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A new crested maniraptoran dinosaur from the Santana Formation (Lower Cretaceous) of Brazil
Abstract
The skull of a new, and highly unusual crested dinosaur with an elongate rostrum is the first dinosaur to be named from the Santana Formation of NE Brazil. Irritator challengeri gen. et sp. nov was most likely a maniraptoran dinosaur, but its affinities to other maniraptorans remain to be established. Unique features for Irritator include the pattern of tooth replacement, a highly reduced supratemporal fenestra, extreme lateral compression of the rostrum and a saggital crest comprised of the frontal and parietal bones. Irritator was most probably a piscivore. A land link between South America and the dinosaurian faunal province of North America and Asia is indicated, probably via Africa.
... The footprints are large, ranging from 28-40 cm in length and 20-30 cm in width (Carvalho et al. 1995). The probable trackmakers are large theropods related to the groups that are already known in the Cretaceous deposits of the basin, such as the Spinosauridae Angaturama limai or Irritator challengeri (Kellner and Campos 1996;Martill et al. 1996). However, the footprints from Milagres ichnosite are certainly older than the Aptian-Albian age of these fossils. ...
... Although the dinosaur footprints are still not recorded in the Aptian Romualdo Formation of the Araripe Basin, the unit contains five species of theropod dinosaurs (see Kellner and Campos 1996;Martill et al. 1996Martill et al. , 2000Kellner 1999;Aureliano et al. 2018;Sayão et al. 2020) and one possible Ornithischia (Leonardi and Borgomanero 1981), later considered as a theropod bone (Batista and Kellner 2007). The Romualdo Formation records the last marine ingression within the Cretaceous interior basins of Northeastern Brazil, with, at least, two distinct pulses of marine incursions associated with the formation of a proto-Atlantic Ocean (Assine et al. 2014;Custódio et al. 2017;Teixeira et al. 2017;Fürsich et al. 2019;Bom et al. 2021;Kroth et al. 2021). ...
Fossil footprints are generally recognized by morphological features from the feet registered on the unconsolidated substrate; therefore, they can also be understood as biogenic primary deformation structures. The footprints can be found in the bedding surface and as cross-section deformations of the strata. Then, the substrate properties and the animal’s behavior allow for a wide range of track morphologies. The main modes of footprint preservation can thus be evaluated as the relationship between the substrate and the lower surface of the feet. In the Araripe Basin, both kinds of preservation are found in the Mauriti, Rio da Batateira, Crato, and Exu formations. In the Mauriti Formation, the footprints are imprints in the bedding surface of fine to coarse-grained sandstones. The cross-section footprints occur in the Rio da Batateira, Crato, and Exu formations. These footprints are produced by foot pressure on a depositional surface, and transmitted downward inside a bed or a bed set. In some cases, they are difficult to recognize, as they can be misinterpreted as load or liquefaction inorganic features related to sediment compaction, usually triggered by earthquakes and not to trampling by terrestrial vertebrates. They are in reality load casts produced by dinosaur trampling, allowing evaluation of substrate consistency besides the potential trackmaker identification. The temporal and environmental contexts of the dinosaur footprints from the Araripe Basin include the dinosaur trampling in fluvial sand bars, floodplains, deltas, and saline-alkaline lake borders.
... For theropods, the record consists of the families Abelisauridae, Spinosauridae and Carcharodontosauridae. The Spinosauridae were excluded (de França et al., 2022;Martill et al., 1996;Sales et al., 2017). Although we still do not know whether spinosaurids were fully aquatic (Ibrahim et al., 2020) or partially adapted to life in water (Sereno et al., 2022), they in either case do not fit the distal alluvial plain setting of the Chacarilla Fm. ...
... Während viele Paläontologen sie am ehesten als Signalorgane im Sozialverhalten der Tiere interpretieren, wurde auch bereits darüber spekuliert, dass sie eventuell der Thermoregulation in einem warmen Klima gedient haben könnten (obwohl dies hauptsächlich in populärwissenschaftlichen Veröffentlichungen auftaucht, und nie im Detail untersucht wurde, ob und wie das funktionieren würde). Bailey (1997) (MaRtill et al. 1996;sues et al. 2002;schade et al. 2020 (Abb. 14). ...
