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Aeolosaurinae
Aeolosaurini is an extinct clade of titanosaurian dinosaurs known from the Cretaceous period of Argentina and Brazil. Rodrigo M. Santucci and Antonio C. de Arruda-Campos (2011) in their cladistic analysis found '' Aeolosaurus'', ''Gondwanatitan'', ''Maxakalisaurus'', ''Panamericansaurus'' and ''Rinconsaurus'' to be aeolosaurids. Aeolosaurini is characterized by several synapomorphies of the caudal vertebrae, such as angled centra, elongate prezygapophyses, and neural arches shifted anteriorly relative to the centra. In life, their tails may have been strongly curved downward as a result of these traits, which may have increased the force exerted by the caudofemoralis longus muscle in retracting the hindlimb. Some aeolosaurins, such as ''Shingopana'' and ''Overosaurus'', were relatively small compared to other titanosaurs, whereas others, such as ''Aeolosaurus maximus'', were large. Phylogeny Aeolosaurini was defined by Franco-Rosas, Salgado, Rosas and Carvalho (2004) as the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lithostrotia
Lithostrotia is a clade of derived titanosaur sauropods that lived during the Early Cretaceous and Late Cretaceous. The group was defined by Upchurch ''et al.'' in 2004 as the most recent common ancestor of '' Malawisaurus'' and '' Saltasaurus'' and all the descendants of that ancestor. Lithostrotia is derived from the Ancient Greek , meaning "inlaid with stones", referring to the fact that many known lithostrotians are preserved with osteoderms. However, osteoderms are not a distinguishing feature of the group, as the two noted by Unchurch ''et al.'' include caudal vertebrae with strongly concave front faces (procoely), although the farthest vertebrae are not procoelous. History of research In 1895, Richard Lydekker named the family Titanosauridae to summarize sauropods with procoelous (concave on the front) caudal vertebrae. The name Titanosauridae has since been widely used, and was defined by Salgado and colleagues (1997), Gonzalaz-Riga (2003), and Salgado (2003) as a node- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Muyelensaurus
''Muyelensaurus'' (meaning "Muyelen lizard", after an indigenous name for the Colorado River in Argentina) is a genus of titanosaurian sauropod dinosaur from the Late Cretaceous of Argentina. It was more slender than other titanosaurs. Fossils have been recovered from the Plottier Formation in the Neuquén province of Patagonia. The type species is ''M. pecheni''.''Muyelensaurus'' at .org The name ''Muyelensaurus'' first appeared in a 2007 paper by |
Cretaceous
The Cretaceous ( ) is a geological period that lasted from about 145 to 66 million years ago (Mya). It is the third and final period of the Mesozoic Era, as well as the longest. At around 79 million years, it is the longest geological period of the entire Phanerozoic. The name is derived from the Latin ''creta'', " chalk", which is abundant in the latter half of the period. It is usually abbreviated K, for its German translation ''Kreide''. The Cretaceous was a period with a relatively warm climate, resulting in high eustatic sea levels that created numerous shallow inland seas. These oceans and seas were populated with now-extinct marine reptiles, ammonites, and rudists, while dinosaurs continued to dominate on land. The world was ice free, and forests extended to the poles. During this time, new groups of mammals and birds appeared. During the Early Cretaceous, flowering plants appeared and began to rapidly diversify, becoming the dominant group of plants across the Ear ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Synapomorphies
In phylogenetics, an apomorphy (or derived trait) is a novel character or character state that has evolved from its ancestral form (or plesiomorphy). A synapomorphy is an apomorphy shared by two or more taxa and is therefore hypothesized to have evolved in their most recent common ancestor. ) In cladistics, synapomorphy implies homology. Examples of apomorphy are the presence of erect gait, fur, the evolution of three middle ear bones, and mammary glands in mammals but not in other vertebrate animals such as amphibians or reptiles, which have retained their ancestral traits of a sprawling gait and lack of fur. Thus, these derived traits are also synapomorphies of mammals in general as they are not shared by other vertebrate animals. Etymology The word —coined by German entomologist Willi Hennig—is derived from the Ancient Greek words (''sún''), meaning "with, together"; (''apó''), meaning "away from"; and (''morphḗ''), meaning "shape, form". Clade ana ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diamantinasaurus
