Preliminary studies of a new dinosaur track locality from the Candeleros Formation (Cenomanian, Upper Cretaceous), Neuquén Basin, Argentina

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On dicraeosaurid (sauropoda) vertebra from the la amarga formation (barremian–aptian, lower cretaceous), Neuquén basin, patagonia, Argentina

Field works carried out by Dr. Bonaparte and collaborators in the La Amarga Formation (Barremian–Aptian) in 2000, allowed the collecting of a vertebral element not previously communicated. This material has not been properly protected, so it is broken and kept in paleontological collection of Museo Provincial “Olsacher” of Zapala city. The descriptions were based solely on a photograph. The parapophyses are located on the dorsal part of the centrum, like in the anterior dorsal vertebrae of Dicraeosaurus hansemanni Janensch and Amargasaurus cazaui Salgado and Bonaparte. The posterior articular surface of the centrum is strongly concave with an elliptical outline. The neural arch bears two deep and wide centropostzygapophyseal fossae with a triangular outline. These fossae are framed laterally by stout centropostzygapophyseal laminae, project dorsoventrally like a massive columnar bone. The transverse processes are inclined dorsally more than 30° from the horizontal axis, as in the dorsal vertebrae of D. hansemanni, A. cazaui, Brachytrachelopan mesai Rauhut, Remes, Fechner, Cladera and Puerta and Pilmatueia faundezi Coria, Windholz, Ortega and Currie. The element bears an elongate bifid neural spine, character that share with the most of presacral vertebrae of the dicraeosaurids. This structure is straight, dorsoanteriorly oriented and its degree of development reminds to the presacral vertebrae of A. cazaui. This element is similar to the anterior dorsal vertebrae of A. cazaui, although it could be comparable with Amargatitanis macni Apesteguía, come from the same locality and lithostratigraphic unit, whose presacral vertebrae are unknown.Fil: Windholz, Guillermo Jose. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigación en Paleobiología y Geología; Argentina. Provincia del Neuquén. Municipalidad de Plaza Huincul. Museo "Carmen Funes"; ArgentinaFil: Baiano, Mattia Antonio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigación en Paleobiología y Geología; Argentina. Provincia del Neuquén. Municipalidad de Plaza Huincul. Museo "Carmen Funes"; ArgentinaFil: Bellardini, Flavio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigación en Paleobiología y Geología; Argentina. Gobierno de la Provincia de la Pampa. Secretaria de Cultura. Direccion Provincial de Patrimonio Cultural.; ArgentinaFil: Meso, Jorge Gustavo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigación en Paleobiología y Geología; ArgentinaFil: Juáres Valieri, R.. Gobierno de la Provincia de Río Negro. Ministerio de Turismo, Cultura y Deporte. Secretaría de Cultura; Argentina. Museo de Ciencias de Añelo; ArgentinaFil: Porfiri, J.. Museo de Ciencias de Añelo; Argentina. Universidad Nacional del Comahue; ArgentinaFil: Filippi, L.. Gobierno de la Provincia del Neuquén. Municipalidad de Rincón de Los Sauces. Secretaria de Turismo y Patrimonio. Museo Municipal Argentino Urquiza; ArgentinaFil: Garrido, A.. Provincia de Neuquén. Ministerio de Energía, Ambiente y Servicios Públicos. Dirección Provincial de Minería. Museo Provincial de Ciencias Naturales Prof. "Dr. Juan A. Olsacher"; Argentina. Universidad Nacional del Comahue. Facultad de Ingeniería. Departamento de Geología y Petróleo; Argentina2das Jornadas de Paleovertebrados de la Cuenca NeuquinaNeuquénArgentinaAsociación Paleontológica Argentin

A new sphenodontian (Reptilia, Lepidosauria) from the Lower Cretaceous of Southern Italy and the phylogenetic affinities of the Pietraroia Plattenkalk rhynchocephalians

The Pietraroia Plattenkalk (Albian, Lower Cretaceous) of Southern Italy is known for well-preserved fossil vertebrates, including the rhynchocephalian lepidosaur Derasmosaurus pietraroiae. A previously described Pietraroian rhynchocephalian differs from Derasmosaurus in vertebral, pelvic and foot morphology. A third Pietraroian rhynchocephalian is described for the first time. The new specimen is smaller and more gracile than the other Pietraroian rhynchocephalians, shows a broad unpaired parietal with a small foramen, and robust dorsal neural spines. Comparison with the ontogenetic series of Sphenodon suggests that small body size and relatively broad parietal in the new rhynchocephalian indicate immaturity, although the complete obliteration of the interparietal suture and the relatively small size of the parietal foramen may support an ontogenetically mature condition for that specimen. The morphology of the dorsal vertebrae excludes referral to Derasmosaurus. Phylogenetic analyses placed the second specimen among the basal branch of Opisthodontia, and the third specimen and Derasmosaurus among Sphenodontinae. The phylogenetic reconstruction supports the interpretation of the Pietraroian rhynchocephalians as late-surviving members of Jurassic lineages

