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The first paleontological works on Mesozoic vertebrates from Portugal, carried out from the end of the 19th and the first half of the 20th century, provided the discovery of significant collections of vertebrate fossils. These collections are particularly relevant because they include several specimens collected from different regions of the Lusitanian Basin (some of the sites are currently inaccessible), whose fossil record is poorly known. Theropod remains are relatively scarce and generally consist of fragmentary material, mostly assigned to the megalosaurid Megalosaurus from the Middle Jurassic of England, the first dinosaur to be named and a "wastebasket" taxon used by many scientists to identify theropod material. The studied fossils mostly consist of isolated teeth and vertebrae collected from Upper Jurassic levels of the coastal region, with also some material from Lower and Upper Cretaceous strata from the central and northern sectors of the Lusitanian Basin. Here specimens attributed to Megalosaurus from different Portuguese institutions are reviewed and their taxonomic affinity and stratigraphic context are updated. Most specimens actually belong to different theropod groups, including several isolated teeth from different Upper Jurassic localities here assigned to Ceratosaurus, Torvosaurus, andAllosaurus, as well as an isolated tooth from the Lower Cretaceous that is attributed to an indeterminate allosauroid. Other theropod remains consist mostly of vertebral fragments of indeterminate avetheropods and allosau-roids. Elements of other dinosaur groups are also represented, including a few vertebrae here referred to stegosaurians and iguanodontians, as well as a vertebra and some appendicular remains attributed to sauropods. Two vertebrae assigned to thalattosuchians were also identified. The study of this collection allows to better characterize the diversity of Late Jurassic dinosaur faunas from different areas of the Lusitanian Basin and provides some data on the poorly known Cretaceous fossil record of theropods from Portugal. [ABSTRACT FROM AUTHOR]

Rebbachisauridae is a clade of sauropod dinosaurs whose maximum diversification and abundance are known from the Cretaceous of South America. We describe an anterior caudal vertebra, MDPA-Pv 007, from the Upper Cretaceous of Argentine Patagonia, whose characters allow it to be referred to this clade. Also, two phylogenetic analyses reinforce the referral of the new material more exclusively to Rebbachisaurinae. We analyze pneumatic structures using the first CT scans of a caudal element of a rebbachisaurid. The excellent preservation of MDPA-Pv 007, combined with CT images, allows us to document external fossae and foramina that connect to larger internal chambers, constituting unambiguous evidence of pneumaticity. The centrum of MDPA-Pv 007 is camerate, with large interconnected internal chambers; this is accompanied by a neural arch with wide and deep fossae. Caudal pneumaticity has a complex phylogenetic distribution among neosauropods. This feature may have evolved independently in diplodocoids and titanosauriforms, or it could be ancestral for Neosauropoda but secondarily lost in a few lineages. Future investigations, taking advantage of new technologies, will provide insights into the phylogenetic distribution and paleobiological implications of pneumaticity in sauropod dinosaurs and other fossil archosaurs. [ABSTRACT FROM AUTHOR]

Pneumatic dorsal ribs are known for many sauropods, but to date costal pneumaticity has received relatively little attention. In particular, the pneumatic ribs of the holotype specimen of Brachiosaurus altithorax have been largely overlooked, although they present a unique configuration of pneumatic features. One rib, with a pneumatic foramen some distance down the shaft, was briefly described and illustrated in the early 20th century by Elmer S. Riggs. A second rib with a pneumatic foramen in the tuberculum of the rib has not previously been described or illustrated. This previously undescribed foramen is similar in location to those in some dorsal ribs of Brontosaurus excelsus and Giraffatitan brancai, but differs from them in both size and shape. The contrasting sites of costal pneumaticity in the holotype individual of Brachiosaurus altithorax emphasize the generally opportunistic mode of postcranial pneumatization, in both sauropods and other ornithodirans, but conform to models of pneumatization following vascularization. [ABSTRACT FROM AUTHOR]

A new gigantic titanosaur Bustingorrytitan shiva gen. et sp. nov. is described. The four specimens upon which this species is erected come from Neuquén Province, Argentina, from levels of the Huincul Formation (Cenomanian). Bustingorrytitan shiva gen. et sp. nov. exhibits some autapomorphic characters such as posterior dorsal vertebrae with spinodiapophyseal laminae bifurcated in two, very well developed anterior and posterior spinodiapophyseal lamina rami, which limit a deep, vertical, socket-like fossa; posterior dorsal neural arches with forked centropostzygapophyseal laminae; hyposphene in anterior caudal vertebrae; humerus with deltopectoral crest strongly expanded distally; and femur with a low longitudinal crest on the lateromedial half of the anterior face, bifurcated in two minor crests, which are directed to their respective condyles. The phylogenetic analysis performed recovers B. shiva gen. et sp. nov. as a lithostrotian, the sister taxon of Saltasauridae. The estimated body mass is 67.297 metric tons (with a standard error of ±17.228), which makes B. shiva gen. et sp. nov. one of the largest sauropods ever recorded. The record of this new sauropod corroborates the idea that gigantism (evolution of forms over the 50 metric tons) would have evolved many times within Eutitanosauria. [ABSTRACT FROM AUTHOR]

