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Therizinosauroids are an enigmatic group of dinosaurs known mostly from the Cretaceous period of Asia, whose derived members are characterized by elongate necks, laterally expanded pelves, small, leaf-shaped teeth, edentulous rostra and mandibular symphyses that probably bore keratinized beaks1,2. Although more than a dozen therizinosauroid taxa are known, their relationships within Dinosauria have remained controversial because of fragmentary remains and an unusual suite of characters. The recently discovered ‘feathered’ therizinosauroid Beipiaosaurus from the Early Cretaceous of China helped to clarify the theropod affinities of the group3. However, Beipiaosaurus is also poorly represented. Here we describe a new, primitive therizinosauroid from an extensive paucispecific bonebed at the base of the Cedar Mountain Formation (Early Cretaceous) of east-central Utah4,5. This new taxon represents the most complete and most basal therizinosauroid yet discovered. Phylogenetic analysis of coelurosaurian theropods incorporating this taxon places it at the base of the clade Therizinosauroiden, indicating that this species documents the earliest known stage in the poorly understood transition from carnivory to herbivory within Therizinosauroidea. The taxon provides the first documentation, to our knowledge, of therizinosauroids in North America during the Early Cretaceous.
Acta Geologica Sinica, 2007
We herein describe an associated partial postcranial skeleton of a theropod dinosaur discovered in the Lower Cretaceous Xinminpu Group of the Yujingzi Basin, in the Jiuquan area of Gansu Province, northwestern China. Features of its humerus, such as strongly expanded proximal and distal ends, a well developed medial tuberosity, distal condyles expressed on the humeral cranial surface, and a hypertrophied entepicondyle, definitively establish the therizinosauroid affinities of the specimen. It differs from other therizinosauroids in having a shallow, poorly demarcated glenoid fossa with a prominent rounded and striated tumescence on the dorsomedial surface of its scapular portion, and a pubis with a strongly concave cranial margin. It represents a new taxon, Suzhousaurus megatherioides gen. et sp. nov. Cladistic analysis recovers Suzhousaurus as the sister taxon of Nothronychus mckinleyi from the mid-Cretaceous of western North America; together, they are basal members of the Therizinosauroidea, more derived than the Early Cretaceous Falcarius and Beipiaosaurus but less derived than Alxasaurus and the Therizinosauridae. Along with “Nanshiungosaurus” bohlini from possibly coeval beds in the Mazongshan area of northern-most Gansu, Suzhousaurus represents one of the largest-known Early Cretaceous therizinosauroids, demonstrating that this clade attained considerable body size early in its evolutionary history.
At The Top of Grand Staircase: the Late Cretaceous of southern Utah, 2013
Recent interest in Upper Cretaceous formations of southern Utah including intense collection efforts by the Kaiparowits Basin Project – a joint collaboration between the Utah Museum of Natural History, the University of Utah, and the Bureau of Land Management – has added considerably to our understanding of dinosaur diversity in the Western Interior Basin. These taxonomically unique and historically underrepresented ecosystems document a relatively high diversity of theropods, including a minimum of seven taxa known from the Kaiparowits Formation alone. Recent discoveries include at least fi ve new taxa: Hagryphus giganteus, the fi rst diagnostic North American oviraptorosaurian south of Montana; a new species of troodontid paravian; Nothronychus graffami, the most complete therizinosaurid skeleton yet discovered; and two new tyrannosaurid taxa, including Teratophoneus curriei and an undescribed taxon that represents the oldest North American tyrannosaurid recovered to date. Presently, data-rich paleobiogeographical comparison of latitudinally arrayed, coeval Western Interior Basin formations can only be made for a short temporal window that includes the upper Campanian Kaiparowits Formation. These investigations reveal that theropod diversity is relatively homogenous at higher taxonomic levels. Yet new discoveries also demonstrate a high degree of interformational, species-level endemism, indicating that the southern Utah theropod fauna is surprisingly unique and that theropod ranges in the upper Campanian Western Interior Basin were more restricted than previously understood. On the basis of these data, we argue against the referral of fragmentary dinosaur remains and teeth recovered from upper Campanian strata of the Western Interior Basin to taxa from other Western Interior Basin formations without substantial morphological evidence.
