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Quetzalcoatlus Northropi
''Quetzalcoatlus'' is a genus of pterosaur known from the Late Cretaceous period of North America (Maastrichtian stage); its members were among the largest known flying animals of all time. ''Quetzalcoatlus'' is a member of the Azhdarchidae, a family of advanced toothless pterosaurs with unusually long, stiffened necks. Its name comes from the Aztec feathered serpent god Quetzalcoatl. The type species is ''Q. northropi'', named by Douglas Lawson in 1975; the genus also includes the smaller species ''Q. lawsoni'', which was known for many years as an unnamed species before being named by Brian Andres and Wann Langston Jr. (posthumously) in 2021. Discovery and species The first ''Quetzalcoatlus'' fossils were discovered in Texas, United States, from the Maastrichtian Javelina Formation at Big Bend National Park (dated to around 68 million years ago) in 1971 by Douglas A. Lawson, then a geology graduate student from the Jackson School of Geosciences at the University of Texas at ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Javelina Formation
The Javelina Formation is a geological formation in Texas. Dating has shown that the strata date to the Maastrichtian stage of the Late Cretaceous, approximately 70 to 66.5 million years old. The middle part of the formation has been dated to about 69 million years ago plus or minus 1 million years and the top situated near the Cretaceous–Paleogene boundary (in the overlying Black Peaks FormationWoodward, H. N. (2005). Bone histology of the sauropod dinosaur Alamosaurus sanjuanensis from the Javelina Formation, Big Bend National Park, Texas.), dated to 66 Ma ago. Dinosaur remains are among the fossils that have been recovered from the formation.Weishampel, David B; et al. (2004). "Dinosaur distribution (Late Cretaceous, North America)." In: Weishampel, David B.; Dodson, Peter; and Osmólska, Halszka (eds.): The Dinosauria, 2nd, Berkeley: University of California Press. Pp. 574-588. . Age The typical age range of the Javelina Formation has been difficult to determine. Only one ... [...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] |
Holotype
A holotype is a single physical example (or illustration) of an organism, known to have been used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of several examples, but explicitly designated as the holotype. Under the International Code of Zoological Nomenclature (ICZN), a holotype is one of several kinds of name-bearing types. In the International Code of Nomenclature for algae, fungi, and plants (ICN) and ICZN, the definitions of types are similar in intent but not identical in terminology or underlying concept. For example, the holotype for the butterfly '' Plebejus idas longinus'' is a preserved specimen of that subspecies, held by the Museum of Comparative Zoology at Harvard University. In botany, an isotype is a duplicate of the holotype, where holotype and isotypes are often pieces from the same individual plant or samples from the same gathering. A holotype is not necessarily "typ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tyrannosaurus
''Tyrannosaurus'' is a genus of large theropoda, theropod dinosaur. The species ''Tyrannosaurus rex'' (''rex'' meaning "king" in Latin), often called ''T. rex'' or colloquially ''T-Rex'', is one of the best represented theropods. ''Tyrannosaurus'' lived throughout what is now western North America, on what was then an island continent known as Laramidia. ''Tyrannosaurus'' had a much wider range than other Tyrannosauridae, tyrannosaurids. Fossils are found in a variety of geologic formation, rock formations dating to the Maastrichtian Age (geology), age of the Upper Cretaceous Period (geology), period, 68 to 66 mya (unit), million years ago. It was the last known member of the tyrannosaurids and among the last non-aves, avian dinosaurs to exist before the Cretaceous–Paleogene extinction event. Like other tyrannosaurids, ''Tyrannosaurus'' was a bipedal carnivore with a massive skull balanced by a long, heavy tail. Relative to its large and powerful hind limbs, the foreli ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hell Creek Formation
The Hell Creek Formation is an intensively studied division of mostly Upper Cretaceous and some lower Paleocene rocks in North America, named for exposures studied along Hell Creek, near Jordan, Montana. The formation stretches over portions of Montana, North Dakota, South Dakota, and Wyoming. In Montana, the Hell Creek Formation overlies the Fox Hills Formation. The site of Pompeys Pillar National Monument is a small isolated section of the Hell Creek Formation. In 1966, the Hell Creek Fossil Area was designated as a National Natural Landmark by the National Park Service. It is a series of fresh and brackish-water clays, mudstones, and sandstones deposited during the Maastrichtian and Danian (respectively, the end of the Cretaceous period and the beginning of the Paleogene) by fluvial activity in fluctuating river channels and deltas and very occasional peaty swamp deposits along the low-lying eastern continental margin fronting the late Cretaceous Western Interior Seaway. Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nomen Dubium
In binomial nomenclature, a ''nomen dubium'' (Latin for "doubtful name", plural ''nomina dubia'') is a scientific name that is of unknown or doubtful application. Zoology In case of a ''nomen dubium'' it may be impossible to determine whether a specimen belongs to that group or not. This may happen if the original type series (i. e. holotype, isotype, syntype or paratype) is lost or destroyed. The zoological and botanical codes allow for a new type specimen, or neotype, to be chosen in this case. A name may also be considered a ''nomen dubium'' if its name-bearing type is fragmentary or lacking important diagnostic features (this is often the case for species known only as fossils). To preserve stability of names, the ''International Code of Zoological Nomenclature'' allows a new type specimen, or neotype, to be chosen for a ''nomen dubium'' in this case. 75.5. Replacement of unidentifiable name-bearing type by a neotype. When an author considers that the taxonomic identity of a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hatzegopteryx
