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Unenlagiinia
Unenlagiidae is a proposed family of eumaniraptoran paravians that includes the subfamilies Unenlagiinae and possibly Halszkaraptorinae. Fossils of both subfamilies have been found in both Gondwanan and Laurasian deposits. The biology of the group suggests that some members were semiaquatic specialists. Classification The family Unenlagiidae traditionally includes the same members as the previously named subfamily of Dromaeosauridae, Unenlagiinae, so Unenlagiidae was often seen as a synonym of Dromaeosauridae. However, since the 2010s, there have been subsequent studies that have questioned this placement, necessitating the revival of the family name. Some have placed unenlagiids as outside Dromaeosauridae, being the sister taxon or closely related to Avialae, while others have placed the newly recognized halszkaraptorines in the family, as basal deinonychosaurs outside Dromaeosauridae and Troodontidae Troodontidae is a clade of bird-like theropod dinosaurs. During most o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Late Cretaceous
The Late Cretaceous (100.5–66 Ma) is the younger of two epochs into which the Cretaceous Period is divided in the geologic time scale. Rock strata from this epoch form the Upper Cretaceous Series. The Cretaceous is named after ''creta'', the Latin word for the white limestone known as chalk. The chalk of northern France and the white cliffs of south-eastern England date from the Cretaceous Period. Climate During the Late Cretaceous, the climate was warmer than present, although throughout the period a cooling trend is evident. The tropics became restricted to equatorial regions and northern latitudes experienced markedly more seasonal climatic conditions. Geography Due to plate tectonics, the Americas were gradually moving westward, causing the Atlantic Ocean to expand. The Western Interior Seaway divided North America into eastern and western halves; Appalachia and Laramidia. India maintained a northward course towards Asia. In the Southern Hemisphere, Australia and Ant ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Buitreraptor
''Buitreraptor'' (meaning "La Buitrera seizer") is a genus of dromaeosaurid dinosaurs that lived during the Late Cretaceous of Argentina at the Candeleros Formation. ''Buitreraptor'' was described in 2005 and the type species is ''Buitreraptor gonzalezorum''. It was rooster-sized and had a very elongated head with many small teeth. History of discovery Four specimens of ''Buitreraptor'' were found in 2004 in sandstone in Patagonia, Argentina during an excavation led by Sebastián Apesteguia, researcher of CONICET at the Fundacion Felix de Azara - Maimonides University, and Peter Makovicky, curator of dinosaurs at the Field Museum in Chicago. ''Buitreraptor'' is from the early Late Cretaceous Candeleros Formation, dating to the Cenomanian-Turonian ages approximately 98 to 97 million years ago, when South America was an isolated continent like Australia today. It was uncovered in a famous fossil site named ''La Buitrera'', the "vulture roost". Although dinosaurs are rare in thi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pygostylia
Pygostylia is a group of avialans which includes the Confuciusornithidae and all of the more advanced species, the Ornithothoraces. Definition The group Pygostylia was intended to encompass all avialans with a short, stubby tail, as opposed to the longer, unfused tails of more primitive species like ''Archaeopteryx lithographica''. It was named by Sankar Chatterjee in 1997.Chatterjee, S. 1997. ''The Rise of Birds.'' Baltimore: Johns Hopkins University Press. 312 pp. Luis Chiappe later defined Pygostylia as a node-based clade, "the common ancestor of the Confuciusornithidae and Neornithes plus all its descendants". In 2001, Jacques Gauthier and Kevin de Queiroz recommended that Chatterjee's original apomorphy-based clade concept be used instead of Chiappe's node-based definition,Gauthier, J., & De Queiroz, K. (2001). Feathered dinosaurs, flying dinosaurs, crown dinosaurs, and the name" Aves. ''New perspectives on the origin and early evolution of birds'', 7-41. but this recommendat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jeholornis