PLoS ONE, 2010
Background: The theropod dinosaur family Troodontidae is known from the Upper Jurassic, Lower Cretaceous, and Upper Cretaceous of Asia and from the Upper Jurassic and Upper Cretaceous of North America. Before now no undisputed troodontids from North America have been reported from the Early Cretaceous. Methodology/Principal Findings: Herein we describe a theropod maxilla from the Lower Cretaceous Cedar Mountain Formation of Utah and perform a phylogenetic analysis to determine its phylogenetic position. The specimen is distinctive enough to assign to a new genus and species, Geminiraptor suarezarum. Phylogenetic analysis places G. suarezarum within Troodontidae in an unresolved polytomy with Mei, Byronosaurus, Sinornithoides, Sinusonasus, and Troodon + (Saurornithoides + Zanabazar). Geminiraptor suarezarum uniquely exhibits extreme pneumatic inflation of the maxilla internal to the antorbital fossa such that the anterior maxilla has a triangular cross-section. Unlike troodontids more closely related to Troodon, G. suarezarum exhibits bony septa between the dental alveoli and a promaxillary foramen that is visible in lateral view. Conclusions/Significance: This is the first report of a North American troodontid from the Lower Cretaceous. It therefore contributes to a fuller understanding of troodontid biogeography through time. It also adds to the known dinosaurian fauna of the Cedar Mountain Formation.
Background: The Yellow Cat Member of the Cedar Mountain Formation (Early Cretaceous, Barremian? – Aptian) of Utah has yielded a rich theropod fauna, including the coelurosaur Nedcolbertia justinhofmanni, the therizinosauroid Falcarius utahensis, the troodontid Geminiraptor suarezarum, and the dromaeosaurid Utahraptor ostrommaysorum. Recent excavation has uncovered three new dromaeosaurid specimens. One specimen, which we designate the holotype of the new genus and species Yurgovuchia doellingi, is represented by a partial axial skeleton and a partial left pubis. A second specimen consists of a right pubis and a possibly-associated radius. The third specimen consists of a tail skeleton that is unique among known Cedar Mountain dromaeosaurids. Methodology/Principal Findings: Y. doellingi resembles Utahraptor ostrommaysorum in that its caudal prezygapophyses are elongated but not to the degree present in most dromaeosaurids. The specimen represented by the right pubis exhibits a pronounced pubic tubercle, which is a velociraptorine trait that is absent in Y. doellingi. The specimen represented by the tail skeleton exhibits the extreme elongation of the caudal prezygapophyses that is typical of most dromaeosaurids. Here we perform a phylogenetic analysis to determine the phylogenetic position of Y. doellingi. Using the resulting phylogeny as a framework, we trace changes in character states of the tail across Coelurosauria to elucidate the evolution of the dromaeosaurid tail. Conclusions/Significance: The new specimens add to the known diversity of Dromaeosauridae and to known diversity within the Yellow Cat paleofauna. Their presence demonstrates that the lower Yellow Cat paleofauna included at least three small, predatory theropods (including two dromaeosaurid species), and the upper Yellow Cat paleofauna included at least two dromaeosaurid species. Phylogenetic analysis places Y. doellingi in a clade with Utahraptor, Achillobator, and Dromaeosaurus. Character state distribution indicates that the presence of intermediate-length caudal prezygapophyses in that clade is not an evolutionarily precursor to extreme prezygapophyseal elongation but represents a secondary shortening of caudal prezygapophyses. It appears to represent part of a trend within Dromaeosauridae that couples an increase in tail flexibility with increasing size.
2012
Background The Yellow Cat Member of the Cedar Mountain Formation (Early Cretaceous, Barremian?) of Utah has yielded a rich dinosaur fauna, including the basal therizinosauroid theropod Falcarius utahensis at its base. Recent excavation uncovered a new possible therizinosauroid taxon from a higher stratigraphic level in the Cedar Mountain Formation than F. utahensis.
