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Linhenykus
''Linhenykus'' is an extinct genus of alvarezsaurid theropod dinosaur from the Late Cretaceous of Inner Mongolia, China. It is the most basal known member of the Parvicursorinae. The genus gets its name from Linhe, a city near the site where the fossil was first found and Greek ''nykus'', "claw". The specific name is derived from Greek ''monos'', "single", and ''daktylos'', "finger", a reference to the fact that it is the only known non-avian dinosaur to have had but a single digit. Description ''Linhenykus'' was a small dinosaur, measuring long and weighing . Its femur length is . Alvarezsauroids are known for their short forelimbs, each with a single greatly enlarged second digit. Although alvarezsaurids were once thought to have only a single digit on each forelimb, more recent evidence has shown that most species have reduced third and fourth digits. ''Linhenykus'' is the first known alvarezsaurid to have only a single, second digit. Although a reduced third metacarpal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Linhenykus NT
''Linhenykus'' is an extinct genus of alvarezsaurid theropod dinosaur from the Late Cretaceous of Inner Mongolia, China. It is the most basal known member of the Parvicursorinae. The genus gets its name from Linhe, a city near the site where the fossil was first found and Greek ''nykus'', "claw". The specific name is derived from Greek ''monos'', "single", and ''daktylos'', "finger", a reference to the fact that it is the only known non-avian dinosaur to have had but a single digit. Description ''Linhenykus'' was a small dinosaur, measuring long and weighing . Its femur length is . Alvarezsauroids are known for their short forelimbs, each with a single greatly enlarged second digit. Although alvarezsaurids were once thought to have only a single digit on each forelimb, more recent evidence has shown that most species have reduced third and fourth digits. ''Linhenykus'' is the first known alvarezsaurid to have only a single, second digit. Although a reduced third metacarpal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Linhenykus Monodactylus
''Linhenykus'' is an extinct genus of alvarezsaurid theropod dinosaur from the Late Cretaceous of Inner Mongolia, China. It is the most basal known member of the Parvicursorinae. The genus gets its name from Linhe, a city near the site where the fossil was first found and Greek ''nykus'', "claw". The specific name is derived from Greek ''monos'', "single", and ''daktylos'', "finger", a reference to the fact that it is the only known non-avian dinosaur to have had but a single digit. Description ''Linhenykus'' was a small dinosaur, measuring long and weighing . Its femur length is . Alvarezsauroids are known for their short forelimbs, each with a single greatly enlarged second digit. Although alvarezsaurids were once thought to have only a single digit on each forelimb, more recent evidence has shown that most species have reduced third and fourth digits. ''Linhenykus'' is the first known alvarezsaurid to have only a single, second digit. Although a reduced third metacarpal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parvicursorinae
Alvarezsauridae is a family of small, long-legged dinosaurs. Although originally thought to represent the earliest known flightless birds, they are now thought to be an early diverging branch of maniraptoran theropods. Alvarezsaurids were highly specialized. They had tiny but stout forelimbs, with compact, bird-like hands. Their skeletons suggest that they had massive breast and arm muscles, possibly adapted for digging or tearing. They had long, tube-shaped snouts filled with tiny teeth. They have been interpreted as myrmecophagous, adapted to prey on colonial insects such as termites, with the short arms acting as effective digging instruments to break into nests. ''Alvarezsaurus'', the type genus of the family, was named for the historian Gregorio Álvarez. History of study Bonaparte (1991) described the first alvarezsaurid, ''Alvarezsaurus calvoi'', from an incomplete skeleton found in Patagonia, Argentina. Bonaparte also named a family, Alvarezsauridae, to contain it. He a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alvarezsauridae
Alvarezsauridae is a family of small, long-legged dinosaurs. Although originally thought to represent the earliest known flightless birds, they are now thought to be an early diverging branch of maniraptoran theropods. Alvarezsaurids were highly specialized. They had tiny but stout forelimbs, with compact, bird-like hands. Their skeletons suggest that they had massive breast and arm muscles, possibly adapted for digging or tearing. They had long, tube-shaped snouts filled with tiny teeth. They have been interpreted as myrmecophagous, adapted to prey on colonial insects such as termites, with the short arms acting as effective digging instruments to break into nests. ''Alvarezsaurus'', the type genus of the family, was named for the historian Gregorio Álvarez. History of study Bonaparte (1991) described the first alvarezsaurid, ''Alvarezsaurus calvoi'', from an incomplete skeleton found in Patagonia, Argentina. Bonaparte also named a family, Alvarezsauridae, to contain it. He a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alvarezsauroidea
Alvarezsauroidea is a group of small maniraptoran dinosaurs. Alvarezsauroidea, Alvarezsauridae, and Alvarezsauria are named for the historian Gregorio Álvarez, not the more familiar physicist Luis Alvarez, or his son geologist Walter Alvarez who jointly proposed that the Cretaceous–Paleogene extinction event was caused by an impact event. The group was first formally proposed by Choiniere and colleagues in 2010, to contain the family Alvarezsauridae and non-alvarezsaurid alvarezsauroids, such as ''Haplocheirus'',Choiniere, J.N., Xu, X., Clark, J.M., Forster, C.A., Guo, Y. and Han, F. (2010). "A basal alvarezsauroid theropod from the early Late Jurassic of Xinjiang, China." ''Science'', 327: 571-574. which is the basalmost of the Alvarezsauroidea (from the Late Jurassic, Asia). The discovery of ''Haplocheirus'' extended the stratigraphic evidence for the group Alvarezsauroidea about 63 million years further in the past. The division of Alvarezsauroidea into the Alvarezsau ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parvicursor