''Jeholornis'' (meaning "Jehol bird") is a genus of avialans that lived between approximately 122 and 120 million years ago during the early Cretaceous Period in China. Fossil ''Jeholornis'' were first discovered in the Jiufotang Formation in Hebei Province, China (in what was previously Rehe Province, also known as Jehol—hence the name) and additional specimens have been found in the older Yixian Formation. ''Jeholornis'' had long tails and few small teeth, and were approximately the size of turkeys,Holtz, Thomas R. Jr. (2008) ''Dinosaurs: The Most Complete, Up-to-Date Encyclopedia for Dinosaur Lovers of All Ages'Supplementary Information/ref> making them among the largest avialans known until the Late Cretaceous. Their diet included seeds of cycads, ''Ginkgo'' or similar plants. Description ''Jeholornis'' were relatively large, basal avialans, with a maximum adult length of up to 75 cm (2.5 ft) and an estimated weight of 2.27-9.1 kg (5-20 lbs). Another ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anchiornis
''Anchiornis'' is a genus of small, four-winged Paraves, paravian dinosaurs, with only one known species, the type species ''Anchiornis huxleyi'', named for its similarity to modern birds. The Latin name ''Anchiornis'' derives from a Greek word meaning "near bird", and ''huxleyi'' refers to Thomas Henry Huxley, a contemporary of Charles Darwin. ''Anchiornis'' fossils have been found only in the Tiaojishan Formation of Liaoning Province, Liaoning, China, in rocks dated to the Late Jurassic, about 160 million years ago. It is known from hundreds of specimens, and given the exquisite preservation of some of these fossils, it became the first Mesozoic dinosaur species for which almost the entire life appearance could be determined, and an important source of information on the early evolution of birds. Description ''Anchiornis huxleyi'' was a small, Bipedalism, bipedal Theropoda, theropod dinosaur with a triangular skull bearing several details in common with Dromaeosauridae, drom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Xiaotingia
''Xiaotingia'' is a genus of anchiornithid theropod dinosaur from Middle Jurassic or early Late Jurassic deposits of western Liaoning, China, containing a single species, ''Xiaotingia zhengi''. Discovery ''Xiaotingia'' is known from the holotype STM 27-2, an articulated and almost complete skeleton including the skull. It was probably collected in the Linglongta area, Jianchang, from the Tiaojishan Formation. Etymology ''Xiaotingia'' was first named by Xu Xing, You Hailu, Du Kai and Han Fenglu in 2011 and the type species is ''Xiaotingia zhengi''. The generic name and specific name together honour paleontologist Zheng Xiaoting. Description ''Xiaotingia'' lived around 155 million years ago which preceded ''Archaeopteryx'' that lived around 144 million years ago. ''Xiaotingia'' was morphologically similar to ''Archaeopteryx'' and was the size of a hen. It was about 60 cm long and weighed an estimated 0.82 kg. It was a small feathered dinosaur that lived in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anchiornithidae
Anchiornithidae ("near birds") is a family of eumaniraptorans which could be the basalmost family of birds (in the general sense) in the clade Avialae. Anchiornithids have been classified at varying positions in the maniraptoran tree, with some scientists classifying them as a distinct family, a basal subfamily of Troodontidae, members of Archaeopterygidae, or an assemblage of dinosaurs that are an evolutionary grade within Avialae or Paraves. Description Anchiornithids share many general features with other Paraves and early avialans. They were small and lightly-built feathered carnivores, similar in biology to ''Archaeopteryx'', early dromaeosaurids like ''Microraptor'', and particularly troodontids. They are almost exclusively known from Late Jurassic Chinese deposits, although ''Ostromia'' was discovered in Germany and ''Yixianosaurus'' (a putative member of the group only known from forelimbs) is believed to hail from the early Cretaceous. Most had long legs, arms, and ha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Archaeopteryx
''Archaeopteryx'' (; ), sometimes referred to by its German name, "" ( ''Primeval Bird''), is a genus of bird-like dinosaurs. The name derives from the ancient Greek (''archaīos''), meaning "ancient", and (''ptéryx''), meaning "feather" or "wing". Between the late 19th century and the early 21st century, ''Archaeopteryx'' was generally accepted by palaeontologists and popular reference books as the oldest known bird (member of the group Avialae). Older potential avialans have since been identified, including ''Anchiornis'', ''Xiaotingia'', and ''Aurornis''. ''Archaeopteryx'' lived in the Late Jurassic around 150 million years ago, in what is now southern Germany, during a time when Europe was an archipelago of islands in a shallow warm tropical sea, much closer to the equator than it is now. Similar in size to a Eurasian magpie, with the largest individuals possibly attaining the size of a raven, the largest species of ''Archaeopteryx'' could grow to about in len ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wellnhoferia
