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Arackar
''Arackar'' (meaning "skeleton" in Kunza) is an extinct genus of lithostrotian sauropod, possibly part of the Saltasauridae, discovered in the Hornitos Formation of Atacama Province, Chile. The genus contains a single species, ''Arackar licanantay'', described by Rubilar-Rogers ''et al.'' in 2021. Discovery and naming The holotype was discovered in 1993 at Quebrada La Higuera, approximately 75 km (47 mi) south of Copiapó. The fossil material was briefly mentioned by Rubilar-Rogers & Gutstein in 2012 and was found to not be referable to the genus ''Atacamatitan''. In 2021, ''Arackar licanantay'' was named and described by David Rubilar-Rogers, Alexander O. Vargas, Bernardo González Riga, Sergio Soto-Acuña, Jhonatan Alarcón-Muñoz, José Iriarte-Díaz, Carlos Arévalo and Carolina S. Gutstein. The holotype, SNGM-1, was found in a layer of the Hornitos Formation in Chile that dates back to the Late Cretaceous period ( Campanian-Maastrichtian stages). It includes vertebrae of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arackar Vetrebrae
''Arackar'' (meaning "skeleton" in Kunza) is an extinct genus of lithostrotian sauropod, possibly part of the Saltasauridae, discovered in the Hornitos Formation of Atacama Province, Chile. The genus contains a single species, ''Arackar licanantay'', described by Rubilar-Rogers ''et al.'' in 2021. Discovery and naming The holotype was discovered in 1993 at Quebrada La Higuera, approximately 75 km (47 mi) south of Copiapó. The fossil material was briefly mentioned by Rubilar-Rogers & Gutstein in 2012 and was found to not be referable to the genus ''Atacamatitan''. In 2021, ''Arackar licanantay'' was named and described by David Rubilar-Rogers, Alexander O. Vargas, Bernardo González Riga, Sergio Soto-Acuña, Jhonatan Alarcón-Muñoz, José Iriarte-Díaz, Carlos Arévalo and Carolina S. Gutstein. The holotype, SNGM-1, was found in a layer of the Hornitos Formation in Chile that dates back to the Late Cretaceous period ( Campanian-Maastrichtian stages). It includes vertebrae of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2021 In Archosaur Paleontology
This article records new taxa of fossil archosaurs of every kind that are scheduled binomial nomenclature, described during the year 2021, as well as other significant discoveries and events related to paleontology of archosaurs that are scheduled to occur in the year 2021. General research * A study on the relationship between full potential joint mobility and the poses used during locomotion in extant American alligator and helmeted guineafowl, evaluating its implications for reconstructions of locomotion of extinct archosaurs, is published by Manafzadeh, Kambic & Gatesy (2021). * A study on the Femur, femoral shape variation and on the relationship between femoral morphology and locomotor habits in early archosaurs and non-archosaur Archosauriformes, archosauriforms is published by Pintore ''et al.'' (2021). * A study estimating moment arms for major Pelvis, pelvic limb muscles in extant and fossil archosaurs, aiming to investigate the idea that bird-line archosaurs switched fr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hornitos Formation
The Hornitos Formation is a Campanian geologic formation of the Algarrobal Basin in the Atacama Region of northern Chile. The formation comprises limestones, sandstones, conglomerates, marls and tuff. Dinosaur remains are among the fossils that have been recovered from the formation, including the sauropod '' Arackar licanantay''.Weishampel, et al. (2004). "Dinosaur distribution." pp. 517–607. Description The Hornillos Formation, deposited in the Algarrobal Basin,Abad, 1982, p. 5 comprises sandstones, limestones, conglomerates, and caliches, intercalated with lavas and andesitic breccias and various volcanic rocks. Between these last is a conspicuous layer of rhyo- dactitic lithic tuff, which reaches up to in thickness. Bones of indeterminate titanosaurs appear in a marly limestone stratum of thick with decimeter-sized calcareous concretions. The smallest pieces were found as rollings, whereas the larger piece was included in the limestone. [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Titanosauria
