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Cetiosaurid
Cetiosauridae is a family of sauropod dinosaurs which was first proposed by Richard Lydekker in 1888. While traditionally a wastebasket taxon containing various unrelated species, some recent studies have found that it may represent a natural 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, .... Alongside '' Cetiosaurus'' from the Middle Jurassic of Britain, other taxa recently assigned to the family include '' Lapparentosaurus'' from the Middle Jurassic of Madagascar, and '' Patagosaurus'' from the late Early-Middle Jurassic of Patagonia, which share autapomorphies with ''Cetiosaurus'' that are not shared by other eusauropods. Additionally, at least one study has suggested that the mamenchisaurids may represent a sub-group of the cetiosaurids, which would be termed Mamench ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Patagosaurus
''Patagosaurus'' (meaning "Patagonia lizard") is an extinct genus of eusauropod dinosaur from the Middle-Late Toarcian of Patagonia, Argentina. It was first found in deposits of the Cañadón Asfalto Formation, which date to around 179 to 177 million years ago. Although originally twelve specimens were assigned to the taxon, at least one of them may belong to a different genus. ''Patagosaurus'' probably lived alongside genera as ''Piatnitzkysaurus'', ''Condorraptor'' and ''Volkheimeria''. Since ''Patagosaurus'' is known from many specimens, including at least one juvenile, its anatomy and growth are fairly well understood. Both ages exhibit the typical features of a sauropod, a long neck, small head, a long tail and being quadrupedal. The juvenile exhibits features different from the adult in regions like the mandible, pectoral girdle, pelvis and hindlimb, although overall their anatomy is quite similar. The many known specimens help fill in gaps in the anatomy of the genus, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cetiosauridae
Cetiosauridae is a family of sauropod dinosaurs which was first proposed by Richard Lydekker in 1888. While traditionally a wastebasket taxon containing various unrelated species, some recent studies have found that it may represent a natural clade. Alongside ''Cetiosaurus'' from the Middle Jurassic of Britain, other taxa recently assigned to the family include ''Lapparentosaurus'' from the Middle Jurassic of Madagascar, and ''Patagosaurus'' from the late Early-Middle Jurassic of Patagonia, which share autapomorphies with ''Cetiosaurus'' that are not shared by other eusauropods. Additionally, at least one study has suggested that the mamenchisaurids Mamenchisauridae is a family of sauropod dinosaurs belonging to Eusauropoda known from the Jurassic and Early Cretaceous of Asia and Africa. Some members of the group reached gigantic sizes, amongst the largest of all sauropods. Classification T ... may represent a sub-group of the cetiosaurids, which would be termed Mamenchisau ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lapparentosaurus
''Lapparentosaurus'' is a genus of sauropod dinosaur from the Middle Jurassic. Its fossils were found in Madagascar (Isalo III Formation). The type species is ''L. madagascariensis''. Discovery and naming In 1895 Richard Lydekker named a new species of ''Bothriospondylus'', ''B. madagascariensis'' based on fossils found before 1894 by Joseph Thomas Last in the Majunga Basin in layers of the Bathonian, the Isalo III Formation. Because there was no real connection with this English form, in 1986 José Fernando Bonaparte named a separate genus. The type species, the only known, is ''Lapparentosaurus madagascariensis''. The generic name honours Albert-Félix de Lapparent. The holotype assigned by Bonaparte, MAA 91-92, consists of two neural arches. Much more abundant material has been referred, from at least three but perhaps as much as ten individuals from different growth stages. This includes vertebrae and limb elements but no skulls. The species is still lacking a good descri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chebsaurus
''Chebsaurus'' is a genus of quadrupedal, herbivorous, cetiosaurid sauropod dinosaur, specifically a eusauropod. It lived in present-day Algeria, in the Callovian aged Aïssa Formation. The type species, ''C. algeriensis'', was named in 2005 by Mahammed et al. and is the most complete Algerian sauropod known. It was around long. The word "Cheb" "شاب" is colloquial Arabic Arabic (, ' ; , ' or ) is a Semitic language spoken primarily across the Arab world.Semitic languages: an international handbook / edited by Stefan Weninger; in collaboration with Geoffrey Khan, Michael P. Streck, Janet C. E.Watson; Walter ... for "young man", as the fossils found were believed to be from a juvenile. The original publication, by Mahammed et al., gives ''Chebsaurus'' the nickname "the Giant of Ksour". A second skeleton, also from a juvenile of a similar ontogenetic stage, is also known. Both skeletons, including cranial material, was found in the Ksour Mountains, part of the Oc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rutellum
This list of informally named dinosaurs is a listing of dinosaurs (excluding Aves; birds and their extinct relatives) that have never been given formally published scientific names. This list only includes names that were not properly published ("unavailable names") and have not since been published under a valid name (see list of dinosaur genera for valid names). The following types of names are present on this list: * ''Nomen nudum'', Latin for "naked name": A name that has appeared in print but has not yet been formally published by the standards of the International Commission on Zoological Nomenclature. ''Nomina nuda'' (the plural form) are invalid, and are therefore not italicized as a proper generic name would be. * '' Nomen manuscriptum'', Latin for "manuscript name": A name that appears in manuscript but was not formally published. A ''nomen manuscriptum'' is equivalent to a ''nomen nudum'' for everything except the method of publication, and description. * '' Nomen ex d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eusauropoda
