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A forelimb of a new sauropod dinosaur (Angolatitan adamastor n. gen. et sp.) from the Late Turonian of Iembe (Bengo Province) represents the first dinosaur discovery in Angola, and is one of the few occurrences of sauropod dinosaurs in sub-Saharan Africa collected with good chronological controls. The marginal marine sediments yielding the specimen are reported to be late Turonian in age and, thus it represents a non-titanosaurian sauropod in sub-Saharan Africa at a time taken to be dominated by titanosaurian forms. Moreover, Angolatitan adamastor is the only basal Somphospondyli known in the Late Cretaceous which implies in the existence of relict forms in Africa.

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

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

ABSTRACTThe fossil record of post-Paleozoic lungfishes in Greenland is currently restricted to a few brief reports of isolated and undetermined tooth plates coming from the uppermost Fleming Fjord Formation (late Norian) in Jameson Land, central East Greenland. Here, we describe Ceratodus tunuensis, sp. nov., a new dipnoan from a thin bed of calcareous lake mudstone from the ?rsted Dal Member of the Fleming Fjord Formation. The Ceratodus fossil record indicates that during the Late Triassic, this genus was restricted to the middle latitudes of the Northern Hemisphere. This record matches previous paleobiogeographical analyses and indicates that terrestrial biota during the Late Triassic was strongly influenced by paleolatitude.Citation for this article: Agnolin, F. L., O. Mateus, J. Milàn, M. Marzola, O. Wings, J. Schulz Adolfssen, and L. B. Clemmensen. 2018. Ceratodus tunuensis, sp. nov., a new lungfish (Sarcopterygii, Dipnoi) from the Upper Triassic of central East Greenland. Journal of Vertebrate Paleontology. DOI: 10.1080/02724634.2018.1439834.

A large collection of vertebrate coprolites from black lacustrine shales in the Late Triassic (Rhaetian–Sinemurian) Kap Stewart Formation, East Greenland is examined with regard to internal and external morphology, prey inclusions, and possible relationships to the contemporary vertebrate fauna. A number of the coprolites were mineralogically examined by X-ray diffraction (XRD), showing the primary mineral composition to be apatite, clay minerals, carbonates and, occasionally, quartz in the form of secondary mineral grains. The coprolite assemblage shows multiple sizes and morphotypes of coprolites, and different types of prey inclusions, demonstrating that the coprolite assemblage originates from a variety of different producers.Supplementary material: A description of the size, shape, structure, texture, contents and preservation of the 328 specimens is available at https://doi.org/10.6084/m9.figshare.c.2134335

A large collection of vertebrate coprolites from black lacustrine shales in the Late Triassic (Rhaetian–Sinemurian) Kap Stewart Formation, East Greenland is examined with regard to internal and external morphology, prey inclusions, and possible relationships to the contemporary vertebrate fauna. A number of the coprolites were mineralogically examined by X-ray diffraction (XRD), showing the primary mineral composition to be apatite, clay minerals, carbonates and, occasionally, quartz in the form of secondary mineral grains. The coprolite assemblage shows multiple sizes and morphotypes of coprolites, and different types of prey inclusions, demonstrating that the coprolite assemblage originates from a variety of different producers.Supplementary material: A description of the size, shape, structure, texture, contents and preservation of the 328 specimens is available at https://doi.org/10.6084/m9.figshare.c.2134335

Several well preserved clutches of dinosaurs have been discovered in the upper Kimmeridgian/ Tithonian of Lourinhã (Estramadur Province, Portugal). Some eggs of one clutch contained embryo elements of a theropod dinosaur. The egg-shell resembles that of eggs which have been discovered in the Upper Jurassic of Colorado

Theropod teeth are particularly abundant in the fossil record and frequently reported in the literature. Yet, the dentition of many theropods has not been described comprehensively, omitting details on the denticle shape, crown ornamentation and enamel texture. This paucity of information has been particularly striking in basal clades, thus making identification of isolated teeth difficult, and taxonomic assignments uncertain. We here provide a detailed description of the dentition of Megalosauridae, and a comparison to and distinction from superficially similar teeth of all major theropod clades. Megalosaurid dinosaurs are characterized by a mesial carina facing mesiolabially in most mesial teeth, centrally positioned carinae on both most mesial and lateral crowns, a mesial carina terminating above the cervix, and short to well-developed interdenticular sulci between distal denticles. A discriminant analysis performed on a dataset of numerical data collected on the teeth of 62 theropod taxa reveals that megalosaurid teeth are hardly distinguishable from other theropod clades with ziphodont dentition. This study highlights the importance of detailing anatomical descriptions and providing additional morphometric data on teeth with the purpose of helping to identify isolated theropod teeth in the future.

