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Megaraptorans
Megaraptora is a clade of carnivorous theropod dinosaurs. Its Derived (phylogenetics), derived members, the Megaraptoridae are noted for their large hand claws and powerfully-built forelimbs, which are usually reduced in size in other large theropods. Although undoubtedly members of the clade Tetanurae, their relationships to others members of this group have been subject to dispute. Megaraptorans are incompletely known, and no complete megaraptoran skeleton has been found. However, they still possessed a number of unique features. Their forelimbs were large and strongly built, and the Glossary of dinosaur anatomy#ulna, ulna bone had a unique shape in members of the Family (biology), family Megaraptoridae, a subset of megaraptorans which excludes ''Fukuiraptor'' and ''Phuwiangvenator''. The first two fingers were elongated, with massive curved claws, while the third finger was small. Megaraptoran skull material is very incomplete, but a juvenile ''Megaraptor'' described in 2014 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Megaraptor
''Megaraptor'' () is a genus of large Theropoda, theropod dinosaur that lived during the Turonian and Coniacian ages of the Late Cretaceous. Its fossils have been discovered in the Patagonian Portezuelo Formation of Argentina, South America. The type specimen of ''Megaraptor'' consists of a fragmentary assemblage of limb bones, discovered in 1996 by Argentine palaeontologist Fernando Novas, Fernando E. Novas. Believing that a large claw found at the site came from the animal's foot, he determined that it was probably a coelurosaur related to Dromaeosauridae, dromaeosaurs and Troodontidae, troodontids, and named it accordingly. Subsequent discoveries revealed that ''Megaraptor'''s large claw actually came from its hand. The taxonomic position of it and related genera (collectively known as Megaraptora, megaraptorans) is unknown, though it is generally regarded as either a Carnosauria, neovenatorid allosauroid or a Coelurosauria, coelurosaur, possibly related to Tyrannosauroidea, t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Megaraptor Namunhuaiquii
''Megaraptor'' () is a genus of large theropod dinosaur that lived during the Turonian and Coniacian ages of the Late Cretaceous. Its fossils have been discovered in the Patagonian Portezuelo Formation of Argentina, South America. The type specimen of ''Megaraptor'' consists of a fragmentary assemblage of limb bones, discovered in 1996 by Argentine palaeontologist Fernando E. Novas. Believing that a large claw found at the site came from the animal's foot, he determined that it was probably a coelurosaur related to dromaeosaurs and troodontids, and named it accordingly. Subsequent discoveries revealed that ''Megaraptor'''s large claw actually came from its hand. The taxonomic position of it and related genera (collectively known as megaraptorans) is unknown, though it is generally regarded as either a neovenatorid allosauroid or a coelurosaur, possibly related to tyrannosaurs. No complete skeletons of ''Megaraptor'' are known, so its anatomy has been pieced together over the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aerosteon
''Aerosteon'' is a genus of megaraptoran dinosaur from the Late Cretaceous period of Argentina. Its remains were discovered in 1996 in the Anacleto Formation, which is from the late Campanian. The type and only known species is ''A. riocoloradensis''. Its specific name indicates that its remains were found 1 km (0.6 miles) north of the Río Colorado, in Mendoza Province, Argentina. They show evidence of a bird-like respiratory system. ''Aerosteons name can be translated as ''air bone'' and derives from Greek ἀήρ (''aer'', "air") and ὀστέον (''osteon'', "bone"). Discovery ''Aerosteon'' was first discovered in 1996 and was first described by Sereno ''et al.'' in a paper which appeared in the online journal PLoS ONE in September 2008. However, at the time, the International Code of Zoological Nomenclature did not recognize online publication of names for new species as valid unless print copies were also produced and distributed to several libraries, and that ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Australovenator
