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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.

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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.

The purpose of this application, under Articles 78.1 and 81.1 of the Code, is to replace Diplodocus longus Marsh, 1878 as the type species of the sauropod dinosaur genus Diplodocus by the much better represented D. carnegii Hatcher, 1901, due to the undiagnosable state of the holotype of D. longus (YPM 1920, a partial tail and a chevron). The holotype of D. carnegii, CM 84, is a well-preserved and mostly articulated specimen. Casts of it are on display in various museums around the world, and the species has generally been used as the main reference for studies of comparative anatomy or phylogeny of the genus. Both species are known from the Upper Jurassic Morrison Formation of the western United States. The genus Diplodocus is the basis for the family-level taxa diplodocinae Marsh, 1884, diplodocidae Marsh, 1884, diplodocimorpha Marsh, 1884 (Calvo & Salgado, 1995) and diplodocoidea Marsh, 1884 (Upchurch, 1995). It is also a specifier of at least 10 phylogenetic clades. With the replacement of D. longus by D. carnegii as type species, Diplodocus could be preserved as a taxonomic name with generally accepted content. Taxonomic stability of the entire clade diplodocoidea, and the proposed definitions of several clades within Sauropoda, could be maintained.

Ossified gastralia, clavicles and sternal ribs are known in a variety of reptilians, including dinosaurs. In sauropods, however, the identity of these bones is controversial. The peculiar shapes of these bones complicate their identification, which led to various differing interpretations in the past. Here we describe different elements from the chest region of diplodocids, found near Shell, Wyoming, USA. Five morphotypes are easily distinguishable: (A) elongated, relatively stout, curved elements with a spatulate and a bifurcate end resemble much the previously reported sauropod clavicles, but might actually represent interclavicles; (B) short, L-shaped elements, mostly preserved as a symmetrical pair, probably are the real clavicles, as indicated by new findings in diplodocids; (C) slender, rod-like bones with rugose ends are highly similar to elements identified as sauropod sternal ribs; (D) curved bones with wide, probably medial ends constitute the fourth morphotype, herein interpreted as gastralia; and (E) irregularly shaped elements, often with extended rugosities, are included into the fifth morphotype, tentatively identified as sternal ribs and/or intercostal elements. To our knowledge, the bones previously interpreted as sauropod clavicles were always found as single bones, which sheds doubt on the validity of their identification. Various lines of evidence presented herein suggest they might actually be interclavicles – which are single elements. This would be the first definitive evidence of interclavicles in dinosauromorphs. Previously supposed interclavicles in the early sauropodomorph Massospondylus or the theropods Oviraptor and Velociraptor were later reinterpreted as clavicles or furculae. Independent from their identification, the existence of the reported bones has both phylogenetic and functional significance. Their presence in non-neosauropod Eusauropoda and Flagellicaudata and probable absence in rebbachisaurs and Titanosauriformes shows a clear character polarity. This implicates that the ossification of these bones can be considered plesiomorphic for Sauropoda. The proposed presence of interclavicles in sauropods may give further support to a recent study, which finds a homology of the avian furcula with the interclavicle to be equally parsimonious to the traditional theory that furcula were formed by the fusion of the clavicles. Functional implications are the stabilizing of the chest region, which coincides with the development of elongated cervical and caudal vertebral columns or the use of the tail as defensive weapon. The loss of ossified chest bones coincides with more widely spaced limbs, and the evolution of a wide-gauge locomotor style.