... The footprints are large, ranging from 28-40 cm in length and 20-30 cm in width (Carvalho et al., 1995). Although the footprints from the Milagres ichnosite are certainly older than the Aptian/Albian age, the probable trackmakers are large theropods related to the groups that are already known in the Cretaceous deposits of the Araripe Basin, such as the Spinosauridae (Martill et al., 1996). There is also an isolated footprint, tridactyl and mesaxonic with rounded digit extremities and wide U-shaped hypexes. ...
A NEW DINOSAUR TRACKSITE FROM THE ARARIPE BASIN (BRAZIL) AND THE PUTATIVE EARLY PALEOZOIC AGE FOR THE MAURITI FORMATION
Pp 97-102 In: Louis H.Taylor, Robert G. Raynolds, and Spencer G. Lucas, eds., 2024, Vertebrate Paleoichnology: A Tribute to Martin Lockley. New Mexico Museum of Natural History and Science Bulletin.
Footprints in the Araripe Basin (Northeastern Brazil) are previously known in the Mauriti Formation only from the Milagres ichnosite (Milagres County, Ceará State) on coarse-to fine-grained sandstones. Since this lithostratigraphic unit is considered and mapped as Silurian-Devonian (despite the fact that no macro-or microfossils established its age) the presence of such footprints shows a temporal inconsistency. The dinosaur footprints found in a new ichnosite (Mauriti County, Ceará State) reinforce the Mesozoic age for the Mauriti Formation, and due to the proximity of the nearby Rio do Peixe basins and to the similarity of their dinosaur footprints, a particularly Early Cretaceous age is suggested. This new ichnosite, herein named as Mauriti ichnosite, presents seven isolated footprints. There are four tridactyl, mesaxonic isolated footprints with pointed (?theropod) and rounded digits (?ornithopod). The other imprints are rounded depressions with no clear digit impressions, surrounded by displacement rims or presenting fluidization features of indeterminate trackmakers. The partial sandstone filling of the footprints is similar to the surrounding matrix. They range from 30-48 cm in length and 25-48 cm in width. The paleoenvironmental interpretation of the dinoturbation strata is fluvial braided. The trackmakers are small and large bipeds, despite some pointed digits induce to consider them as theropods related to those already known in the Araripe Basin's Cretaceous formations. This new tracksite confirms the need to revise the age of the Mauriti Formation and the involved paleogeography, establishing a new stratigraphic framework for the lower successions of the Araripe Basin.
... The latter is Aptian/Albian in age (Barreto et al. 2022) and encompasses interbedded shales, marls, and limestones that have yielded plenty of calcareous concretions containing exceptionally well-preserved fossils (Konservat Lagerstätten) (Maisey 1991;Valença et al. 2003) that can bear its three-dimensionality and even soft tissue (Martill 1988;Maisey 1991;Kellner 1996Kellner , 1999, and from where pterosaurs are the most common tetrapods (Maisey 1991). Also abundant in this formation are fossil fishes (Maisey 1991;Fara et al. 2005), besides tetrapods other than pterosaurs such as theropod dinosaurs (Kellner 1996;Martill et al. 1996;Naish et al. 2004) crocodyliforms (Price 1959) and testudines (Price 1956;Hirayama 1998;Gaffney et al. 2001), as well as fossil plants and invertebrates (e.g. Coimbra et al. 2002;Lima et al. 2012) (Figure 1). ...
Pterosaurs, flying reptiles that lived during the Mesozoic era, were the first vertebrates to develop powered flight. Despite being patchy, the pterosaur fossil record extends worldwide, being quite diverse at the Araripe Basin, Brazil. The Romualdo Formation (Aptian-Albian), a Konservat Lagerstätten rich in calcareous concretions, has yielded several of these exceptionally well-preserved, three-dimensional fossils. MN 4727-V, the focus of the present study, consists exclusively of three-dimensionally preserved post-cranial axial and appendicular elements. The anatomy suggests that MN 4727-V is a pteranodontoid since it exhibits an enlarged, warped deltopectoral crest and a subtriangular distal articulation of the humerus. The phyloge-netic analysis recovered MN 4727-V as an anhanguerid by the combination of the following characters: scapula substantially shorter than the coracoid (sca/co < 0.80), and posterior expansion of the sternal articulation of the coracoid. The presence of elliptical-shaped, dorsomedially inclined depressions on the dorsal surface of the prezygapophyses of the preserved cervicals has never been reported for any other anhanguerid, although they might not be diagnostic to MN 4727-V. The tail bears unique middle caudals that exhibit ventral projections, a character previously reported only for Anhanguera piscator. The wingspan of MN 4727-V, a juvenile individual, was estimated to be about 3.9 metres.