''Australovenator'' (meaning "southern hunter") is a genus of megaraptoran theropod dinosaur from Cenomanian (Late Cretaceous)-age Winton Formation (dated to 95 million years ago) of Australia. Some specimens from the Albian-aged Eumeralla Formation and the Wonthaggi Formation may belong to ''Australovenator''. It is known from partial cranial and postcranial remains, which were described in 2009 by Scott Hocknull and colleagues, although additional descriptions and analyses continue to be published. It is the most complete predatory dinosaur discovered in Australia. It has been suggested that ''Australovenator'' is a sister taxon to '' Fukuiraptor'', although some phylogenetic analyses find it to be a more derived member of the Megaraptora, possibly being part of the main Megaraptoridae family itself. History of discovery ''Australovenator'' is based on a theropod specimen ( AODF 604), affectionately nicknamed "Banjo" after Banjo Paterson, which was found intermingled ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fukuiraptor
''Fukuiraptor'' ("thief of Fukui") is a genus of medium-sized megaraptoran theropod dinosaur of the Early Cretaceous epoch (either Barremian or Aptian) that lived in what is now Japan. ''Fukuiraptor'' is known from the Kitadani Formation and possibly also the Sebayashi Formation. History The type specimen is a partial skeleton (designated FPDM-V97122) discovered in the Kitadani quarry near Katsuyama in the Fukui prefecture. It is thought that this specimen was not mature and an adult may have been larger. The remains of many other individuals have been found in the quarry, with numerous humeri, femurs, and teeth being assigned to this species. However, the other individuals recovered from the same locality are mostly juveniles that were smaller than the holotype (Currie & Azuma, 2006), in the smallest case less than a quarter of the holotype's size. A tooth (NDC-P0001) discovered in a block of conglomerate from the Sebayashi Formation has been referred to ''Fukuirapto ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tratayenia
''Tratayenia'' is an extinct genus of megaraptoran theropod dinosaurs known from remains found in the Santonian-age Bajo de la Carpa Formation of Argentina. The type and only species, ''Tratayenia rosalesi'', was described in March 2018. ''Tratayenia'' can be distinguished from other megaraptorans on the basis of three autapomorphies (unique derived features) of the front portion of each dorsal vertebra, as well as a single autapomorphy of the sacrum. ''Tratayenia'' is one of the youngest known genera of megaraptorans, having lived only about 83 million years ago. Discovery and naming The holotype consists of a well-preserved partial skeleton, MUCPv 1162, which includes several articulated portions of the backbone. One portion of the skeleton is a string of five dorsal vertebrae, likely the seventh to eleventh dorsals. The largest articulated portion of the skeleton is a string of vertebrae including the last two dorsals as well as the five sacrals and much of the right ilium ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Siats
''Siats'' (/see-ats/) is an extinct genus of large theropod dinosaurs known from the Late Cretaceous Cedar Mountain Formation (Mussentuchit Member) of Utah, United States. The genus contains a single species, ''Siats meekerorum''. It was initially classified as a megaraptoran, a clade of large theropods with controversial relationships. Alternative positions within the Neovenatoridae, Allosauroidea, and Tyrannosauroidea have also been proposed. Discovery and naming ''Siats'' was described by Lindsay E. Zanno and Peter J. Makovicky in 2013. The generic name references a man-eating monster in Ute mythology. The specific name ''meekerorum'' honors the geologist John Caldwell Meeker and his family for their support of paleontological research. ''Siats'' is known from the holotype specimen, FMNH PR 2716, a partial postcranial skeleton housed at the Field Museum of Natural History, Chicago. The specimen consists of five dorsal vertebrae, eight caudal vertebrae, a chevron, a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vectaerovenator
''Vectaerovenator'' (meaning "Isle of Wight air-filled hunter" due to the pneumaticity of the vertebrae) is a genus of tetanuran theropod from the Early Cretaceous period of what is now England (Lower Greensand Group; Ferruginous Sands). It contains one species, ''Vectaerovenator inopinatus''; its holotype, consisting of the specimens IWCMS 2020.400, 2020.407, and 2019.84, comprises two anterior dorsal vertebrae, a cervical vertebra and a mid‐ caudal vertebra from the late Aptian Ferruginous Sands of the Isle of Wight in southern England, discovered in 2019. Comparative anatomical analysis shows that this taxon shares homoplastic features with megalosauroids, carcharodontosaurs, and some coelurosaurs, and cannot be reliably placed beyond Tetanurae ''incertae sedis,'' but has enough autapomorphies that it can be considered a valid genus. Discovery and Naming In 2019, Robin Ward, a regular fossil hunter found material belonging to ''Vectaerovenator'' while on a visit with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Walgettosuchus