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A synthesis on the state of art on dinosaur knowledge in Portugal is presented. The following genera have been recognized: Ceratosaurus, Torvosaurus, Lourinhanosaurus, Allosaurus, cf. Compsognathus, Stokesosaurus, cf. Richardoestesia, cf. Archaeopteryx, Euronychodon, cf. Paronychodon, Dinheirosaurus, Lourinhasaurus, Lusotitan, cf. Pleurocoelus, Lusitanosaurus, Dacentrurus, Dracopelta, Phyllodon, Hypsilophodon, Alocodon, Trimucrodon, Draconyx, Iguanodon, and Taveirosaurus. Most are from Late Jurassic localities at the Lourinhã area and Guimarota. A new genus, Lusotitan, is here raised to include the Late Jurassic ‘Brachiosaurus’ atalaiensis. Lower Cretaceous until Cenomanian material is scarce, except for dinosaur footprints. An interesting Late-Cretaceous, mostly small dinosaur association has been collected between Aveiro and Taveiro.

Isolated theropod teeth are some of the most common fossils in the dinosaur fossil record and are continually reported in the literature. Recently developed quantitative methods have improved our ability to test the affinities of isolated teeth in a repeatable framework. But in most studies, teeth are diagnosed on qualitative characters. This can be problematic because the distribution of theropod dental characters is still poorly documented, and often restricted to one lineage. To help in the identification of isolated theropod teeth, and to more rigorously evaluate their taxonomic and phylogenetic potential, we evaluated dental features in two ways. We first analyzed the distribution of 34 qualitative dental characters in a broad sample of taxa. Functional properties for each dental feature were included to assess how functional similarity generates homoplasy. We then compiled a quantitative data matrix of 145 dental characters for 97 saurischian taxa. The latter was used to assess the degree of homoplasy of qualitative dental characters, address longstanding questions on the taxonomic and biostratigraphic value of theropod teeth, and explore the major evolutionary trends in the theropod dentition.

In smaller phylogenetic datasets for Theropoda, dental characters exhibit higher levels of homoplasy than non-dental characters, yet they still provide useful grouping information and optimize as local synapomorphies of smaller clades. In broader phylogenetic datasets, the degree of homoplasy displayed by dental and non-dental characters is not significantly different. Dental features on crown ornamentations, enamel texture and tooth microstructure have significantly less homoplasy than other dental features and can be used to identify many theropod taxa to ‘family’ or ‘sub-family’ level, and some taxa to genus or species. These features should, therefore, be a priority for investigations seeking to classify isolated teeth.

Our observations improve the taxonomic utility of theropod teeth and in some cases can help make isolated teeth useful as biostratigraphic markers. This proposed list of dental features in theropods should, therefore, facilitate future studies on the systematic paleontology of isolated teeth.

A new ornithopod dinosaur is described here under the name of Draconyx loureiroi n. gen., n. sp. on teeth, caudal vertebrae, forelimb, hindlimb, and foot material that were found in association in the Late Jurassic-Tithonian of Lourinhã, Portugal. Draconyx is a Camptosauridae related to Camptosaurus.

The non-avian saurischians that have associated eggshells and embryos are represented only by the sauropodomorph Massospondylus and Coelurosauria (derived theropods), thus missing the basal theropod representatives. We report a dinosaur clutch containing several crushed eggs and embryonic material ascribed to the megalosaurid theropod Torvosaurus. It represents the first associated eggshells and embryos of megalosauroids, thus filling an important phylogenetic gap between two distantly related groups of saurischians. These fossils represent the only unequivocal basal theropod embryos found to date. The assemblage was found in early Tithonian fluvial overbank deposits of the Lourinhã Formation in West Portugal. The morphological, microstructural and chemical characterization results of the eggshell fragments indicate very mild diagenesis. Furthermore, these fossils allow unambiguous association of basal theropod osteology with a specific and unique new eggshell morphology.

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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.

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.

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.

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.

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.

ABSTRACT We report here a new elasmosaurid from the early Maastrichtian at Bentiaba, southern Angola. Phylogenetic analysis places the new taxon as the sister taxon to Styxosaurus snowii, and that clade as the sister of a clade composed of (Hydrotherosaurus alexandrae (Libonectes morgani + Elasmosaurus platyurus)). The new taxon has a reduced dorsal blade of the scapula, a feature unique amongst elasmosaurids, but convergent with cryptoclidid plesiosaurs, and indicates a longitudinal protraction-retraction limb cycle rowing style with simple pitch rotation at the glenohumeral articulation. Morphometric phylogenetic analysis of the coracoids of 40 eosauropterygian taxa suggests that there was a broad range of swimming styles within the clade.