... Prolific spinosaurine remains come from the Aptian record of the Araripe Basin (e.g. Kellner and Campos 1996;Martill et al. 1996;Sues et al. 2002;Bittencourt and Kellner 2004;Machado and Kellner 2007;Aureliano et al. 2018), from the Albian-Cenomanian São Luis-Grajaú Basin (Medeiros and Schultz 2002;Medeiros 2006;Kellner et al. 2011;França et al. 2022), and recently by a Spinosauridae tooth from the Albian-Cenomanian of the Potiguar Basin (Pereira et al. 2020). A dubious tooth was from the Cenomanian-Turonian of Argentina (Canudo et al. 2004), which potentially comprises the southernmost record of a spinosaurid in South America. ...
Supposed dinosaur remains were collected between 1859 and 1906 in the Lower Cretaceous Recôncavo Basin (Northeast Brazil). Since these materials remained undescribed, and most were considered lost. Recently, some of these historical specimens were rediscovered in the Natural History Museum of London, providing an opportunity to revisit them after 160 years. The specimens come from five different sites, corresponding to the Massacará (Berriasian-Barremian) and Ilhas (Valanginian-Barremian) groups. Identified bones comprise mainly isolated vertebral centra from ornithopods, sauropods, and theropods. Appendicular remains include a theropod pedal phalanx, humerus, and distal half of a left femur with elasmarian affinities. Despite their fragmentary nature, these specimens represent the earliest dinosaur bones discovered in South America, enhancing our understanding of the Cretaceous dinosaur faunas in Northeast Brazil. The dinosaur assemblage in the Recôncavo Basin resembles coeval units in Northeast Brazil, such as the Rio do Peixe Basin, where ornithopods coexist with sauropods and theropods. This study confirms the presence of ornithischian dinosaurs in Brazil based on osteological evidence, expanding their biogeographic and temporal range before the continental rifting between South America and Africa. Additionally, these findings reinforce the fossiliferous potential of Cretaceous deposits in Bahia State, which have been underexplored since their initial discoveries.
... Suppose two UNESCO states enter into negotiations regarding the return of a cultural object. In that case, both can submit the case to the Intergovernmental Committee for Promoting 22 Martill et al. 1996. 23 Cisneros et al. 2021. ...
While disputes concerning the return of antiquities and artworks have become increasingly prevalent and receive public attention, the parallel issue of returning unlawfully exported fossils is rarely discussed. The fossils of "Ubirajara jubatus" and Irritator challengeri are prime examples of such disputes: they were taken from Brazil unlawfully, as Brazilian researchers allege, and displayed in German museums. The return disputes were characterized by both parties relying on arguments based almost exclusively on public (international) law. This Article explores private law as an alternative approach to these and similar disputes, discussing whether the fossils are the property of Brazil and could, therefore, be claimed in an action for restitution under German law. It finds that both fossils belong to Brazil since the museums did not acquire good title through a good faith purchase or acquisitive prescription.
Tetrapod fossil footprints are common in the aeolian sandstones from the Botucatu Formation in many Brazilian states, all around the edge of the Paraná Basin. This unit is represented by well-selected, reddish aeolian sandstones, related to an extensive dune field. Its age is Early Cretaceous (Berriasian-Barremian). The main ichnosite from the Botucatu Formation occurs in the interior of São Paulo State, in the Araraquara region, at the São Bento quarry, where slabs for covering and paving of public sidewalks, were extracted. This quarry presents a section of a large dune, about 20 m high and 100 m long, exhibiting foresets with a dip of 29° in the S-SW direction. Alongside the bedding surfaces there are abundant tracks attributed to mammals, Theropoda and Ornithopoda. These are herein grouped in four morphotypes, in addition to other kinds of isolated footprints difficult to classify. All these occurrences belong to bipedal and functionally tridactyl dinosaurs; no Sauropodomorpha tracks were found. To these theropod and ornithopod footprints and trackways from the eastern side of the Paraná Basin are added those of the western side, in the area of Nioaque, Mato Grosso do Sul State. The Botucatu paleodesert harbored a possibly endemic fauna, of bipedal carnivorous and herbivorous dinosaurs, which makes difficult a faunistic comparison with other localities, in other paleobiogeographic contexts.
