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Bite marks provide direct evidence for trophic interactions and competition in the fossil record. However, variations in paleoecological dynamics, such as trophic relationships, feeding behavior, and food availability, govern the frequency of these traces. Theropod bite marks are particularly rare, suggesting that members of this clade might not often focus on bone as a resource, instead preferentially targeting softer tissues. Here, we present an unusually large sample of theropod bite marks from the Upper Jurassic Mygatt-Moore Quarry (MMQ). We surveyed 2,368 vertebrate fossils from MMQ in this analysis, with 684 specimens (28.885% of the sample) preserving at least one theropod bite mark. This is substantially higher than in other dinosaur-dominated assemblages, including contemporaneous localities from the Morrison Formation. Observed bite marks include punctures, scores, furrows, pits, and striations. Striated marks are particularly useful, diagnostic traces generated by the denticles of ziphodont teeth, because the spacing of these features can be used to provide minimum estimates of trace maker size. In the MMQ assemblage, most of the striations are consistent with denticles of the two largest predators known from the site: Allosaurus and Ceratosaurus. One of the bite marks suggests that a substantially larger theropod was possibly present at the site and are consistent with large theropods known from other Morrison Formation assemblages (either an unusually large Allosaurus or a separate, large-bodied taxon such as Saurophaganax or Torvosaurus). The distribution of the bite marks on skeletal elements, particularly those found on other theropods, suggest that they potentially preserve evidence of scavenging, rather than active predation. Given the relative abundances of the MMQ carnivores, partnered with the size-estimates based on the striated bite marks, the feeding trace assemblage likely preserves the first evidence of cannibalism in Allosaurus.

Purpose: Isolated theropod teeth are abundant in the Upper Jurassic of the Lusitanian Basin and are an important source to reconstruct the diversity of this group as well as its geographic and stratigraphic distribution. However, reliably identification of isolated teeth is complex, especially for those morphotypes related to poorly represented groups. Herein a set of isolated theropod teeth collected in different sites from the Upper Jurassic of the Lusitanian Basin ranging from the late Kimmeridgian to late Tithonian in age are described and discussed. Methods: These teeth were grouped in seventeen distinct morphotypes based first on morphology and comparative anatomy. Multivariate statistical analyses were performed in order to assign each morphotype to a certain taxon. Results: The current analysis shows the presence of several groups of theropods such as Ceratosaurus, Torvosaurus, and Allosaurus beside morphotypes identified as belonging to indeterminate Megalosauroidea and Allosauroidea and morphotypes tentatively assigned to Tyrannosauroidea, Dromaeosauridae, and Richardoestesia. This faunal composition, namely the presence of a non-megalosaurid megalosauroid possibly related to the piatnitzkysaurid Marshosaurus, indicates a higher diversity of theropods in the Late Jurassic of the Lusitanian Basin than previously known, based on more complete specimens. Results obtained from this analysis partially agree with previous studies of other collections with isolated theropod teeth from the Upper Jurassic of Portugal such as those of the Guimarota coal mine. However, the presence of velociraptorine dromaeosaurids, compsognathids, and troodontids reported from this site could not be confirmed in the sample herein analyzed. This analysis also indicates a great similarity of the theropod faunas from the Late Jurassic of the Lusitanian Basin and other European chronocorrelative localities such as those from Spain and Germany. © 2017, Springer International Publishing AG.

A set of cranial and postcranial specimens, including two partial maxillae, several isolated teeth, vertebrae and appendicular elements of theropod dinosaurs is described. These specimens were collected in different Upper Jurassic sites from the Lusitanian Basin (Portugal) and show several characters that allow its identification as belonging to megalosauroid tetanurans. Some of these elements have a combination of features exclusively shared with other megalosaurids known in the Portuguese record, in particular with the recently described species Torvosaurus gurneyi from synchronic sedimentary levels. The geographic and stratigraphic distribution of the specimens of megalosauroids currently known in the Portuguese record indicates that members of this clade were relatively abundant from the upper Kimmeridgian to the lowermost Tithonian of the Lusitanian Basin, especially in the Consolacao Sub-basin. The analysis of the different specimens described allows testing hypotheses about the distribution and variability of some characters among the Portuguese forms related to Torvosaurus.

