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Although sauropod dinosaur bones are the most abundant vertebrate fossils found in the Upper Cretaceous Winton Formation of northeast Australia, only subadult and adult specimens have been described to date. Herein, we describe the first juvenile sauropod from Australia, derived from the Winton Formation (Cenomanian–lower Turonian). The preserved material belongs to a single individual and is sufficiently diagnostic to classify as a juvenile Diamantinasaurus matildae—the third specimen to be referred to the species. It also enables the identification of a new local autapomorphy for Diamantinasaurus: a distinct tuberosity on the medial surface of the scapula, posterior to the junction of the acromion and the distal blade. Nevertheless, several morphological changes are observable between the juvenile and the two adult skeletons of Diamantinasaurus matildae. These include less well-defined or entirely absent muscle attachment sites on the juvenile bones relative to the heavily scarred and rugose adult specimens. Overlapping elements between the juvenile and the two adult skeletons indicate allometric changes for Diamantinasaurus matildae throughout ontogeny, with limb bones growing at a more rapid proportional rate than other skeletal elements. Finally, we review the global record of juvenile sauropod remains, demonstrating that the growth patterns of sauropods vary greatly between taxa. Although titanosaurs display a range of isometry and allometry in the growth of individual bones, it appears that allometric growth was the primary pattern for this group. [ABSTRACT FROM AUTHOR]

Hudiesaurus sinojapanorum is a Late Jurassic sauropod from northwestern China that was erected on the basis of a cervicodorsal vertebra, four teeth, and a nearly complete forelimb. However, re-evaluation of this material, and comparisons with other taxa, indicate that there are few grounds for regarding these specimens as congeneric. Consequently, although we retain the vertebra as the holotype specimen of Hudiesaurus, the forelimb is assigned to a new taxon—Rhomaleopakhus turpanensis, gen. et sp. nov. The teeth previously referred to Hudiesaurus are poorly preserved but resemble those of several other 'core Mamenchisaurus-like taxa' (CMTs) from East Asia, such as Mamenchisaurus sinocanadorum. Phylogenetic analyses confirm that Hudiesaurus is a CMT and the sister taxon of Xinjiangtitan. Despite some uniquely shared features, their large size, and close geographic provenance, Hudiesaurus and Xinjiangtitan are retained as distinct genera based on their stratigraphic separation and numerous anatomical differences. Rhomaleopakhus is also shown to be a CMT in all analyses, being most closely related to Chuanjiesaurus and Analong. We link the convergent evolution of robust antebrachia and an enlarged olecranon in CMTs, titanosaurs, and some ornithischians (e.g., ceratopsids) to a more flexed orientation of the forearm, an enhanced role for the forelimb in locomotion, and an anterior shift in the whole-body center of mass. CMTs and titanosaurs potentially converged on a feeding strategy in which the ability to increase browse height via bipedal rearing was sacrificed in return for more efficient locomotion that improved travel between patchily distributed food sources. [ABSTRACT FROM AUTHOR]

Once a much more globally widespread crocodylian clade, Tomistominae is today represented by just one species, Tomistoma schlegelii (the false gharial), restricted to south-east Asia. Although tomistomine fossil occurrences are recognized from the early Eocene (∼55 Ma) onwards, their remains are often incomplete, making appropriate taxonomic classification within the group problematic. This is especially pertinent to several taxa from the Miocene of Europe, which were historically erected from fragmentary remains. Here we re-examine and describe four approximately contemporaneous taxa from Malta and Italy to determine their taxonomy and phylogenetic affinities: Melitosaurus champsoides, Tomistoma calaritanum, Tomistoma gaudense and Tomistoma lyceense. We place them into a phylogenetic analysis for the first time, comprising 70 taxa scored for 244 characters, several of which are revised or novel, and apply a number of character weighting strategies. Whereas 'Tomistoma lyceense' is deemed to be an indeterminate tomistomine, a unique combination of features confirms Melitosaurus champsoides, Tomistoma calaritanum and Tomistoma gaudense as three distinct species. These three taxa are recovered as derived tomistomines, with characters such as a posterior maxillary process between the lacrimal and nasal, large supratemporal fenestrae that are wider than long, and the posteromedial alignment of the last three premaxillary teeth, suggesting a close relationship with the approximately contemporaneous European taxa, Tomistoma lusitanica and Gavialosuchus eggenburgensis. It is unlikely that any of these species belong to Tomistoma, with the possibility that they can all be classified under Melitosaurus and Gavialosuchus. However, we retain them in open nomenclature pending reassessment of the remaining European Miocene tomistomines. Our taxonomic and phylogenetic revision helps to elucidate past tomistomine diversity in the Miocene of the Mediterranean region, prior to the group's extirpation, and is an important first step in resolving the complicated history of European tomistomine systematics. [ABSTRACT FROM AUTHOR]