A new member of Spinosauridae from the Enciso Group (uppermost Barremian–lower Aptian) from Igea (La Rioja, Spain) is here erected on the
basis of axial, pelvic girdle, and hindlimb elements that exhibit a unique combination of characters. Riojavenatrix lacustris gen. et sp. nov. is one of
the latest Iberian and European spinosaurid taxa. It retains a triangular pubic boot, like the megalosaurids, and a medial condyle of the femur that
shows a transitional stage between the anteroposteriorly oriented long axis of non-spinosaurid theropods and the posteromedially oriented long
axis of Spinosauridae. The spinosaurid record of Iberia ranges from the late Hauterivian–early Barremian to the latest Barremian–early Aptian
so far, and both the oldest and the most recent evidence comes from the Cameros Basin, where spinosaurid remains are especially abundant in
the Barremian deposits. A review of the spinosaurid record has allowed us to dismiss the presence of the genus Baryonyx from Iberia; hence, only
Camarillasaurus, Iberospinus, Protathlitis, Riojavenatrix gen. nov., and Vallibonavenatrix are considered to be present in the Early Cretaceous of
Iberia. According to this study, Riojavenatrix is one of the youngest baryonychines in the fossil record.
Tyrannosaurids are a well-supported clade of very large predatory dinosaurs of Late Cretaceous Asiamerica. Traditional dinosaurian systematics place these animals within the infraorder Carnosauria with the other large theropods (allosaurids, megalosaurids). A new cladistic analysis indicates that the tyrannosaurs were in fact derived members of the Coelurosauria, a group of otherwise small theropods. Despite certain gross cranial similarities with the large predators of the Jurassic and Early Cretaceous, the Late Cretaceous tyrannosaurids are shown to be the sister group to ornithomimids and troodontids, which share a derived condition of the metatarsus. This clade is found to be nested within Maniraptora, which is a more inclusive taxon than previously recognized. The atrophied carpal structure found in tyrannosaurids and ornithomimids is derived from a maniraptoran condition with a large semilunate carpal, rather than from the plesiomorphic theropod morphology.
The taxa “Carnosauria” and “Deinonychosauria” (Dromaeosauridae plus Troodontidae) are shown to be polyphyletic, and the Late Jurassic African form Elaphrosaurus is found to be the sister taxon to Abelisauridae rather than a primitive ornithomimosaur. Purported allosaurid-tyrannosaurid synapomorphies are seen to be largely size-related, present in the larger members of both clades, but absent in smaller members of the Tyrannosauridae. The remaining giant tetanurine theropods (Megalosaurus and Torvosaurus) were found to be progressively distant outgroups to an allosaurid-coelurosaur clade. The inclusion of the Tyrannosauridae within Maniraptora suggests a major adaptive radiation of coelurosaurs within Cretaceous Asiamerica comparable to contemporaneous radiations in various herbivorous dinosaurian clades.
The theropod families Abelisauridae and Noasauridae appear closely related because of shared derived characters such as the short anterior area of the maxilla, the small or absent preantorbital fenestra, the quadrate fused to the quadratojugal, and cervical vertebrae with vestigial neural spines and hypertrophied epipophyses. The families appear linked to Ceratosauridae and are interpreted as Ceratosauria. They are very different from the clade Allosauridae‐Tyrannosauridae as well as from other Laurasian theropods.The geographic distribution of the Abelisauridae possibly includes Africa, India, South America and southern Europe, and they are generally associated with titanosaurid sauropods. It is considered that they are endemic to Gondwana, and the presence of abelisaurids in Europe may be the result of a migratory event from Africa.It is suggested that the Baharija theropods may be more related to the abelisaurs than to the tyrannosaurs.
A major question in Mesozoic biogeography is how the land-based dinosaurian radiation responded to fragmentation of Pangaea. A rich fossil record has been uncovered on northern continents that spans the Cretaceous, when continental isolation reached its peak. In contrast, dinosaur remains on southern continents are scarce. The discovery of dinosaurian skeletons from Lower Cretaceous beds in the southern Sahara shows that several lineages of tetanuran theropods and broad-toothed sauropods had a cosmopolitan distribution across Pangaea before the onset of continental fragmentation. The distinct dinosaurian faunas of Africa, South America, and Asiamerica arose during the Cretaceous by differential survival of once widespread lineages on land masses that were becoming increasingly isolated from one another.