New information on paleopathologies in non-avian theropod dinosaurs: a case study on South American abelisaurids

Abstract Studies on pathological fossil bones have allowed improving the knowledge of physiology and ecology, and consequently the life history of extinct organisms. Among extinct vertebrates, non-avian dinosaurs have drawn attention in terms of pathological evidence, since a wide array of fossilized lesions and diseases were noticed in these ancient organisms. Here, we evaluate the pathological conditions observed in individuals of different brachyrostran (Theropoda, Abelisauridae) taxa, including Aucasaurus garridoi, Elemgasem nubilus, and Quilmesaurus curriei. For this, we use multiple methodological approaches such as histology and computed tomography, in addition to the macroscopic evaluation. The holotype of Aucasaurus shows several pathognomonic traits of a failure of the vertebral segmentation during development, causing the presence of two fused caudal vertebrae. The occurrence of this condition in Aucasaurus is the first case to be documented so far in non-tetanuran theropods. Regarding the holotype of Elemgasem, the histology of two fused vertebrae shows an intervertebral space between the centra, thus the fusion is limited to the distal rim of the articular surfaces. This pathology is here considered as spondyloarthropathy, the first evidence for a non-tetanuran theropod. The microstructural arrangement of the right tibia of Quilmesaurus shows a marked variation in a portion of the outer cortex, probably due to the presence of the radial fibrolamellar bone tissue. Although similar bone tissue is present in other extinct vertebrates and the cause of its formation is still debated, it could be a response to some kind of pathology. Among non-avian theropods, traumatic injuries are better represented than other maladies (e.g., infection, congenital or metabolic diseases, etc.). These pathologies are recovered mainly among large-sized theropods such as Abelisauridae, Allosauridae, Carcharodontosauridae, and Tyrannosauridae, and distributed principally among axial elements. Statistical tests on the distribution of injuries in these theropod clades show a strong association between taxa-pathologies, body regions-pathologies, and taxa-body regions, suggesting different life styles and behaviours may underlie the frequency of different injuries among theropod taxa

Diuqin lechiguanae gen. et sp. nov., a new unenlagiine (Theropoda: Paraves) from the Bajo de la Carpa Formation (Neuquén Group, Upper Cretaceous) of Neuquén Province, Patagonia, Argentina

Abstract Background Unenlagiine paravians are among the most relevant Gondwanan theropod dinosaur clades for understanding the origin of birds, yet their fossil record remains incomplete, with most taxa being represented by fragmentary material and/or separated by lengthy temporal gaps, frustrating attempts to characterize unenlagiine evolution. Results and conclusions Here we describe Diuqin lechiguanae gen. et sp. nov., a new unenlagiine taxon from the Upper Cretaceous (Santonian) Bajo de la Carpa Formation of the Neuquén Basin of Neuquén Province in northern Patagonia, Argentina that fills a substantial stratigraphic gap in the fossil record of these theropods. Although known only from a very incomplete postcranial skeleton, the preserved bones of Diuqin differ from corresponding elements in other unenlagiines, justifying the erection of the new taxon. Moreover, in several morphological aspects, the humerus of Diuqin appears intermediate between those of geologically older unenlagiines from the Neuquén Basin (e.g., Unenlagia spp. from the Turonian–Coniacian Portezuelo Formation) and that of the stratigraphically younger, larger-bodied Austroraptor cabazai from the Campanian–Maastrichtian Allen Formation. Consequently, the morphology of the new taxon appears to indicate a transitional stage in unenlagiine evolution. Phylogenetic analysis recovers Diuqin as a paravian with multiple plausible systematic positions, but the strongest affinity is with Unenlagiinae. The humerus of the new form exhibits subcircular punctures near its distal end that are interpreted as feeding traces most likely left by a conical-toothed crocodyliform, mammal, or theropod, the latter potentially corresponding to a megaraptorid or another unenlagiine individual. Thus, in addition to filling important morphological and temporal gaps in unenlagiine evolutionary history, the new taxon also offers information relating to the paleoecology of these theropods

A detailed osteological description of Xenotarsosaurus bonapartei (Theropoda: Abelisauridae): implications for abelisauroid phylogeny