Titanosaurs (or titanosaurians; members of the group Titanosauria) were a diverse group of sauropod dinosaurs, including genera from all seven continents. The titanosaurs were the last surviving group of long-necked sauropods, with taxa still thriving at the time of the extinction event at the end of the Cretaceous. This group includes some of the largest land animals known to have ever existed, such as ''Patagotitan''—estimated at long with a weight of —and the comparably-sized ''Argentinosaurus'' and ''Puertasaurus'' from the same region. The group's name alludes to the mythological Titans of ancient Greek mythology, via the type genus (now considered a ''nomen dubium)'' ''Titanosaurus''. Together with the brachiosaurids and relatives, titanosaurs make up the larger sauropod clade Titanosauriformes. Titanosaurs have long been a poorly-known group, and the relationships between titanosaur species are still not well-understood. Description Titanosauria have the largest ran ... [...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] |
Ischium
The ischium () forms the lower and back region of the (''os coxae''). Situated below the ilium and behind the pubis, it is one of three regions whose fusion creates the . The superior portion of this region forms approximately one-third of the acetabulum. |
Baurutitan
''Baurutitan'' is a genus of sauropod dinosaur that lived during the Late Cretaceous in what is now Brazil. The type species, ''Baurutitan britoi'', was described in 2005 by Kellner and colleagues, although the fossil remains had already been discovered in 1957. ''Baurutitan'' is classified as a lithostrotian titanosaur, and is distinguished from related genera based on its distinctive caudal vertebrae. This South American dinosaur was found in the Serra da Galga Formation near Uberaba, in the Brazilian state of Minas Gerais. Discovery The holotype of ''Baurutitan'' were found in 1957 by Llewellyn Ivor Price, the famous Brazilian paleontologist, in the region of Peirópolis, Minas Gerais. However, it was not until 2005 that ''Baurutitan'' was officially published and named. The works of Price in Peirópolis began in 1947 after Jesuíno Felicíssimo Junior, from the Instituto Geográfico e Geológico of São Paulo, told him about the presence of fossils in the region. Price then ... [...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 newly na ... [...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] |
Clade
A clade (), also known as a monophyletic group or natural group, is a group of organisms that are monophyletic – that is, composed of a common ancestor and all its lineal descendants – on a phylogenetic tree. Rather than the English term, the equivalent Latin term ''cladus'' (plural ''cladi'') is often used in taxonomical literature. The common ancestor may be an individual, a population, or a species (extinct or 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 taxa that are not clades; that is, taxa that are not monophyletic. Some of the relationships between organisms ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isisaurus
''Isisaurus'' (named after the Indian Statistical Institute) is a genus of titanosaurian dinosaur from the Late Cretaceous Lameta Formation of India. The genus contains a single species, ''Isisaurus colberti''. Discovery and Naming The type specimen of ''Isisaurus colberti'', ISI R 335/1-65, was originally described and named as ''Titanosaurus colberti'' by Sohan Lal Jain and Saswati Bandyopadhyay in 1997. The specific name honours Edwin Harris Colbert. In 2003, the fossils were designated as belonging to its own genus by Wilson and Upchurch. The generic name, "''Isisaurus''," combines a reference to the Indian Statistical Institute (ISI) with the Greek "saurus," meaning "lizard." It had a short, vertically directed neck and long forelimbs, making it considerably different from other sauropods. The humerus is 148 centimetres long. ''Isisaurus'' is known from better remains than many other titanosaurs that were known at the time of its description. Much of its postcranial ske ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sister Taxon
In phylogenetics, a sister group or sister taxon, also called an adelphotaxon, comprises the closest relative(s) of another given unit in an evolutionary tree. Definition The expression is most easily illustrated by a cladogram: Taxon A and taxon B are sister groups to each other. Taxa A and B, together with any other extant or extinct descendants of their most recent common ancestor (MRCA), form a monophyletic group, the clade AB. Clade AB and taxon C are also sister groups. Taxa A, B, and C, together with all other descendants of their MRCA form the clade ABC. The whole clade ABC is itself a subtree of a larger tree which offers yet more sister group relationships, both among the leaves and among larger, more deeply rooted clades. The tree structure shown connects through its root to the rest of the universal tree of life. In cladistic standards, taxa A, B, and C may represent specimens, species, genera, or any other taxonomic units. If A and B are at the same taxonomi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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