Isolated theropod teeth from the Tacuarembo Formation (Late Jurassic of Uruguay) are comprehensively described. Several features (mesial teeth with restricted mesial carina not twisted lingually, presence of lingual flutes, labially displaced distal carina, DC between 9 and 12.5) allow the assignment to the genus Ceratosaurus. This referral is supported by multivariate and phylogenetic analysis. Similarities with spinosaurid teeth are discussed, and the identification of Jurassic teeth from Niger and Tanzania as members of Spinosauridae is questioned, being referred herein to Ceratosauridae. Hence, the family was widespread in the Jurassic of Gondwana. The presence of Ceratosaurus is, along with recently identified Torvosaurus teeth, another evidence of the Late Jurassic age of the fossiliferous horizons of the Tacuarembo Formation.

Redescription of a trackway from the Salt Wash Member of the Morrison Formation (Upper Jurassic) in eastern Utah and comparisons with other tracks known from the Jurassic and Cretaceous of the region and the Late Jurassic globally indicate that the large theropod ichnogenus Hispanosauropus Mensink and Mertmann, 1984, previously known only from Europe, occurs also in the Morrison Formation. Hispanosauropus is distinct from Megalosauripus and most likely was made by an allosauroid theropod, although the possibility that it was made by a spinosauroid (torvosaurid) or a ceratosauroid cannot be ruled out. Close geographic and stratigraphic association of Hispanosauropus with the large theropod body fossil taxa Allosaurus, Torvosaurus, and Ceratosaurus in both North America and the Iberian Peninsula strengthens the case for the track's having been made by one of these genera. Megalosauripus appears to dominate large theropod track samples from the Entrada Sandstone through the base of the Morrison Formation (Ti...

A new specimen of the theropod dinosaur Torvosaurus tanneri discovered by Elmer Riggs in 1899 in the Freezeout Hills of Wyoming and held in the Field Museum of Natural History is described. This specimen demonstrates that unreported material of this species has been present in museum collections 80 years prior to the species' scientific description and it likely represents the first non-dental material of this species to be collected. This material comprises parts of the left foot and right hand, including phalanges which were previously unknown for Torvosaurus, and substantiates the possibility that other Torvosaurus material may be undiscovered in museum collections. Its occurrence in a multitaxon quarry is consistent with other skeletal finds of Torvosaurus, all or most of which occur in association with other, more common Morrison dinosaur taxa.

Fragmentary remains of a large, robustly built theropod dinosaur were recovered from the marine middle Callovian Ornatenton Formation of north-eastern Northrhine-Westphalia, Germany. The specimen includes a premaxilla, maxilla, lacrimal, postorbital, dentary, several caudal vertebrae, ribs, fibulae, astragalus, and partial calcaneum. It is here described as a new species of megalosauroid, Wiehenvenator albati n. gen. n. sp., diagnosed by a strongly reduced maxillary antorbital fossa on the base of the ascending process of the maxilla, a very short anterior ramus of the lacrimal with an additional pneumatic depression anteroventral to the lacrimal fenestra, a transversely expanded orbital facet in the postorbital, and a laterally flexed proximal end of the ascending process of the astragalus. Phylogenetic analysis recovers Wiehenvenator as a megalosaurine megalosaurid, sister taxon to the Late Jurassic genus Torvosaurus. It thus adds to the considerable diversity of megalosauroids in the Middle Jurassic. A time-calibrated phylogeny of theropods indicates a rapid radiation of averostran theropods between the Toarcian and the Bathonian. This radiation was probably triggered by the Pliensbachian-Toarcian extinction event, which might have been more important for theropod evolution than the Triassic-Jurassic extinction. The fossil record indicates a faunal turnover from megalosauroid dominated Middle Jurassic to allosauroid / coelurosaur dominated Late Jurassic faunas. However, differences in the Middle and Late Jurassic theropod fossil records both in respect to geographic distribution of localities, as well as sampled environments make this inference problematic, at least in respect to allosauroids. An analysis of environmental preferences of allosauroids and megalosauroids indicates that the former preferred inland environments, whereas the latter are more common in nearshore environments.

