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New Ornithopod from the Cedar Mountain Formation (Lower Cre- taceous) of Eastern Utah

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The first occurrence of an iguanodontian from the Lower Cretaceous Poison Strip Member of the Cedar Mountain Formation, Utah, is described and named. This new taxon is represented by a well-preserved ilium, femora, tibiae, and vertebrae, as well as other material. The fe-mora are typical for an ornithopod, but the ilium has a short, horizontal postacetabular process that is functionally an antitrochanter.
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... However, the presence or absence of this sulcus is related to individual variation in Iguanodon bernissartensis and probably in Mantellisaurus atherfieldensis [27]. Furthermore, a longitudinal ventral sulcus has been reported in other styracosternans, such as Dakotadon lakotaensis, Hypselospinus fittoni or Planicoxa venenica [20,27,35,36]. ...
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Iguanodon bernissartensis is the most frequently and widely cited styracosternan ornithopod in Western Europe during the Early Cretaceous, although some of these assignments likely need to be revised to establish the true distribution of the taxon. Here, we describe a new specimen of I. bernissartensis from the upper Barremian of the Iberian Peninsula. Based on the unique combination of shared characters, the new specimen from the Arcillas de Morella Formation at Morella locality (Castellón, Spain) can be confidently referred to Iguanodon bernissartensis. These characters include parallel-sided anterior and posterior margins of the dorsal and the caudal neural spines as well as the presence of a ventral keel in the posterior dorsal centra and a broad ventral sulcus in the midline of the central surface of the most posterior sacral vertebrae. This new evidence of Iguanodon bernissartensis reinforces the knowledge about styracosternan ornithopods as the most frequently recorded dinosaur group in the Arcillas de Morella Formation.
... Two of these features-a dorsoventrally low ilium (not included in the dataset) and a triangular brevis shelf (character 331), present in Anabisetia saldiviai (see Coria and Calvo, 2002), Gasparinisaura cincosaltensis (MCS-3; Salgado et al., 1997;unpublished data, Herne, 2008), and Macrogryphosaurus gondwanicus (see Calvo et al., 2007)-were mentioned above. These features are also present in the four dryosaurids, Dryosaurus spp., Dysalotosaurus lettowvorbecki, Eousdryosaurus nanohallucis Escaso et al., 2014, andValdosaurus canaliculatus (Janensch, 1955;Galton, 1981;Escaso et al., 2014;Barrett, 2016), and also the iguanodontians Planicoxa venenica DiCroce and Carpenter, 2001 and Osmakasaurus depressus Gilmore, 1909 (Carpenter andWilson, 2008;McDonald, 2011) not included in this study. However, it is of note that the presence of a triangular brevis shelf (character 331) was not recovered as synapomorphic in any of the clades. ...
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The Flat Rocks locality in the Wonthaggi Formation (Strzelecki Group) of the Gippsland Basin, southeastern Australia, hosts fossils of a late Barremian vertebrate fauna that inhabited the ancient rift between Australia and Antarctica. Known from its dentary, Qantassaurus intrepidus Rich and Vickers-Rich, 1999 has been the only dinosaur named from this locality. However, the plethora of vertebrate fossils collected from Flat Rocks suggests that further dinosaurs await discovery. From this locality, we name a new small-bodied ornithopod, Galleonosaurus dorisae n. gen. n. sp. from craniodental remains. Five ornithopodan genera are now named from Victoria. Galleonosaurus dorisae n. gen. n. sp. is known from five maxillae, from which the first description of jaw growth in an Australian dinosaur is provided. The holotype of Galleonosaurus dorisae n. gen. n. sp. is the most complete dinosaur maxilla known from Victoria. Micro-CT imagery of the holotype reveals the complex internal anatomy of the neurovascular tract and antorbital fossa. We confirm that Q. intrepidus is uniquely characterized by a deep foreshortened dentary. Two dentaries originally referred to Q. intrepidus are reassigned to Q. ? intrepidus and a further maxilla is referred to cf. Atlascopcosaurus loadsi Rich and Rich, 1989. A further ornithopod dentary morphotype is identified, more elongate than those of Q. intrepidus and Q. ? intrepidus and with three more tooth positions. This dentary might pertain to Galleonosaurus dorisae n. gen. n. sp. Phylogenetic analysis recovered Cretaceous Victorian and Argentinian nonstyracosternan ornithopods within the exclusively Gondwanan clade Elasmaria. However, the large-bodied taxon Muttaburrasaurus langdoni Bartholomai and Molnar, 1981 is hypothesised as a basal iguanodontian with closer affinities to dryomorphans than to rhabdodontids. UUID: http://zoobank.org/4af87bb4-b687-42f3-9622-aa806a6b4116
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Full-text available
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