Two anterior caudal vertebrae from apparently a single individual from the Callovian (Middle Jurassic) marine deposits of the Podosinki Formation at Peski Quarry near Moscow, Russia, are attributed by the phylogenetic analyses of two independent datasets to the sauropod clade Diplodocoidea. Morphologically, these vertebrae differ from the anterior caudals of Diplodocidae and Rebbachisauridae, but are similar to those of Dicraeosauridae. This finding is in line with a recent discovery of the dicraeosaurid sauropod Lingwulong from the late Early–early Middle Jurassic of China, and suggests earlier diversification of the main neosauropod lineages and Asiatic origin for Dicraeosauridae. The Peski sauropod is the first Jurassic terrestrial vertebrate from the Fennoscandian landmass. Diplodocoid sauropods likely dispersed to this land massive before the Bathonian, when it was still connected with Asia. [ABSTRACT FROM AUTHOR]

Currently, there are two sauropod taxa known from the Upper Cretaceous (Maastrichtian) Nemegt Formation of Gobi Desert, Mongolia: Nemegtosaurus from the Nemegt locality and Opisthocoelicaudia from the Altan Uul IV locality. Both taxa are represented by not overlapping elements (skull and partial postcranial skeleton respectively), which arises question on their possible synonymy. Five articulated sauropod dorsal vertebrae (PIN 3837/P821, dorsals 6-10) were found in 1949 by the Mongolian Expedition of the Academy of Sciences of the USSR at the Nemegt locality. This specimen is similar to Opisthocoelicaudia in having a strong ventral ridge on dorsal centra, a low neural arch which is anteroposteriorly narrowest at the junction with the centrum and widens dorsally, and lack of hyposphene-hypantrum articulations. PIN 3837/P821 differs from Opisthocoelicaudia by having the less dorsoventrally flattened dorsal centra, a shallow ventral concavity of dorsal centra in lateral view, a vertical posterior centrodiapophyseal lamina (pcdl) in dorsals 8 and 9, a postzygodiapophyseal lamina (podl) that roofs the centrodiapophyseal fossa (pocdf), and strongly developed accessory laminae within the parapophyseal centrodiapophyseal fossa (pacdf). The sauropod femora from Nemegt Formation differ from the femur of Opisthocoelicaudia by the medial condyle extending more distally compared with the lateral condyle. Most likely these femora and PIN 3837/P821 belong to Nemegtosaurus, which would make this taxon distinct from Opisthocoelicaudia by discussed characters of dorsal vertebrae and femur. [ABSTRACT FROM AUTHOR]

Despite being globally widespread and abundant throughout much of the Mesozoic, the early record of sauropod dinosaur evolution is extremely poor. As such, any new remains can provide significant additions to our understanding of this important radiation. Here, we describe two sauropod middle cervical vertebrae from a new Early Jurassic locality in the Haute Moulouya Basin, Central High Atlas of Morocco. The possession of opisthocoelous centra, a well-developed system of centrodiapophyseal laminae, and the higher elevation of the postzygapophyses relative to the prezygapophyses, all provide strong support for a placement within Sauropoda. Absence of pneumaticity indicates non-neosauropod affinities, and several other features, including a tubercle on the dorsal margin of the prezygapophyses and an anteriorly slanting neural spine, suggest close relationships with various basal eusauropods, such as the Middle Jurassic taxa Jobaria tiguidensis and Patagosaurus fariasi. Phylogenetic analyses also support a position close to the base of Eusauropoda. The vertebrae differ from the only other Early Jurassic African sauropod dinosaurs preserving overlapping remains (the Moroccan Tazoudasaurus naimi and South African Pulanesaura eocollum), as well as stratigraphically younger taxa, although we refrain from erecting a new taxon due to the limited nature of the material. These new specimens represent one of the earliest eusauropod taxa and are an important additional data point for elucidating the early evolution of the clade. [ABSTRACT FROM AUTHOR]