I report here on the discovery of the most complete megalosaurid skull known to date, from the Calcaire de Caen Formation of northwesten France. The specimen, which represents a new species is questionably referred to Poekilopleuron. It includes a nearly complete, unornamented skull, characterized by its low lateral profile. In addition to its historical significance, it provides additional characters that are crucial for reconstructing the phylogeny and biogeography of basal theropods. Poekilopleuron? valesdunensis new species is closely related to Eustreptospondylus and Afrovenator, and is united with Torvosaurus in the family of Megalosauridae. The Megalosauridae appear less derived than the Allosauroidea but resemble the Spinosauridae, with which they form the sister-group to the Neotetanurae. The proposed phylogenetic analysis hypothesizes two previously unrecognized major radiations of carnivorous dinosaurs.

The Lourinha Formation (Kimmeridgian-Tithonian) of Central West Portugal is well known for its diversified dinosaur fauna similar to that of the Morrison Formation of North America; both areas share dinosaur taxa including the top predator Torvosaurus, reported in Portugal. The material assigned to the Portuguese T. tanneri, consisting of a right maxilla and an incomplete caudal centrum, was briefly described in the literature and a thorough description of these bones is here given for the first time. A comparison with material referred to Torvosaurus tanneri allows us to highlight some important differences justifying the creation of a distinct Eastern species. Torvosaurus gurneyi n. sp. displays two autapomorphies among Megalosauroidea, a maxilla possessing fewer than eleven teeth and an interdental wall nearly coincidental with the lateral wall of the maxillary body. In addition, it differs from T. tanneri by a reduced number of maxillary teeth, the absence of interdental plates terminating ventrally by broad V-shaped points and falling short relative to the lateral maxillary wall, and the absence of a protuberant ridge on the anterior part of the medial shelf, posterior to the anteromedial process. T. gurneyi is the largest theropod from the Lourinha Formation of Portugal and the largest land predator discovered in Europe hitherto. This taxon supports the mechanism of vicariance that occurred in the Iberian Meseta during the Late Jurassic when the proto-Atlantic was already well formed. A fragment of maxilla from the Lourinha Formation referred to Torvosaurus sp. is ascribed to this new species, and several other bones, including a femur, a tibia and embryonic material all from the Kimmeridgian-Tithonian of Portugal, are tentatively assigned to T. gurneyi. A standard terminology and notation of the theropod maxilla is also proposed and a record of the Torvosaurus material from Portugal is given.

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. Jurassic Foundation financial support under the project: (Dinosaur Eggs and Embryos of the Lourinha˜ Formation [Upper Jurassic, Portugal]), DESY grants: (I-20110184 EC, I-20110229 EC projects), FCT/MCE grant: (PEst-OE/FIS/UI0275/2011), FCT scholarship: (SFRH/BD/62979/2009), European Science Foundation.

Remains of theropod dinosaurs are very rare in Northern Germany because the area was repeatedly submerged by a shallow epicontinental sea during the Mesozoic. Here, 80 Late Jurassic theropod teeth are described of which the majority were collected over decades from marine carbonates in nowadays abandoned and backfilled quarries of the 19th century. Eighteen different morphotypes (A-R) could be distinguished and 3D models based on micro-CT scans of the best examples of all morphotypes are included as supplements. The teeth were identified with the assistance of discriminant function analysis and cladistic analysis based on updated datamatrices. The results show that a large variety of theropod groups were present in the Late Jurassic of northern Germany. Identified specimens comprise basal Tyrannosauroidea, as well as Allosauroidea, Megalosauroidea cf. Marshosaurus, Megalosauridae cf. Torvosaurus and probably Ceratosauria. The formerly reported presence of Dromaeosauridae in the Late Jurassic of northern Germany could not be confirmed. Some teeth of this study resemble specimens described as pertaining to Carcharodontosauria (morphotype A) and Abelisauridae (morphotype K). This interpretation is however, not supported by discriminant function analysis and cladistic analysis. Two smaller morphotypes (N and Q) differ only in some probably size-related characteristics from larger morphotypes (B and C) and could well represent juveniles of adult specimens. The similarity of the northern German theropods with groups from contemporaneous localities suggests faunal exchange via land-connections in the Late Jurassic between Germany, Portugal and North America.