The titanosaurian sauropod dinosaur Savannasaurus elliottorum is represented by a partial postcranial skeleton from the lower Upper Cretaceous (Cenomanian–lowermost Turonian) Winton Formation of Queensland, northeast Australia. Here, we present a detailed description of this specimen, as well as an emended diagnosis for this titanosaur. Savannasaurus elliottorum displays numerous character states that are generally regarded as plesiomorphic for Titanosauria, as well as several traits that are often regarded as apomorphic of that clade or a less inclusive subset thereof. Several features of Savannasaurus support a close relationship with the coeval Diamantinasaurus matildae, and this clade appears to occupy an early-branching position within Titanosauria. Relative to body size, the thoracic and abdominal breadth of Savannasaurus is greater than that seen in giant titanosaurs such as the contemporaneous South American lognkosaurians; however, this relative breadth is not quite as extreme as that of the small-bodied latest Cretaceous saltasaurines, or Opisthocoelicaudia skarzynskii. The possible advantages engendered by the barrel-shaped thorax, robust limbs, wide-gauge gait, and lack of hyposphene-hypantrum articulations are explored, and it is hypothesized that these traits were positively selected by the wet, temperate floodplain environment in which Savannasaurus lived. Greater stability and flexibility might have reduced the risk of bogging, and/or facilitated more expedient self-extraction from muddy waterholes. Similar environmental pressures acting upon other titanosaurian taxa or clades elsewhere might have led to the repeated independent development, or accentuation, of the bauplan regarded as 'typical' for the clade Titanosauria. This would explain the many observed convergences between Savannasaurus and Diamantinasaurus, and Saltasauridae. [ABSTRACT FROM AUTHOR]

Here we describe a new partial sauropod skeleton from the late Kimmeridgian (Late Jurassic) of the Lourinhã Formation, central west Portugal. The closely associated specimen comprises a complete tooth (with root), a fragment of cervical neural arch, an anterior chevron, and an almost complete right pectoral girdle and forelimb. The new sauropod,Zby atlanticus, n. gen. et sp., can be diagnosed on the basis of four autapomorphies, including a prominent posteriorly projecting ridge on the humerus at the level of the deltopectoral crest. Nearly all anatomical features indicate thatZbyis a non-neosauropod eusauropod. On the basis of several characters, including tooth morphology, extreme anteroposterior compression of the proximal end of the radius, and strong beveling of the lateral half of the distal end of the radius,Zbyappears to be closely related toTuriasaurus riodevensisfrom approximately contemporaneous deposits in eastern Spain. However, these two genera can be distinguished from each other by a number of features pertaining to the forelimb. Whereas previously described Late Jurassic Portuguese sauropods show close relationships with taxa from the contemporaneous Morrison Formation of North America, it appears that turiasaurians were restricted to Europe. All adult sauropods recovered in the Late Jurassic of Portugal thus far are very large individuals: it is possible that the apparent absence of small- or medium-sized adult sauropods might be related to the occupation of lower-browsing niches by non-sauropods such as the long-necked stegosaurMiragaia longicollum. [ABSTRACT FROM PUBLISHER]

Madtsoiidae is a speciose family of extinct snakes that achieved a wide Gondwanan and trans-Tethyan distribution by the Late Cretaceous, surviving until the late Pleistocene.Gigantophis garstini, the first and largest described madtsoiid, was recovered from the upper Eocene of Fayum, Egypt. The 20 vertebrae that constitute the syntype have only received brief description, hindering the referral of specimens to this taxon and our understanding of madtsoiid interrelationships in general. A detailed redescription of the syntype material demonstrates the validity ofGigantophis, based on two autapomorphies (including a strongly depressed neural canal in posterior trunk vertebrae) and a unique combination of characters. Referred material from the lower Paleocene of Pakistan differs significantly, and we restrictGigantophisto the middle–late Eocene of North Africa. Using a model of morphological variation in extant snakes, we estimate thatGigantophiswas 6.9 ± 0.3 m long. A phylogenetic analysis using the largest sample of putative madtsoiids (20 operational taxonomic units) and a revised and augmented matrix (148 characters) placesGigantophisas sister taxon to the latest Cretaceous Indian snakeMadtsoia pisdurensis. Whereas our topology might suggest that a dispersal route was present between India and North Africa in the latest Cretaceous–early Paleogene, an evaluation of putative dispersal routes leads us to conclude that the paleobiogeography of Madtsoiidae is best explained by a poorly sampled, earlier widespread distribution in Africa, Indo-Madagascar, and South America. In contrast, latest Cretaceous madtsoiid occurrences in Europe might be explicable by trans-Tethyan dispersal from Africa across the Apulian Route. SUPPLEMENTAL DATA—Supplemental materials are available for this article for free atwww.tandfonline.com/UJVP Citation for this article: Rio, J. P., and P. D. Mannion. 2017. The osteology of the giant snakeGigantophis garstinifrom the upper Eocene of North Africa and its bearing on the phylogenetic relationships and biogeography of Madtsoiidae. Journal of Vertebrate Paleontology. DOI: 10.1080/02724634.2017.1347179. [ABSTRACT FROM PUBLISHER]