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ABSTRACT Diplodocid sauropods had a unique skull morphology, with posteriorly retracted nares, an elongated snout, and anteriorly restricted, peglike teeth. Because of the lack of extant analogs in skull structure and tooth morphology, understanding their feeding strategy and diet has been difficult. Furthermore, the general rarity of sauropod skulls and the fragility of their facial elements resulted in a restricted knowledge of cranial anatomy, in particular regarding the internal surface of the facial skull. Here, we describe in detail a well-preserved diplodocid skull visible in medial view. Diagnostic features recognized in other skulls observable in lateral view, such as the extended contribution of the jugal to the antorbital fenestra, are obliterated in medial view due to extensive overlapping joints between the maxilla, jugal, quadratojugal, and the lacrimal. These overlapping joints permitted limited anterior sliding movement of the snout, which likely served as a kind of ?shock-absorbing? mechanism during feeding. Diplodocid skulls therefore seem to have evolved to alleviate stresses inflicted on the snout during backward movements of the head, as would be expected during branch-stripping or raking.ABSTRACT Diplodocid sauropods had a unique skull morphology, with posteriorly retracted nares, an elongated snout, and anteriorly restricted, peglike teeth. Because of the lack of extant analogs in skull structure and tooth morphology, understanding their feeding strategy and diet has been difficult. Furthermore, the general rarity of sauropod skulls and the fragility of their facial elements resulted in a restricted knowledge of cranial anatomy, in particular regarding the internal surface of the facial skull. Here, we describe in detail a well-preserved diplodocid skull visible in medial view. Diagnostic features recognized in other skulls observable in lateral view, such as the extended contribution of the jugal to the antorbital fenestra, are obliterated in medial view due to extensive overlapping joints between the maxilla, jugal, quadratojugal, and the lacrimal. These overlapping joints permitted limited anterior sliding movement of the snout, which likely served as a kind of ?shock-absorbing? mechanism during feeding. Diplodocid skulls therefore seem to have evolved to alleviate stresses inflicted on the snout during backward movements of the head, as would be expected during branch-stripping or raking.

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

Abstract
Late Jurassic dinosaur footprints were found on a coastline cliff in Lourinhã, Porto das Barcas, Lagido do Forno (coordinate 39°14.178’N, 9°20.397’W, Portugal) in June 2001. The locality is characterized by steep cliffs with high slopes that are composed of gray and red sandstones/ siltstones. The location belongs to the successions of Lusitanian Basin representing the Porto Novo Member of the Lourinhã Formation. Three natural infills of tridactyl tracks, possibly ascribed to ornithopod, a bipedal herbivore were found, representing a left foot movement, a right and a left one, respectively. Footprints are 300- 400mm wide and have a height of 330-360mm. The footprints are characterized by round fingers, which are elongated due to some degradation/ erosion. The footprints were collected from the field in 2001 and subsequently cleaned, consolidated and glued in the laboratory of the Museum of Lourinhã before being exhibited in a museum display. Stone matrix was removed and a consolidation product was applied, probably a polyvinyl acetate. The footprint with broken central digit was glued with an epoxy resin, Araldite. Both applied products were confirmed by analysis of μ- FTIR and both presented colour change and detachment surface problems. The footprints have been exposed in the palaeontology hall of the Museum of Lourinhã, Portugal from 2004 without climate controlling. These trace fossils form an important part of the palaeontological collection of Late Jurassic vertebrate fossils from Lourinhã Formation. Presently, it is considered a unique heritage in danger of disappearing due to high decay level of disaggregation of its geological structure. The footprints display several pathologies, such as “Blistering”, “Powdering”, “Exfoliation”’ as well as “Dirt”, “Fracture”’, “Inscriptions”, “Consolidants” and “Adhesives” and are now in very poor conditions. Laboratorial analysed were made to evaluate the presence of salts. Moreover a microclimatic study was conducted inside the museum to evaluate the influence of thermo-hygrometric parameters on the decay processes. The future interventions will depend on the results of consolidation trials that are currently under progress by using stone samples taken from the same layer and location from Porto das Barcas applying different commercial consolidation products.

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The purpose of this application, under Articles 78.1 and 81.1 of the Code, is to replace Diplodocus longus Marsh, 1878 as the type species of the sauropod dinosaur genus Diplodocus by the much better represented D. carnegii Hatcher, 1901, due to the undiagnosable state of the holotype of D. longus (YPM 1920, a partial tail and a chevron). The holotype of D. carnegii, CM 84, is a well-preserved and mostly articulated specimen. Casts of it are on display in various museums around the world, and the species has generally been used as the main reference for studies of comparative anatomy or phylogeny of the genus. Both species are known from the Upper Jurassic Morrison Formation of the western United States. The genus Diplodocus is the basis for the family-level taxa diplodocinae Marsh, 1884, diplodocidae Marsh, 1884, diplodocimorpha Marsh, 1884 (Calvo & Salgado, 1995) and diplodocoidea Marsh, 1884 (Upchurch, 1995). It is also a specifier of at least 10 phylogenetic clades. With the replacement of D. longus by D. carnegii as type species, Diplodocus could be preserved as a taxonomic name with generally accepted content. Taxonomic stability of the entire clade diplodocoidea, and the proposed definitions of several clades within Sauropoda, could be maintained.

