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Eubrachiosaurus
''Eubrachiosaurus'' is an extinct genus of stahleckeriid dicynodont known from the Late Triassic (Carnian stage) of Wyoming, United States. Description ''Eubrachiosaurus'' is known only from the holotype specimen Field Museum of Natural History, FMNH UC 633, a partial left scapula as well as a left humerus, and left pelvis which have been lost. It was collected at the Little Popo Agie River, near Lander, Fremont County, Wyoming, Fremont County from the Popo Agie Formation of the Chugwater Group. ''Eubrachiosaurus browni'' was first described and named by Samuel Wendell Williston in 1904 in paleontology, 1904 along with ''Brachybrachium brevipes''. Lucas and Hunt (1993) considered both taxa junior synonyms of ''Placerias hesternus'', which is known from the same formation, a position maintained in most subsequent studies. The synonymy of ''Eubrachiosaurus'' and ''Placerias'' was questioned by Long and Murry (1995) who noted that the ectepicondyle of ''Eubrachiosaurus'' was enlarg ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brachybrachium
''Eubrachiosaurus'' is an extinct genus of stahleckeriid dicynodont known from the Late Triassic (Carnian stage) of Wyoming, United States. Description ''Eubrachiosaurus'' is known only from the holotype specimen Field Museum of Natural History, FMNH UC 633, a partial left scapula as well as a left humerus, and left pelvis which have been lost. It was collected at the Little Popo Agie River, near Lander, Fremont County, Wyoming, Fremont County from the Popo Agie Formation of the Chugwater Group. ''Eubrachiosaurus browni'' was first described and named by Samuel Wendell Williston in 1904 in paleontology, 1904 along with ''Brachybrachium brevipes''. Lucas and Hunt (1993) considered both taxa junior synonyms of ''Placerias hesternus'', which is known from the same formation, a position maintained in most subsequent studies. The synonymy of ''Eubrachiosaurus'' and ''Placerias'' was questioned by Long and Murry (1995) who noted that the ectepicondyle of ''Eubrachiosaurus'' was enlarg ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stahleckeriinae
Stahleckeriidae is a family of dicynodont therapsids whose fossils are known from the Triassic of North America, South America, Asia and Africa. Classification Phylogeny Below is a 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 ... from Kammerer ''et al.'' (2013): Genera References Kannemeyeriiformes Induan first appearances Norian extinctions Prehistoric therapsid families {{anomodont-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stahleckeriid
Stahleckeriidae is a family of dicynodont therapsids whose fossils are known from the Triassic of North America, South America, Asia and Africa. Classification Phylogeny Below is a 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 ... from Kammerer ''et al.'' (2013): Genera References Kannemeyeriiformes Induan first appearances Norian extinctions Prehistoric therapsid families {{anomodont-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dicynodont
Dicynodontia is an extinct clade of anomodonts, an extinct type of non-mammalian therapsid. Dicynodonts were herbivorous animals with a pair of tusks, hence their name, which means 'two dog tooth'. Members of the group possessed a horny, typically toothless beak, unique amongst all synapsids. Dicynodonts first appeared in Southern Pangaea during the mid-Permian, ca. 270–260 million years ago, and became globally distributed and the dominant herbivorous animals in the Late Permian, ca. 260–252 Mya. They were devastated by the end-Permian Extinction that wiped out most other therapsids ca. 252 Mya. They rebounded during the Triassic but died out towards the end of that period. They were the most successful and diverse of the non-mammalian therapsids, with over 70 genera known, varying from rat-sized burrowers to elephant-sized browsers. Characteristics The dicynodont skull is highly specialised, light but strong, with the synapsid temporal openings at the rear of the skull ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Popo Agie Formation
The Popo Agie Formation is a Triassic geologic formation that crops out in western Wyoming, western Colorado, and Utah. It was deposited during the Late Triassic in fluvial (river) and lacustrine (lake) environments that existed across much of what is now the American southwest. Fragmentary fossils of prehistoric reptiles and amphibians, including pseudosuchian reptiles and temnospondyl amphibians, have been discovered in the Popo Agie Formation. Dinosaur remains are also among the fossils that have been recovered from the formation, although none have yet been referred to a specific genus.Weishampel, et al. (2004). "Dinosaur distribution." Pp. 517-607. Paleobiota Amphibians Reptiles Synapsids See also * List of dinosaur-bearing rock formations ** List of stratigraphic units with indeterminate dinosaur fossils This list of stratigraphic units with indeterminate dinosaur fossils includes stratigraphic units of formation rank or higher that have produced dinosaur body ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kannemeyeriiformes