Xenotarsosaurus bonapartei was the third abelisaurid theropod dinosaur to be named from Argentina. The holotype comprises two partial anterior dorsal vertebrae and a nearly complete right hind limb from the Upper Cretaceous (lower Cenomanian–upper Turonian) Bajo Barreal Formation, central Patagonia, Argentina. The materials display morphological features that undoubtedly position Xenotarsosaurus within Abelisauroidea. Moreover, detailed comparisons with members of that theropod group confirm the close relationship of this taxon to abelisaurids. Here we provide an emended diagnosis of Xenotarsosaurus bonapartei that includes five newly recognized autapomorphies: (1) anterior dorsal vertebrae with large, strongly dorsoventrally developed parapophyses; (2) anterior dorsal vertebrae with well-developed centroprezygapophyseal fossae that are taller dorsoventrally than wide mediolaterally; (3) fibular condyle of femur triangular in shape and projecting posteriorly; (4) well-marked groove on anterolateral corner of proximal fibula; and (5) iliofibularis tubercle of fibula distally interrupted by hook-like concavity. To determine its systematic position within Abelisauroidea, we incorporated Xenotarsosaurus into a phylogenetic analysis, recovering this theropod as a non-carnotaurine abelisaurid more derived than Eoabelisaurus mefi. Xenotarsosaurus displays several plesiomorphic traits when compared with penecontemporaneous abelisaurids from the Neuquén Group. Similarly, other non-avian dinosaur taxa from the Bajo Barreal Formation are frequently postulated as more phylogenetically basal than coeval forms from northern Patagonia. This scenario suggests the potential existence of provincialism in early Late Cretaceous continental vertebrate faunas of southern South America. The present study increases knowledge of abelisaurid systematics, evolution, and paleobiogeography and augments our understanding of the Upper Cretaceous dinosaur assemblage of central Patagonia.Fil: Ibiricu, Lucio Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto Patagónico de Geología y Paleontología; Argentina. Universidad Nacional de la Patagonia "San Juan Bosco"; ArgentinaFil: Baiano, Mattia Antonio. Provincia del Neuquén. Municipalidad de Plaza Huincul. Museo "Carmen Funes"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigación en Paleobiología y Geología; ArgentinaFil: Martínez, Rubén D.. Universidad Nacional de la Patagonia "San Juan Bosco"; ArgentinaFil: Alvarez, Bruno Nicolás. Universidad Nacional de la Patagonia Austral. Centro de Investigaciones y Transferencia Golfo San Jorge. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones y Transferencia Golfo San Jorge. Universidad Nacional de la Patagonia "San Juan Bosco". Centro de Investigaciones y Transferencia Golfo San Jorge; ArgentinaFil: Lamanna, Matthew C.. Carnegie Museum Of Natural History; Estados UnidosFil: Casal, Gabriel A.. Universidad Nacional de la Patagonia "San Juan Bosco"; Argentin

Appendicular osteology of <i>Skorpiovenator bustingorryi</i> (Theropoda, Abelisauridae) with comments on phylogenetic features of abelisaurids

Skorpiovenator bustingorryi is a derived abelisaurid theropod represented by a fairly complete skeleton from the Late Cretaceous sedimentary beds of north-western Patagonia. Although some features were described in the original paper, mainly related to the skull, the appendicular anatomy remains undescribed. The aim of the present contribution is to provide a detailed description and analysis of the available appendicular bones, including comparisons with other ceratosaurian theropods close to Skorpiovenator. In this way, new autapomorphies emerged to further distinguish Skorpiovenator from its relatives. Furthermore, a comprehensive phylogenetic analysis was performed and several characteristics of the hind limb, in particular some of the autopodium, resulted in the identification of new apomorphic traits for Ceratosauria and Abelisauridae. These features might prove to be useful for future phylogenetic analyses and may help to resolve the still confusing and debated internal relationships of abelisaurid theropods.</p

N-3 fatty acids in patients with multiple cardiovascular risk factors

BACKGROUND: Trials have shown a beneficial effect of n-3 polyunsaturated fatty acids in patients with a previous myocardial infarction or heart failure. We evaluated the potential benefit of such therapy in patients with multiple cardiovascular risk factors or atherosclerotic vascular disease who had not had a myocardial infarction. METHODS: In this double-blind, placebo-controlled clinical trial, we enrolled a cohort of patients who were followed by a network of 860 general practitioners in Italy. Eligible patients were men and women with multiple cardiovascular risk factors or atherosclerotic vascular disease but not myocardial infarction. Patients were randomly assigned to n-3 fatty acids (1 g daily) or placebo (olive oil). The initially specified primary end point was the cumulative rate of death, nonfatal myocardial infarction, and nonfatal stroke. At 1 year, after the event rate was found to be lower than anticipated, the primary end point was revised as time to death from cardiovascular causes or admission to the hospital for cardiovascular causes. RESULTS: Of the 12,513 patients enrolled, 6244 were randomly assigned to n-3 fatty acids and 6269 to placebo. With a median of 5 years of follow-up, the primary end point occurred in 1478 of 12,505 patients included in the analysis (11.8%), of whom 733 of 6239 (11.7%) had received n-3 fatty acids and 745 of 6266 (11.9%) had received placebo (adjusted hazard ratio with n-3 fatty acids, 0.97; 95% confidence interval, 0.88 to 1.08; P=0.58). The same null results were observed for all the secondary end points. CONCLUSIONS: In a large general-practice cohort of patients with multiple cardiovascular risk factors, daily treatment with n-3 fatty acids did not reduce cardiovascular mortality and morbidity. Copyright © 2013 Massachusetts Medical Society