Eusauropoda (meaning "true sauropods") is a derived clade of sauropod dinosaurs. Eusauropods represent the node-based group that includes all descendant sauropods starting with the basal eusauropods of ''Shunosaurus'', and possibly ''Barapasaurus'', and ''Amygdalodon'', but excluding ''Vulcanodon'' and ''Rhoetosaurus''. The Eusauropoda was coined in 1995 by Paul Upchurch to create a monophyletic new taxonomic group that would include all sauropods, except for the vulcanodontids. Eusauropoda are herbivorous, quadrupedal, and have long necks. They have been found in South America, Europe, North America, Asia, Australia, and Africa. The temporal range of Eusauropoda ranges from the early Jurassic to the Latest Cretaceous periods. The most basal forms of eusauropods are not well known and because the cranial material for the ''Vulcanodon'' is not available, and the distribution of some of these shared derived traits that distinguish Eusauropoda is still completely clear. Descriptio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Toarcian
The Toarcian is, in the ICS' geologic timescale, an age and stage in the Early or Lower Jurassic. It spans the time between 182.7 Ma (million years ago) and 174.1 Ma. It follows the Pliensbachian and is followed by the Aalenian. The Toarcian Age began with the Toarcian turnover, the extinction event that sets its fossil faunas apart from the previous Pliensbachian age. It is believed to have ended with a global cooling event known as the Comptum Cooling Event, although whether it represented a worldwide event is controversial. Stratigraphic definitions The Toarcian takes its name from the city of Thouars, just south of Saumur in the Loire Valley of France. The stage was introduced by French palaeontologist Alcide d'Orbigny in 1842, after examining rock strata of this age in a quarry near Thouars. In Europe this period is represented by the upper part of the Lias. The base of the Toarcian is defined as the place in the stratigraphic record where the ammonite genus '' Eoda ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wastebasket Taxon
Wastebasket taxon (also called a wastebin taxon, dustbin taxon or catch-all taxon) is a term used by some taxonomists to refer to a taxon that has the sole purpose of classifying organisms that do not fit anywhere else. They are typically defined by either their designated members' often superficial similarity to each other, or their ''lack'' of one or more distinct character states or by their ''not'' belonging to one or more other taxa. Wastebasket taxa are by definition either paraphyletic or polyphyletic, and are therefore not considered valid taxa under strict cladistic rules of taxonomy. The name of a wastebasket taxon may in some cases be retained as the designation of an evolutionary grade, however. The term was coined in a 1985 essay by Steven Jay Gould. Examples There are many examples of paraphyletic groups, but true "wastebasket" taxa are those that are known not to, and perhaps not intended to, represent natural groups, but are nevertheless used as convenient groups ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Toarcian First Appearances
The Toarcian is, in the ICS' geologic timescale, an age and stage in the Early or Lower Jurassic. It spans the time between 182.7 Ma (million years ago) and 174.1 Ma. It follows the Pliensbachian and is followed by the Aalenian. The Toarcian Age began with the Toarcian turnover, the extinction event that sets its fossil faunas apart from the previous Pliensbachian age. It is believed to have ended with a global cooling event known as the Comptum Cooling Event, although whether it represented a worldwide event is controversial. Stratigraphic definitions The Toarcian takes its name from the city of Thouars, just south of Saumur in the Loire Valley of France. The stage was introduced by French palaeontologist Alcide d'Orbigny in 1842, after examining rock strata of this age in a quarry near Thouars. In Europe this period is represented by the upper part of the Lias. The base of the Toarcian is defined as the place in the stratigraphic record where the ammonite genus '' Eodacty ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mamenchisauridae
Mamenchisauridae is a family of sauropod dinosaurs belonging to Eusauropoda known from the Jurassic and Early Cretaceous of Asia and Africa. Some members of the group reached gigantic sizes, amongst the largest of all sauropods. Classification The family Mamenchisauridae was first erected by Chinese paleontologists Yang Zhongjian ("C.C. Young") and Zhao Xijin in 1972, in a paper describing '' Mamenchisaurus hochuanensis''.Young, C.C. and Zhao, X. (1972). "''Mamenchisaurus hochuanensis sp. nov.''". ''Institute of Vertebrate Palaeontology and Palaeoanthropology Monographs'' Series A 8: 1-30. The most complete cladogram of Mamenchisauridae is presented by Moore ''et al.'', 2020, which includes several named species. Notably, some iterations of their analysis recover ''Euhelopus'' and kin, usually considered somphospondylians, as relatives of mamenchisaurids, mirroring earlier conceptions about the family. Topology A: Implied-weights analysis, Gonzàlez Riga dataset Topology B: Ti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Autapomorphies
In phylogenetics, an autapomorphy is a distinctive feature, known as a derived trait, that is unique to a given taxon. That is, it is found only in one taxon, but not found in any others or outgroup taxa, not even those most closely related to the focal taxon (which may be a species, family or in general any clade). It can therefore be considered an apomorphy in relation to a single taxon. The word ''autapomorphy'', first introduced in 1950 by German entomologist Willi Hennig, is derived from the Greek words αὐτός, ''autos'' "self"; ἀπό, ''apo'' "away from"; and μορφή, ''morphḗ'' = "shape". Discussion Because autapomorphies are only present in a single taxon, they do not convey information about relationship. Therefore, autapomorphies are not useful to infer phylogenetic relationships. However, autapomorphy, like synapomorphy and plesiomorphy is a relative concept depending on the taxon in question. An autapomorphy at a given level may well be a synapomorphy at ... [...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] |