Body fossils of the Iberian Peninsula dinosaurs are very relevant for the knowledge of several aspects of the evolutionary history of the group, and, in addition, for the interpretation of the distribution of many of its components, due to the geographic situation of the Iberian Peninsula. Almost all of the groups of dinosaurs are represented in the Iberian Peninsula record: ornithopods, thyreophorans, theropods and sauropods. These groups are present, mainly, in the transit Jurassic-Cretaceous (Kimmeridigian- Berriasian), the upper part of the Lower Cretaceous (Barremian-Aptian) and in the end of the Upper Cretaceous (Campanian-Masstrichtian). Ornithischian dinosaurs are represented by thyreophorans such as the stegosaurians Dacentrurus and Stegosaurus, the ankylosaurs Dracopelta, Polacanthus and Struthiosaurus, and ornithopods like hypsilophodontids, basal iguanodontians (Rhabdodon), dryosaurids, camptosaurids (Draconyx and Camptosaurus), iguanodontids (Iguanodon) and hadrosaurids (Pararhabdodon). Some Incertae sedis and taxa in process of description are present too. Sauropods are represented by taxa related to Neosauropoda (Lourinhasaurus, Dinheirosaurus, Galveosaurus and Losillasaurus) and titanosauriforms (Aragosaurus, Lusotitan and Lirainosaurus). In addition, new forms are still in description, like the sauropods of Riodeva (Teruel), Penarroya de Tastavins (Teruel) and Morella (Castellon). Theropods are represented by the ceratosaurian Ceratosaurus, the spinosauroid Torvosaurus, the carnosaurs Lourinhanosaurus and Allosaurus, the tyrannosaurid Aviatyrannis, the ornithomimosaur Pelecanimimus, and the avian-theropods Iberomesornis, Concornis, Eoalulavis and Noguerornis. Nevertheless, theropods diversity is more abundant as it shows the great variability of teeth morphotypes identified.

Theropod dinosaurs form a highly diversified clade, and their teeth are some of the most common components of the Mesozoic dinosaur fossil record. This is the case in the Lourinha Formation (Late Jurassic, Kimmeridgian-Tithonian) of Portugal, where theropod teeth are particularly abundant and diverse. Four isolated theropod teeth are here described and identified based on morphometric and anatomical data. They are included in a cladistic analysis performed on a data matrix of 141 dentition-based characters coded in 60 taxa, as well as a supermatrix combining our dataset with six recent datamatrices based on the whole theropod skeleton. The consensus tree resulting from the dentition-based data matrix reveals that theropod teeth provide reliable data for identification at approximately family level. Therefore, phylogenetic methods will help identifying theropod teeth with more confidence in the future. Although dental characters do not reliably indicate relationships among higher clades of theropods, they demonstrate interesting patterns of homoplasy suggesting dietary convergence in (1) alvarezsauroids, therizinosaurs and troodontids; (2) coelophysoids and spinosaurids; (3) compsognathids and dromaeosaurids; and (4) ceratosaurids, allosauroids and megalosaurids. Based on morphometric and cladistic analyses, the biggest tooth from Lourinha is referred to a mesial crown of the megalosaurid Torvosaurus tanneri , due to the elliptical cross section of the crown base, the large size and elongation of the crown, medially positioned mesial and distal carinae, and the coarse denticles. The smallest tooth is identified as Richardoestesia , and as a close relative of R. gilmorei based on the weak constriction between crown and root, the “eight-shaped” outline of the base crown and, on the distal carina, the average of ten symmetrically rounded denticles per mm, as well as a subequal number of denticles basally and at mid-crown. Finally, the two medium-sized teeth belong to the same taxon and exhibit pronounced interdenticular sulci between distal denticles, hooked distal denticles for one of them, an irregular enamel texture, and a straight distal margin, a combination of features only observed in abelisaurids. They provide the first record of Abelisauridae in the Jurassic of Laurasia and one of the oldest records of this clade in the world, suggesting a possible radiation of Abelisauridae in Europe well before the Upper Cretaceous.