Many titanosaurian dinosaurs are known only from fragmentary remains, making comparisons between taxa difficult because they often lack overlapping skeletal elements. This problem is particularly pronounced for the exceptionally large-bodied members of this sauropod clade. Dreadnoughtus schrani is a well-preserved giant titanosaurian from the Upper Cretaceous (Campanian-Maastrichtian) Cerro Fortaleza Formation of southern Patagonia, Argentina. Numerous skeletal elements are known for Dreadnoughtus, including seven nearly complete dorsal vertebrae and a partial dorsal neural arch that collectively represent most of the dorsal sequence. Here we build on our previous preliminary description of these skeletal elements by providing a detailed assessment of their serial positional assignments, as well as comparisons of the dorsal vertebrae of Dreadnoughtus with those of other exceptionally large-bodied titanosaurians. Although the dorsal elements of Dreadnoughtus probably belong to two individuals, they exhibit substantial morphological variation that suggests that there is minimal, if any, positional overlap among them. Dreadnoughtus therefore preserves the second-most complete dorsal vertebral series known for a giant titanosaurian that has been described in detail, behind only that of Futalognkosaurus. The dorsal sequence of Dreadnoughtus provides valuable insight into serial variation along the vertebral column of these enormous sauropods. Such variation includes the variable presence of divided spinodiapophyseal laminae and associated spinodiapophyseal fossae. Given that dorsal vertebrae are the only elements that overlap between known remains of most giant titanosaurian taxa, the dorsal series of Dreadnoughtus provides a means to directly compare the morphologies of these sauropods. The dorsal vertebrae of Dreadnoughtus and Futalognkosaurus have dorsoventrally narrow transverse processes, unlike the condition in Puertasaurus. Further, Dreadnoughtus and Argentinosaurus have ventromedially inclined prezygapophyses, whereas Futalognkosaurus has almost horizontal prezygapophyses. The continued inclusion of new, well-represented skeletons of titanosaurians such as Dreadnoughtus in phylogenetic and functional morphological studies will aid in deciphering the interrelationships and paleobiology of Titanosauria. [ABSTRACT FROM AUTHOR]

This paper reports the use of FEA (Finite Element Analysis) to model dinosaur tracks. Satisfactory reproductions of sauropod ichnites were simulated using 3D numerical models of the elasto-plastic behaviour of soils. Though the modelling was done of ichnites in situ at the Miraflores I tracksite (Soria, Spain), the methodology could be applied to other tracksites to improve their ichnological interpretation and better understand how the type and state of the trodden sediment at the moment the track is created is a fundamental determinant of the morphology of the ichnite. The results obtained explain why the initial and commonly adopted hypothesis--that soft sediments become progressively more rigid and resistant at depth--is not appropriate at this tracksite. We explain why it is essential to consider a more rigid superficial layer (caused by desiccation) overlying a softer layer that is extruded to form a displacement rim. Adult sauropods left trackways behind them. These tracks could be filled up with water due to phreatic level was close to the ground surface. The simulation provides us with a means to explain the differences between similar tracks (of different depths; with or without displacement rims) in the various stratigraphic layers of the tracksite and to explain why temporary and variable conditions of humidity lead to these differences in the tracks. The simulations also demonstrate that track depth alone is insufficient to differentiate true tracks from undertracks and that other discrimination criteria need to be taken into account. The scarcity of baby sauropod tracks is explained because they are shallow and easily eroded. [ABSTRACT FROM AUTHOR]

Several types of pathological bony overgrowth are known from various dinosaur taxa but, except for stress fractures, are rarely reported from appendicular elements. Herein we describe pathological manual and pedal phalanges of a camarasaurid sauropod (SMA 0002), which show features rarely recognised in non-avian dinosaurs. They include lateral osteophytes and smoothing of phalangeal articular surfaces, a deep pit, proximal enthesophytes in pedal unguals, distal overgrowth associated with a fracture, and a knob-like overgrowth lateral to the distal condyles of a pedal phalanx. Their causes were assessed by means of visual examination, CT scans, and bone histology, where possible. The lateral osteophytes are interpreted as symptoms of osteoarthritis. The ossified tendon insertions in the unguals are most probably the result of prolonged, heavy use of the pedal claws, possibly for scratch-digging. The distal overgrowth is interpreted to have developed due to changed stress regimes, and to be the cause for the fracture. The deep pit represents most likely a case of osteochondrosis, whereas the knob-like overgrowth likely represents a post-traumatic phenomenon not previously reported in dinosaurs. The study confirms that a rigorous assessment of pathologies can yield information about behaviour in long-extinct animals. [ABSTRACT FROM AUTHOR]