''Wellnhoferia'' (named after Peter Wellnhofer) is a genus of early prehistoric bird-like theropod dinosaur closely related to ''Archaeopteryx''. It lived in what is now Germany, during the Late Jurassic. While ''Wellnhoferia'' was similar to ''Archaeopteryx'', it had a shorter tail and its fourth toe was shorter than in ''Archaeopteryx''. Andrzej Elżanowski (2001) of the Institute of Zoology of the University of Wrocław, Poland, determined the differences resulted from a "phylogenetic reduction rather than individual variation." The type specimen is the Solnhofen Specimen of ''Archaeopteryx'' (BSP 1999). Discovered in the 1960s near Eichstätt, Germany and described in 1988 by Wellnhofer (as a specimen of ''Archaeopteryx''), it is currently located at the Bürgermeister-Müller-Museum in Solnhofen. It was originally classified as a ''Compsognathus ''Compsognathus'' (; Greek ''kompsos''/κομψός; "elegant", "refined" or "dainty", and ''gnathos''/γνάθος; "jaw") i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alcmonavis
''Alcmonavis'' is a basal genus of avialan dinosaur that during the Late Jurassic lived in the area of present Germany. The only named species in the genus is ''Alcmonavis poeschli''. Its only known fossil was originally reported as a specimen of ''Archaeopteryx''. Discovery and naming Amateur paleontologist Roland Pöschl systematically excavates the Alte Schöpfel quarry on the Schaudiberg, at Mühlheim near Mörnsheim in Bavaria. In November 2017, he discovered a slab showing a right wing of a primordial bird. The piece was prepared by Uli Leonhardt. In 2018, it was reported as a thirteenth specimen of ''Archaeopteryx''. Subsequent research, however, indicated that it represented a species new to science. In 2019, the type species ''Alcmonavis poeschli'' was named and described by Oliver Walter Mischa Rauhut, Helmut Tischlinger and Christian Foth. The generic name combines the old Celtic name of the Altmühl River meandering through the region of the find, Alcmona, with a Lati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Archaeopterygidae
Archaeopterygidae is a group of maniraptoran dinosaurs, known from the latest Jurassic and earliest Cretaceous of Europe. In most current classifications, it contains only the genera ''Archaeopteryx'' and ''Wellnhoferia''. As its name suggests, ''Protarchaeopteryx'' was also once referred to this group, but most paleontologists now consider it an oviraptorosaur. Other referred genera, like '' Jurapteryx'', ''Wellnhoferia'', and " Proornis", are probably synonymous with ''Archaeopteryx'' (the former two) or do not belong into this group (the last). ''Jinfengopteryx'' was originally described as an archaeopterygid, though it was later shown to be a troodontid.Chiappe, L.M. (2007) ''Glorified Dinosaurs: The Origin and Early Evolution of Birds.'' Sydney: UNSW Press. . A few studies have recovered ''Anchiornis'' and ''Xiaotingia'' (usually considered part of a distinct clade, Anchiornithidae) to also be members of the Archaeopterygidae, though most subsequent analyses have failed to arr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rahonavis
''Rahonavis'' is a genus of bird-like theropods from the Late Cretaceous (Maastrichtian, about 70 mya) of what is now northwestern Madagascar. It is known from a partial skeleton ( UA 8656) found by Catherine Forster and colleagues in Maevarano Formation rocks at a quarry near Berivotra, Mahajanga Province.Tudge, Colin (2009) ''The Bird:A Natural History of Who Birds Are, Where They Came From, and How They Live'/ref> ''Rahonavis'' was a small predator, at about long and 0.45-2.27 kg (1-5 lbs),Holtz, Thomas R. Jr. (2008) ''Dinosaurs: The Most Complete, Up-to-Date Encyclopedia for Dinosaur Lovers of All Ages'Supplementary Information/ref> with the typical ''Velociraptor''-like raised sickle claw on the second toe. It was originally the first African coelurosaur until the Nqwebasaurus was discovered in 2000. The name ''Rahonavis'' means, approximately, "cloud menace bird", from Malagasy ' (RA-hoo-na, "cloud" or "menace") + Latin ' "bird". The specific name, ''R. ostromi'', was co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