''Diamantinasaurus'' is a genus of titanosaurian sauropod from Australia that lived during the early Late Cretaceous, about 94 million years ago. The type species of the genus is ''D. matildae'', first described and named in 2009 by Scott Hocknull and colleagues based on fossil finds in the Winton Formation. Meaning "Diamantina lizard", the name is derived from the location of the nearby Diamantina River and the Greek word ''sauros'', "lizard". The specific epithet is from the Australian song Waltzing Matilda, also the locality of the holotype and paratype. The known skeleton includes most of the forelimb, shoulder girdle, pelvis, hindlimb and ribs of the holotype, and one shoulder bone, a radius and some vertebrae of the paratype. History of discovery The holotype of ''Diamantinasaurus'' was first uncovered over four seasons of excavations near Winton, Queensland, Australia. The bones were found alongside the holotype of ''Australovenator'' and crocodylomorphs and molluscs. Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Saltasauroidea
Saltasauroidea is a superfamily of titanosaurs named by França and colleagues in 2016 based on their phylogenetic results, for a clade uniting Aeolosaurini and Saltasauridae, as well as the intermediate genera ''Baurutitan'', ''Diamantinasaurus'' and ''Isisaurus''. The group was not defined or discussed in the text, but was supported by Carballido and colleagues in 2022 as a useful designation for subdividing titanosaurs. As there was no discussion about the intentions for the clade, Carballido gave it the definition of all taxa closer to ''Saltasaurus'' than ''Patagotitan ''Patagotitan'' is a genus of titanosaurian sauropod dinosaur from the Cerro Barcino Formation in Chubut Province, Patagonia, Argentina. The genus contains a single species known from multiple individuals: ''Patagotitan mayorum'', first announc ...'', encompassing half of Eutitanosauria as the sister taxon to the inversely defined Colossosauria. Carballido ''et al.'' placed Nemegtosauridae and Saltasauri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rapetosaurus
''Rapetosaurus'' ( ) is a genus of titanosaurian sauropod dinosaur that lived in Madagascar from 70 to 66 million years ago, at the end of the Cretaceous Period. Only one species, ''Rapetosaurus krausei'', has been identified. Like other sauropods, ''Rapetosaurus'' was a quadrupedal herbivore; it is calculated to have reached lengths of 15 metres (49 ft). Description ''Rapetosaurus'' was a fairly typical sauropod, with a short and slender tail, a very long neck and a huge, elephant-like body. Its head resembles the head of a diplodocid, with a long, narrow snout and nostrils on the top of its skull. It was a herbivore and its small, pencil-like teeth were good for ripping the leaves off trees but not for chewing. It was fairly modest in size, for a titanosaur. The juvenile specimen measured from head to tail, and "probably weighed about as much as an elephant". An adult would have been about twice as long ( in length) which is still less than half the length of its ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tapuiasaurus
''Tapuiasaurus'' (meaning " Tapuia lizard") is a genus of titanosaur which lived during the Lower Cretaceous period (Aptian age) in what is now Minas Gerais, Brazil. Its fossils, including a partial skeleton with a nearly complete skull, have been recovered from the Quiricó Formation of the São Francisco Basin in Minas Gerais, eastern Brazil. This genus was named by Hussam Zaher, Diego Pol, Alberto B. Carvalho, Paulo M. Nascimento, Claudio Riccomini, Peter Larson, Rubén Juárez Valieri, Ricardo Pires Domingues, Nelson Jorge da Silva Jr. and Diógenes de Almeida Campos in 2011, and the type species is ''Tapuiasaurus macedoi''. Classification ''Tapuiasaurus'' was originally assigned to Nemegtosauridae by its original describers, but two subsequent cladistic analyses have recovered it as only distantly related to ''Nemegtosaurus'', with Wilson ''et al.'' (2016) recovering the genus outside the Lithostrotia, and Carballido ''et al.'' (2017) recovering it as closely relat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nemegtosaurus
