.tschopp_et_al._2014_a_specimen-level_cladistic_analysis_of_camarasaurus.pdf
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.

Allain, R., Taquet P., Battail B., Dejax J., Richir P., Veran M., Limon-Duparcmeur F., Vacant R., Mateus O., Sayarath P., Khenthavong B., & Phouyavong S. (1999).  Un nouveau genre de dinosaure sauropode de la formation des Gres superieurs (Aptien-Albien) du Laos. Comptes Rendus de l'Academie des Sciences - Series IIA - Earth and Planetary Science. 329, 609-616., oct, Number 8 Abstractallain_taquet_battail_dejax_richir_mateus_et_al_1999_un_nouveau_genre_de_dinosaure_sauropode_de_la_formation_des_gres_superieurs_aptien-albien_du_laos.pdfWebsite

The partly-articulated postcranial remains of two sauropod skeletons recently found in Tang Vay (Savannakhet Province, Laos) are assigned to the species Tangvayosaurus hoffeti (nov. gen., nov. sp.). The derived characters present in the new material confirm the presence of titanosaurs in South East Asia at the end of the Early Cretaceous, but are not consistent with its placement within Titanosaurus genus as first done by Hoffet in 1942. All of the material relative to this species is therefore referred to a new genus: Tangvayosaurus. Tangvayosaurus and the Thai genus Phuwiangosaurus have strong affinities and are considered as primitive titanosaurs.

Allain, R., Taquet P., Battail B., Dejax J., Richir P., Véran M., Limon-Duparcmeur F., Vacant R., Mateus O., Sayarath P., Khenthavong B., & Phouyavong S. (1999).  Un nouveau genre de dinosaure sauropode de la formation des Grès supérieurs (Aptien-Albien) du Laos. Comptes Rendus de l{\textquotesingle}Académie des Sciences - Series {IIA} - Earth and Planetary Science. 329, 609–616., oct, Number 8: Elsevier {BV} AbstractWebsite
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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.

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.