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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] |
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] |
Carnian
The Carnian (less commonly, Karnian) is the lowermost stage (stratigraphy), stage of the Upper Triassic series (stratigraphy), Series (or earliest age (geology), age of the Late Triassic Epoch (reference date), Epoch). It lasted from 237 to 227 megaannum, 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 Johann August Georg Edmund Mojsisovics von Mojsvar, Mojsisovics. It is unclear if it was named after the Carnic Alps or after the Austrian region of Carinthia (state), Carinthia (''Kärnten'' in German) or after the Carnia historical region in northwestern Italy. The name, however, was first used re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fremont County, Wyoming
Fremont County is a county in the U.S. state of Wyoming. As of the 2020 United States Census, the population was 39,234, making it the fifth-most populous county in Wyoming. Its county seat is Lander. The county was founded in 1884 and is named for John C. Frémont, a general, explorer, and politician. It is roughly the size of the state of Vermont. Fremont County comprises the Riverton, WY Micropolitan Statistical Area. History Fremont County was created on March 5, 1884 by the legislature of the Wyoming Territory. The county was created with land ceded by Sweetwater County. In 1890, Big Horn County was carved out of Fremont, Johnson, and Sheridan Counties. Hot Springs County was created in 1911 from parts of Fremont, Big Horn, and Park counties. In 1921, Sublette County was created from parts of Fremont and Lincoln counties, leaving Fremont County's boundary at its present configuration. Fremont County was named for John Charles Frémont, an explorer of the American ... [...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 tha ... [...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 ... [...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 ... [...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] |
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] |
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] |
Ischigualastia
''Ischigualastia'' is an extinct genus of large dicynodont therapsids that lived during the Late Carnian age and the Early Norian age of the Late Triassic Period. The genus was found in and named after the Ischigualasto Formation (Cancha de Bochas Member) of the Ischigualasto-Villa Unión Basin in northwestern Argentina. It has been placed in the family Stahleckeriidae. Description The genus is described as an enormous dicynodont, with a short, high skull, and lacking tusks. It is regarded as larger than its later, more famous relative ''Placerias'', which weighed over . Paleoecology It was a large quadrupedal herbivore, most common at the base of the Ischigualasto Formation. It was a common member of the local fauna, although not as abundant as the medium-sized herbivores ''Hyperodapedon'' and ''Exaeretodon''. The only danger to such a huge animal was the almost equally large carnivorous pseudosuchian ''Saurosuchus'' and perhaps the predatory dinosaur ''Herrerasaurus'', ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Placerias Hesternus
''Placerias'' (meaning 'broad body') is an extinct genus of dicynodonts that lived during the Carnian to the Norian age of the Triassic Period (230–220 million years ago). ''Placerias'' belongs to a group of dicynodonts called Kannemeyeriiformes, which was the last known group of dicynodonts before the taxon became extinct at the end of the Triassic. Description ''Placerias'' was one of the largest herbivores in the Late Triassic, with large skull measuring long and weighing up to with a powerful neck, strong legs, and a barrel-shaped body. There are possible ecological and evolutionary parallels with the modern hippopotamus, spending much of its time during the wet season wallowing in the water, chewing at bankside vegetation. Remaining in the water would also have given ''Placerias'' some protection against land-based predators such as '' Postosuchus''. ''Placerias'' used its beak to slice through thick branches and roots with two short tusks that could be used for defenc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