Kannemeyeriiformes is a group of large-bodied Triassic dicynodonts. As a clade, Kannemeyeriiformes has been defined to include the species ''Kannemeyeria simocephalus'' and all dicynodonts more closely related to it than to the species '' Lystrosaurus murrayi''. Evolutionary history Despite being the most species-rich group of dicynodonts in the Triassic Period, kannemeyeriiforms exhibit much less diversity in terms of their anatomy and ecological roles than the dicynodonts from the Permian Period. Lystrosauridae is thought to be the most closely related group (sister taxon) to Kannemeyeriiformes, and since the earliest lystrosaurids are known from the Late Permian, the divergence of these two groups must have occurred at least as far back as this time, implying that a long ghost lineage must exist. Although no kannemeyeriiforms have been found in the Late Permian yet, the recent discovery of ''Sungeodon'' helps fill a gap in the early fossil record of the group by showing that k ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kannemeyeriiform
Kannemeyeriiformes is a group of large-bodied Triassic dicynodonts. As a clade, Kannemeyeriiformes has been defined to include the species ''Kannemeyeria simocephalus'' and all dicynodonts more closely related to it than to the species '' Lystrosaurus murrayi''. Evolutionary history Despite being the most species-rich group of dicynodonts in the Triassic Period, kannemeyeriiforms exhibit much less diversity in terms of their anatomy and ecological roles than the dicynodonts from the Permian Period. Lystrosauridae is thought to be the most closely related group (sister taxon) to Kannemeyeriiformes, and since the earliest lystrosaurids are known from the Late Permian, the divergence of these two groups must have occurred at least as far back as this time, implying that a long ghost lineage must exist. Although no kannemeyeriiforms have been found in the Late Permian yet, the recent discovery of ''Sungeodon'' helps fill a gap in the early fossil record of the group by showing that ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carnian
The Carnian (less commonly, Karnian) is the lowermost stage of the Upper Triassic Series (or earliest age of the Late Triassic Epoch). It lasted from 237 to 227 million years ago (Ma). The Carnian is preceded by the Ladinian and is followed by the Norian. Its boundaries are not characterized by major extinctions or biotic turnovers, but a climatic event (known as the Carnian pluvial episode characterized by substantial rainfall) occurred during the Carnian and seems to be associated with important extinctions or biotic radiations. Stratigraphic definitions The Carnian was named in 1869 by Mojsisovics. It is unclear if it was named after the Carnic Alps or after the Austrian region of Carinthia (''Kärnten'' in German) or after the Carnia historical region in northwestern Italy. The name, however, was first used referring to a part of the Hallstatt Limestone cropping out in Austria. The base of the Carnian Stage is defined as the place in the stratigraphic record where t ... [...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] |
Apomorphy
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 analysis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Synonym (taxonomy)
The Botanical and Zoological Codes of nomenclature treat the concept of synonymy differently. * In botanical nomenclature, a synonym is a scientific name that applies to a taxon that (now) goes by a different scientific name. For example, Linnaeus was the first to give a scientific name (under the currently used system of scientific nomenclature) to the Norway spruce, which he called ''Pinus abies''. This name is no longer in use, so it is now a synonym of the current scientific name, ''Picea abies''. * In zoology, moving a species from one genus to another results in a different binomen, but the name is considered an alternative combination rather than a synonym. The concept of synonymy in zoology is reserved for two names at the same rank that refers to a taxon at that rank - for example, the name ''Papilio prorsa'' Linnaeus, 1758 is a junior synonym of ''Papilio levana'' Linnaeus, 1758, being names for different seasonal forms of the species now referred to as ''Araschnia le ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sangusaurus
''Sangusaurus'' is an extinct genus of large dicynodont synapsid with two recognized species: ''S. edentatus'' (the type species) and ''S. parringtonii''. ''Sangusaurus'' is named after the Sangu stream in eastern Zambia near to where it was first discovered + ‘saur’ which is the Greek root for lizard. ''Sangusaurus'' fossils have been recovered from the upper parts of the Ntawere Formation in Zambia and of the Lifua Member of the Manda Beds in Tanzania. The earliest study considered ''Sangusaurus'' a kannemeyeriid dicynodont, but more recent phylogenetic analyses place ''Sangusaurus'' within the stahleckeriid clade of Dicynodontia. Until recently, little work had been done to describe ''Sangusaurus'', likely due to the fact that only four incomplete fossil specimens have been discovered. Discovery The first ''Sangusaurus'' fossil was found in 1963 during a joint paleontological expedition of the British Museum (Natural History) and the University of London. Cox first named ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