''Hatzegopteryx'' ("Hațeg basin wing") is a genus of azhdarchid pterosaur found in the late Maastrichtian deposits of the Densuş Ciula Formation, an outcropping in Transylvania, Romania. It is known only from the type species, ''Hatzegopteryx thambema'', named by Buffetaut ''et al.'' in 2002 based on parts of the skull and humerus. Additional specimens, including a neck vertebra, were later placed in the genus, representing a range of sizes. The largest of these remains indicate it was among the biggest pterosaurs, with an estimated wingspan of . Unusually among giant azhdarchids, ''Hatzegopteryx'' had a very wide skull bearing large muscular attachments; bones with a spongy internal texture instead of hollow; and a short, robust, and heavily muscled neck measuring long, which was about half the length of other azhdarchids with comparable wingspans, and was capable of withstanding strong bending forces. ''Hatzegopteryx'' inhabited Hațeg Island, an island situated in the Cret ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Romania
Romania ( ; ro, România ) is a country located at the crossroads of Central Europe, Central, Eastern Europe, Eastern, and Southeast Europe, Southeastern Europe. It borders Bulgaria to the south, Ukraine to the north, Hungary to the west, Serbia to the southwest, Moldova to the east, and the Black Sea to the southeast. It has a predominantly Temperate climate, temperate-continental climate, and an area of , with a population of around 19 million. Romania is the List of European countries by area, twelfth-largest country in Europe and the List of European Union member states by population, sixth-most populous member state of the European Union. Its capital and largest city is Bucharest, followed by Iași, Cluj-Napoca, Timișoara, Constanța, Craiova, Brașov, and Galați. The Danube, Europe's second-longest river, rises in Germany's Black Forest and flows in a southeasterly direction for , before emptying into Romania's Danube Delta. The Carpathian Mountains, which cross Roma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mark Witton
Mark Paul Witton is a British vertebrate palaeontologist, author, and palaeoartist best known for his research and illustrations concerning pterosaurs, the extinct flying reptiles that lived alongside dinosaurs. He has worked with museums and universities around the world to reconstruct extinct animals, including as consultant to the ''Walking with Dinosaurs'' franchise and BBC's ''Planet Dinosaur'', and has published several critically acclaimed books on palaeontology and palaeoart. Witton obtained a palaeobiology and evolution degree, his Ph.D., from the University of Portsmouth, where he currently works as support staff. Witton's scientific research has revolved largely around the habits, behaviors, systematics and nomenclature of pterosaurs. His 2013 book ''Pterosaurs: Natural History, Evolution, Anatomy'' explores the anatomy, ecology and extinction of pterosaurs, in addition to being fully illustrated. Witton's palaeoart Paleoart (also spelled palaeoart, paleo-art, o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alexander Kellner
Alexander Wilhelm Armin Kellner (born September 26, 1961) is a Brazilian geologist and paleontologist who is a leading expert in the field of studying pterosaurs. His research has focused mainly on fossil reptiles from the Cretaceous Period, including extinct dinosaurs and crocodylomorphs. Kellner has over 500 publications to his name, has published more than 160 primary studies and two science books. He has participated in paleontological expeditions to many locations including Brazil, Chile, Iran, the United States, Argentina, China, and Antarctica. His scientific achievements include the description of more than thirty species. For his work he has received several honors and prizes, including the TWAS Prize for Earth Sciences from The World Academy of Sciences and admission to the National Order of Scientific Merit (class Comendador), one Brazil's most prestigious awards. Biography Kellner was born in Vaduz, Liechtenstein, son of a German father and Austrian mother. In hi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quetzalcoatlus Sp
''Quetzalcoatlus'' is a genus of pterosaur known from the Late Cretaceous period of North America (Maastrichtian stage); its members were among the largest known flying animals of all time. ''Quetzalcoatlus'' is a member of the Azhdarchidae, a family of advanced toothless pterosaurs with unusually long, stiffened necks. Its name comes from the Aztec feathered serpent god Quetzalcoatl. The type species is ''Q. northropi'', named by Douglas Lawson in 1975; the genus also includes the smaller species ''Q. lawsoni'', which was known for many years as an unnamed species before being named by Brian Andres and Wann Langston Jr. (posthumously) in 2021. Discovery and species The first ''Quetzalcoatlus'' fossils were discovered in Texas, United States, from the Maastrichtian Javelina Formation at Big Bend National Park (dated to around 68 million years ago) in 1971 by Douglas A. Lawson, then a geology graduate student from the Jackson School of Geosciences at the University of Texas a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flying Wing
A flying wing is a tailless fixed-wing aircraft that has no definite fuselage, with its crew, payload, fuel, and equipment housed inside the main wing structure. A flying wing may have various small protuberances such as pods, nacelles, blisters, booms, or vertical stabilizers. Similar aircraft designs, that are not technically flying wings, are sometimes casually referred to as such. These types include blended wing body aircraft and lifting body aircraft, which have a fuselage and no definite wings. A pure flying wing is theoretically the lowest drag design configuration for a fixed wing aircraft. However, because it lacks conventional stabilizing surfaces and the associated control surfaces, in its purest form the flying wing suffers from being unstable and difficult to control. The basic flying wing configuration became an object of significant study during the 1920s, often in conjunction with other tailless designs. In the Second World War, both Nazi Germany and the A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
