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We present a stratigraphic log supporting a preliminary magnetostratigraphy of a Tithonian–Berriasian section in Porto da Calada (Portugal). Based on biostratigraphy and reversed and normal magnetostratigraphy, the location of the Tithonian–Berriasian boundary is tentatively located at ca. 52 m, not in disagreement
with former proposals. Due to the occurrence of later remagnetization (diagenesis), the magnetostratigraphic definition of the Tithonian–Berriasian section at the Cabo Espichel (Portugal) location was not able to be established.

Sauropod dinosaurs were the largest animals ever to inhabit the land, with truly gigantic forms in at least three lineages1, 2, 3. Small species with an adult body mass less than five tonnes are very rare4, 5, and small sauropod bones generally represent juveniles. Here we describe a new diminutive species of basal macronarian sauropod, Europasaurus holgeri gen. et sp. nov., and on the basis of bone histology we show it to have been a dwarf species. The fossils, including excellent skull material, come from Kimmeridgian marine beds of northern Germany6, 7, and record more than 11 individuals of sauropods 1.7 to 6.2 m in total body length. Morphological overlap between partial skeletons and isolated bones links all material to the same new taxon. Cortical histology of femora and tibiae indicates that size differences within the specimens are due to different ontogenetic stages, from juveniles to fully grown individuals. The little dinosaurs must have lived on one of the large islands around the Lower Saxony basin8. Comparison with the long-bone histology of large-bodied sauropods suggests that the island dwarf species evolved through a decrease in growth rate from its larger ancestor.

We report here the addition of two rare mosasaur taxa to the Maastrichtian marine amniote fauna of Angola. The new specimens include a dentary fragment referable to the large carnivore Prognathodon saturator and an isolated tooth of the small durophage Carinodens belgicus. Both were recovered from Maastrichtian outcrops in southern Angola in 2011. Additionally, a complete posterior mandibular unit of a large mosasaur from the type Maastrichtian of The Netherlands, collected some time prior to 1879 and previously identified as ‘Mosasaurus giganteus’, is described and reassigned here to Prognathodon saturator; historical issues surrounding the taxonomic attribution of this specimen are clarified. The new material extends the known geographic distribution of Prognathodon saturator and Carinodens belgicus.

Here we describe a new species of the mosasaurine genus Prognathodon from the Maastrichtian of Namibe, Angola, on the basis of five specimens which represent most of the cranial skeleton including the diagnostic quadrate. Phylogenetic analysis shows this new taxon, P. kianda nov. sp., to be the sister taxon to all other species of Prognathodon. It is unique amongst Prognathodon in possessing a high marginal tooth count and relatively small pterygoid teeth. The tooth morphology in the new taxon is reminiscent of some species of the genus Liodon, allowing association of Liodon-like dentition with otherwise Prognathodon-like crania, and thus resolves the long-standing question of the phylogenetic affinities of Liodon.

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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.

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A partial plesiosauroid skull from the São Gião Formation (Toarcian, Lower Jurassic) of Alhadas, Portugal is re−evaluated and described as a new taxon, Lusonectes sauvagei gen. et sp. nov. It has a single autapomorphy, a broad triangular parasphenoid cultriform process that is as long as the posterior interpterygoid vacuities, and also a unique character combination, including a jugal that contacts the orbital margin, a distinct parasphenoid–basisphenoid suture exposed between the posterior interpterygoid vacuities, lack of an anterior interpterygoid vacuity, and striations on the ventral surface of
the pterygoids. Phylogenetic analysis of Jurassic plesiosauroids places Lusonectes as outgroup to “microcleidid elasmosaurs”, equivalent to the clade Plesiosauridae. Lusonectes sauvagei is the only diagnostic plesiosaur from Portugal, and the westernmost occurrence of any plesiosaurian in Europe.

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The end-Triassic extinction event (ETE), considered one of the ‘Big Five’ mass extinctions, marks a dividing line between early Mesozoic vertebrate assemblages, typically including abundant temnospondyls, basal synapsids and basal archosaurs, and ‘typical’ Mesozoic faunas dominated by dinosaurs, pterosaurs, crocodylomorphs, turtles and mammaliaforms.
Recent geochemical work has provided strong evidence that the ETE is synchronous with, and likely caused by, the emplacement of the Central Atlantic magmatic province (CAMP).
However, stratigraphic sections containing both terrestrial vertebrates and CAMP basalts are scarce, complicating attempts to examine terrestrial faunal changes during this extinction event. The Triassic–Jurassic Algarve Basin, southern Portugal, is an extensional rift basin

to-marginal marine red beds (the ‘Grés de Silves’ Group) interbedded with CAMP basalts.

bonebed from the interval ‘AB1’ of the Grés de Silves. Preliminary excavations yielded at least nine well-preserved temnospondyl individuals represented by partial to nearly complete skulls and disarticulated postcranial elements of juvenile to adult ages. Nearly all material appears to represent a single species of metoposaurid referable to the genus Metoposaurus, well known from the late Carnian–early Norian of Germany and Poland. A number of characters of the occiput and mandible suggest that the Algarve material may represent a new species. This new material provides new data on the diversity and paleogeographical distribution of the metoposaurids, a highly autapomorphic and peculiar group composed of large aquatic carnivores with a unique elongated but brevirostral skull. This taxon also provides

Horizon may be within or close to the late Carnian–early Norian. Additional bone-bearing horizons within the ‘Grés de Silves’ provide a rare opportunity to examine terrestrial faunal change in the lead-up to the ETE.

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.

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.

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.