''Parvicursor'' (meaning "small runner") is a genus of tiny maniraptoran dinosaur with long slender legs for fast running. At only about from snout to end of tail, and in weight, it was initially seen as one of the smallest non-avian dinosaurs known from an adult specimen.Which was the smallest dinosaur? Royal Tyrrell Museum. Last accessed 2008-05-23. However, in 2022 its was concluded to represent a juvenile individual. Like other members of the |
Wulansuhai Formation
The Bayan Mandahu Formation (also known as Wulansuhai Formation or Wuliangsuhai Formation) is a geological unit of "redbeds" located near the village of Bayan Mandahu in Inner Mongolia, China Asia (Gobi Desert) and dates from the late Cretaceous Period. Laid down in the Campanian, it is dated somewhat uncertainly to between 75 and 71 mya (million years ago). Description The paleoenvironment it preserves was semi-arid and characterized by alluvial (stream-deposited) and eolian (wind-deposited) sediments. The formation is known for its vertebrate fossils, most of which are preserved in unstructured sandstone, indicating burial by wind-blown sandstorms. Paleofauna of the Bayan Mandahu Formation The fauna of the Bayan Mandahu is very similar in composition to the nearby Djadochta Formation, and the two may have been deposited at roughly the same time. These two formations share many of the same genera, but differ in the makeup of species. For example, the most common mammal in th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alnashetri Cerropoliciensis
''Alnashetri'' is an extinct genus of alvarezsaurid coelurosaurian theropod dinosaur known from the early Late Cretaceous (Cenomanian stage) of La Buitrera, Río Negro Province, Argentina. It contains one known species, ''Alnashetri cerropoliciensis''. Its remains were discovered in Candeleros Formation. Discovery ''Alnashetri'' is known only from the holotype MPCA-477, articulated hind limbs of a single individual. The holotype consists of a partial left femur, distal portions of left and right tibiae, right fibula, proximal tarsals of both ankles, a nearly complete right metatarsus, proximal and distal parts of the left metapodials and left pedal digit III. The specimen was collected at the "Hoyada de los esfenodontes" sublocality, part of the main fossiliferous locality of La Buitrera, about 30 km south of the village of El Chocόn in 2005. It was recovered from massive red sandstones that form the upper part of the Candeleros Formation of the Rio Limay Subgroup (Ceno ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Basal (phylogenetics)
In phylogenetics, basal is the direction of the ''base'' (or root) of a phylogenetic tree#Rooted tree, rooted phylogenetic tree or cladogram. The term may be more strictly applied only to nodes adjacent to the root, or more loosely applied to nodes regarded as being close to the root. Note that extant taxa that lie on branches connecting directly to the root are not more closely related to the root than any other extant taxa. While there must always be two or more equally "basal" clades sprouting from the root of every cladogram, those clades may differ widely in taxonomic rank, Phylogenetic diversity, species diversity, or both. If ''C'' is a basal clade within ''D'' that has the lowest rank of all basal clades within ''D'', ''C'' may be described as ''the'' basal taxon of that rank within ''D''. The concept of a 'key innovation' implies some degree of correlation between evolutionary innovation and cladogenesis, diversification. However, such a correlation does not make a given ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dinosaur
Dinosaurs are a diverse group of reptiles of the clade Dinosauria. They first appeared during the Triassic period, between 243 and 233.23 million years ago (mya), although the exact origin and timing of the evolution of dinosaurs is the subject of active research. They became the dominant terrestrial vertebrates after the Triassic–Jurassic extinction event 201.3 mya; their dominance continued throughout the Jurassic and Cretaceous periods. The fossil record shows that birds are feathered dinosaurs, having evolved from earlier theropods during the Late Jurassic epoch, and are the only dinosaur lineage known to have survived the Cretaceous–Paleogene extinction event approximately 66 mya. Dinosaurs can therefore be divided into avian dinosaurs—birds—and the extinct non-avian dinosaurs, which are all dinosaurs other than birds. Dinosaurs are varied from taxonomic, morphological and ecological standpoints. Birds, at over 10,700 living species, are among ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alvarezsaurus Calvoi
''Alvarezsaurus'' (; "Alvarez's lizard") is a genus of alvarezsaurid dinosaur from the Late Cretaceous, living in Argentina approximately 86 - 83 million years ago. It was a small dinosaur, measuring long and weighing approximately . It was found in the Bajo de la Carpa Formation and was named by paleontologist José Bonaparte in 1991 after the historian Don Gregorio Alvarez. The type species is ''A. calvoi''. Description ''Alvarezsaurus'' was a bipedal theropod. Like other lightweight theropods, it had a long tail, and its leg structure suggests that it was a fast runner. The most proximal elements of ''Alvarezsaurus'' caudal vertebrae exhibited ventrally sharp centra and the transerve processes of these vertebrae were sub-triangular and laterodistally directed, features seen in other alvarezsaurids like ''Shuvuuia''. Spinal processes were entirely absent or poorly developed, and each caudal vertebra supported short prezygapophyses. The scapula was visibly curved and proporti ... [...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 ance ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