''Walgettosuchus'' (meaning "Walgett crocodile") is a dubious or possibly invalid genus of extinct tetanuran theropod dinosaur that lived in Australia during the Late Cretaceous (Cenomanian). It is known from a single caudal vertebra. Discovery and naming An opalised vertebra of a theropod dinosaur was discovered in 1905 by Tullie Cornthwaite Wollaston (May 17, 1863 – July 17, 1931) in an opal bearing sandstone at Lightning Ridge near Walgett, in New South Wales.von Huene, F. (1932). Die fossile Reptil-Ordnung Saurischia, ihte Entwicklung und Geschichte. ''Monographien zur Geologie und Palaeontologie'' 1(4). 361 p. erman/ref> The fossil was sent to the British Museum of Natural History and was reported in January 1909 by Arthur Smith Woodward. Following this, the specimen was briefly described by Woodward in 1910.A.S. Woodward, 1910, "On remains of a megalosaurian dinosaur from New South Wales", ''Report of the British Association for the Advancement of Science'' 79: 482-483 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clade
In biology, a clade (), also known as a Monophyly, monophyletic group or natural group, is a group of organisms that is composed of a common ancestor and all of its descendants. Clades are the fundamental unit of cladistics, a modern approach to taxonomy adopted by most biological fields. The common ancestor may be an individual, a population, or a species (extinct or Extant taxon, extant). Clades are nested, one in another, as each branch in turn splits into smaller branches. These splits reflect evolutionary history as populations diverged and evolved independently. Clades are termed ''monophyletic'' (Greek: "one clan") groups. Over the last few decades, the cladistic approach has revolutionized biological classification and revealed surprising evolutionary relationships among organisms. Increasingly, taxonomists try to avoid naming Taxon, taxa that are not clades; that is, taxa that are not Monophyly, monophyletic. Some of the relationships between organisms that the molecul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Early Cretaceous
The Early Cretaceous (geochronology, geochronological name) or the Lower Cretaceous (chronostratigraphy, chronostratigraphic name) is the earlier or lower of the two major divisions of the Cretaceous. It is usually considered to stretch from 143.1 Megaannum#SI prefix multipliers, Ma to 100.5 Ma. Geology Proposals for the exact age of the Barremian–Aptian boundary ranged from 126 to 117 Ma until recently (as of 2019), but based on drillholes in Svalbard the defining Anoxic event#Cretaceous, early Aptian Oceanic Anoxic Event 1a (OAE1a) was dated to 123.1±0.3 Ma, limiting the possible range for the boundary to c. 122–121 Ma. There is a possible link between this anoxic event and a series of Early Cretaceous large igneous provinces (LIP). The Ontong Java Plateau, Ontong Java-Manihiki Plateau, Manihiki-Hikurangi Plateau, Hikurangi large igneous province, emplaced in the South Pacific at c. 120 Ma, is by far the largest LIP in Earth's history. The Onto ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Theropod
Theropoda (; from ancient Greek , (''therion'') "wild beast"; , (''pous, podos'') "foot"">wiktionary:ποδός"> (''pous, podos'') "foot" is one of the three major groups (clades) of dinosaurs, alongside Ornithischia and Sauropodomorpha. Theropods, both extant and extinct, are characterized by hollow bones and three toes and claws on each limb. They are generally classed as a group of saurischian dinosaurs, placing them closer to sauropodomorphs than to ornithischians. They were ancestrally carnivorous, although a number of theropod groups evolved to become herbivores and omnivores. Members of the subgroup Coelurosauria and possibly some other or all theropods were covered in feathers. In the Jurassic, birds evolved from small specialized coelurosaurian theropods, and are currently represented by about 11,000 living species, making theropods the only group of dinosaurs alive today. Theropods first appeared during the Carnian age of the late Triassic period ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