''Nemegtosaurus'' (meaning 'Reptile from the Nemegt') was a sauropod dinosaur from the Late Cretaceous Period of what is now Mongolia. It was named after the Nemegt Basin in the Gobi Desert, where the remains — a single skull — were found. The skull resembles diplodocoids in being long and low, with pencil-shaped teeth. However, recent work has shown that ''Nemegtosaurus'' is in fact a titanosaur, closely related to animals such as '' Saltasaurus'', '' Alamosaurus'' and '' Rapetosaurus''. Discovery and taxonomy The skull of ''Nemegtosaurus'' comes from the same beds as the titanosaur '' Opisthocoelicaudia'', which is known from a skeleton lacking the neck and skull. Originally, the referral of ''Nemegtosaurus'' to Diplodocoidea and ''Opisthocoelicaudia'' to Camarasauridae argued that the two represented different species. Both of these genera represent advanced titanosaurians, however, raising the possibility that the two are in fact the same animal. Relocation of the ''Neme ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nemegtosauridae
Nemegtosauridae is a family of titanosaurian sauropod dinosaurs based on their diplodocid-like skulls. Only three species are known: ''Nemegtosaurus'', ''Quaesitosaurus'' and possibly ''Tapuiasaurus'', each from the Cretaceous. History of classification Due to the diplodocid-like nature of the taxa placed in Nemegtosauridae, the systematic position of this family in Sauropoda was disputed until recently. McIntosh (1990) included both these animals in the family Diplodocidae, subfamily Dicraeosaurinae, as they resemble the skull of ''Dicraeosaurus'', although differing in certain details. Although the skull of ''Nemegtosaurus'' was found in the same formation as the headless skeleton of ''Opisthocoelicaudia'', McIntosh (1990) kept ''Nemegtosaurus'' in Diplodocoidea while keeping ''Opisthocoelicaudia'' separate from the former, a position reiterated by Upchurch (1995, 1999), and Upchurch et al. (2004). A cladistic analysis published in 2002 transferred ''Nemegtosaurus'' and ''Opist ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Malawisaurus
''Malawisaurus'' (meaning "Malawi lizard") is an extinct genus of titanosaurian sauropod dinosaur. It is known from the Dinosaur Beds of northern Malawi, which probably date to the Aptian stage of the Early Cretaceous. The type species is ''M. dixeyi'' and the specific name honours Frederick Augustus Dixey. Discovery and naming ''Malawisaurus dixeyi'' was originally described in 1928 by Sidney H. Haughton as a species of '' Gigantosaurus'' (an invalid name for the diplodocid currently known as '' Tornieria''). Haughton considered it closely related to the species ''G. robustus'' (later the type species of '' Janenschia''). The holotype was discovered in the " Dinosaur Beds" of Malawi (then known as the Nyasaland Protectorate), which are usually considered to be of Barremian-Aptian age based on K–Ar dating, though they have also been suggested to be Late Cretaceous in age based on the vertebrate assemblage, and possibly also the Lupata Group. In 1993 it was placed in the n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cladogram
A cladogram (from Greek ''clados'' "branch" and ''gramma'' "character") is a diagram used in cladistics to show relations among organisms. A cladogram is not, however, an evolutionary tree because it does not show how ancestors are related to descendants, nor does it show how much they have changed, so many differing evolutionary trees can be consistent with the same cladogram. A cladogram uses lines that branch off in different directions ending at a clade, a group of organisms with a last common ancestor. There are many shapes of cladograms but they all have lines that branch off from other lines. The lines can be traced back to where they branch off. These branching off points represent a hypothetical ancestor (not an actual entity) which can be inferred to exhibit the traits shared among the terminal taxa above it. This hypothetical ancestor might then provide clues about the order of evolution of various features, adaptation, and other evolutionary narratives about an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