In this paper we present a method for estimating soil pCO2 in ancient environments using the measured carbon-isotope values of pedogenic carbonates and plant-derived organic matter. The validity of soil pCO2 estimates proves to be highly dependent on the organic δ13C values used in the calculations. Organic matter should be sourced from the same paleosol profiles as sampled carbonates to yield the most reliable estimates of soil pCO2. In order to demonstrate the potential use of soil pCO2 estimates in paleoecological and paleoenvironmental studies, we compare samples from three Upper Jurassic localities. Soil pCO2 estimates, interpreted as a qualitative indicator of primary paleoproductivity, are used to rank the Late Jurassic terrestrial environments represented by the Morrison Formation in western North America, the informally named Lourinhã formation in Western Europe, and the Stanleyville Group in Central Africa. Because modern terrestrial environments show a positive correlation between primary productivity and faunal richness, a similar relationship is expected in ancient ecosystems. When the relative paleoproductivity levels inferred for each study area are compared with estimates of dinosaur generic richness, a positive correlation emerges. Both the Morrison and Lourinhã formations have high inferred productivity levels and high estimated faunal richness. In contrast, the Stanleyville Group appears to have had low primary productivity and low faunal richness. Paleoclimatic data available for each study area indicate that both productivity and faunal richness are positively linked to water availability, as observed in modern terrestrial ecosystems.

Clavicles and interclavicles are plesiomorphically present in Reptilia. However, several groups show reduction or even loss of these elements. Crocodylimorpha, e.g., lost the clavicles, whereas dinosaurs are generally interpreted to only preserve the clavicles, the theropod furcula representing an unique case of fused clavicles. In sauropods, reports of clavicles are relatively frequent in non-titanosauriforms. These elements are elongated, curved, and rather stout bones with a spatulate and a bifurcate end. However, they were always found as single bones, and differ from the relatively short and unbifurcated clavicles found articulated with the scapulae of basal sauropodomorphs.
Elements from the Howe Quarry (Late Jurassic; Wyoming, USA) shed new light on these interpretations. Besides the elongated, curved bones (herein named morphotype A), also pairs of symmetric, L-shaped bones were recovered (morphotype B), associated with diplodocid dorsal and cervical vertebrae. Elements resembling morphotype B - articulated between the scapulae - have recently been reported from a diplodocid found near Tensleep, Wyoming. Taphonomic evidence, as well as the fact that they were preserved in symmetrical pairs, therefore implies that morphotype B represents the true sauropod clavicles.
Contrary to earlier reports, morphotype A elements from the Howe Quarry, as well as of previously reported specimens show a symmetry plane following the long axis of the elements. It is thus possible that the morphotype A elements were single bones from the body midline. The only such element present in the pectoral girdle of tetrapods are the interclavicle and the furcula. Comparison with crocodilian and lacertiform interclavicles indicates that the bifurcate end of the sauropod elements might represent the reduced transverse processes of the anterior end, and the spatulate end would have covered the coracoids or sternal plates ventrally.
The presence of both clavicles and interclavicles in the pectoral girdle stiffens the anterior trunk, and enhances considerably its stability. Such an enforcement might have been needed in diplodocids due to the strong lateral forces induced to the fore-limbs by the posteriorly placed center of mass (due to shorter fore- than hind-limbs), as well as lateral movements of the enormously elongated necks and tails. The absence of clavicles and interclavicles in titanosauriforms coincides with the development of wide-gauge locomotion style.
The presence of interclavicles in sauropods supports the recently proposed homology of the furcula with the interclavicle, instead of representing fused clavicles. Interclavicles were thus not lost, but may have remained cartilaginous or have yet to be found in basal dinosauriforms.

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.

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Sauropod dinosaurs are well known for their massive sizes and long necks and tails. Among sauropods, flagellicaudatan dinosaurs are characterized by extreme tail elongation, which has led to hypotheses regarding tail function, often compared to a whip. Here, we analyse the dynamics of motion of a 3D model of an apatosaurine flagellicaudatan tail using multibody simulation and quantify the stress-bearing capabilities of the associated soft tissues. Such an elongated and slender structure would allow achieving tip velocities in the order of 30 m/s, or 100 km/h, far slower than the speed of sound, due to the combined effect of friction of the musculature and articulations, as well as aerodynamic drag. The material properties of the skin, tendons, and ligaments also support such evidence, proving that in life, the tail would not have withstood the stresses imposed by travelling at the speed of sound, irrespective of the conjectural ‘popper’, a hypothetical soft tissue structure analogue to the terminal portion of a bullwhip able to surpass the speed of sound.