PLoS ONE, 2013
Therizinosauria are an unusual group of theropod dinosaurs, found mostly in the Cretaceous deposits in Mongolia, China and western USA. The basal forms of this group are represented by incomplete or disarticulated material. Here, we report a nearly complete, articulated skeleton of a new basal therizinosaur from the Early Cretaceous Yixian Formation of Jianchang County, western part of Liaoning Province, which sheds light on our understanding of anatomy of basal therizinosaurs. This new dinosaur shows some typical therizinosaur features, such as neural spines of the anterior caudal vertebrae that possess anterior and posterior alae, a rectangular buttress on the ventrolateral side of the proximal end of metacarpal I, and appressed metatarsal shafts. Our phylogenetic analysis suggests that it is a basal therizinosaur (sister taxon to Therizinosauroidea) because it bears many basal therizinosaur characters in the dentition, pelvis and hind limbs. The new therizinosaur described here has unique tooth and jaw characters such as the offsetting of the tooth row by a shelf and dentary teeth with labially concave and lingually convex dentary teeth, similar to ornithopods and ceratopsians.
PLoS ONE, 2014
The oviraptorosaurian theropod dinosaur clade Caenagnathidae has long been enigmatic due to the incomplete nature of nearly all described fossils. Here we describe Anzu wyliei gen. et sp. nov., a new taxon of large-bodied caenagnathid based primarily on three well-preserved partial skeletons. The specimens were recovered from the uppermost Cretaceous (upper Maastrichtian) Hell Creek Formation of North and South Dakota, and are therefore among the stratigraphically youngest known oviraptorosaurian remains. Collectively, the fossils include elements from most regions of the skeleton, providing a wealth of information on the osteology and evolutionary relationships of Caenagnathidae. Phylogenetic analysis reaffirms caenagnathid monophyly, and indicates that Anzu is most closely related to Caenagnathus collinsi, a taxon that is definitively known only from a mandible from the Campanian Dinosaur Park Formation of Alberta. The problematic oviraptorosaurs Microvenator and Gigantoraptor are recovered as basal caenagnathids, as has previously been suggested. Anzu and other caenagnathids may have favored well-watered floodplain settings over channel margins, and were probably ecological generalists that fed upon vegetation, small animals, and perhaps eggs.
Books Event: (1) Three Lectures on Habad Hasidism, Jerusalem: Schocken Institute for Jewish Research, 2024; (2) Wrestling with the Esoteric: Three Lectures on Yehuda Leib Ashlag and 20th Century Kabbalah, Jerusalem: Schocken Institute for Jewish Research, 2024; (3) Three Lectures on Bratslav Hasidism, Jerusalem: Schocken Institute for Jewish Research, 2024
Il existe deux types de texte régissant les règles à prendre en compte dans le calcul des installations électriques :
Environmental Humanities 11 (1), 2019
This special section on toxic embodiment examines variously situated bodies, land- and waterscapes and their naturalcultural interactions with toxicity. With toxic pollutants as a rising threat, important questions about environmental justice, gender, and the sexual politics of environmental movements issue an urgent challenge to intersectional gender and science studies; to anticolonial, queer, and trans theory; as well as to environmental and human-animal studies at large. Taking up this challenge, this special section aims at attending to the ways toxic embodiment disturbs or aligns with multiple boundaries of sexes, generations, races, geographies, nation-states, and species and how toxicity has re-dynamized corporeality and the biochemical materiality of bodies. Citation Olga Cielemęcka, Cecilia Åsberg; Introduction: Toxic Embodiment and Feminist Environmental Humanities. Environmental Humanities 1 May 2019; 11 (1): 101–107. doi: https://doi.org/10.1215/22011919-7349433
En ningún lugar… Caraca y la romanización de la Hispania interior, 2019
Journal of Modern Italian Studies, 2024
University of Toronto Press & UCLA Center for 17th and 18th c. studies, 2020
Religion Compass, 2024
Science & Society 85:1, 2021
Journal of Asian Studies, 2022
Jurnal Pena Sains, 2017
Multiple Sclerosis Journal, 2008
International journal of engineering research and technology, 2021
Journal of Psychiatric Research, 2012
Anais do XXXVIII Encontro …, 2011
Cellular Microbiology, 2020
Heart, Lung and Circulation, 2016
EPRA International Journal of Economic and Business Review, 2020