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Dinosauriformes
Dinosauromorpha is a clade of avemetatarsalian archosaurs (reptiles closer to birds than to crocodilians) that includes the Dinosauria (dinosaurs) and some of their close relatives. It was originally defined to include dinosauriforms and lagerpetids, with later formulations specifically excluding pterosaurs from the group. Birds are the only dinosauromorphs which survive to the present day. Classification The name "Dinosauromorpha" was briefly coined by Michael J. Benton in 1985. It was considered an alternative name for the group "Ornithosuchia", which was named by Jacques Gauthier to correspond to archosaurs closer to dinosaurs than to crocodilians. Although "Ornithosuchia" was later recognized as a misnomer (since ornithosuchids are now considered closer to crocodilians than to dinosaurs), it was still a more popular term than Dinosauromorpha in the 1980s. The group encompassed by Gauthier's "Ornithosuchia" and Benton's "Dinosauromorpha" is now given the name Avemetatar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dinosauriformes
Dinosauromorpha is a clade of avemetatarsalian archosaurs (reptiles closer to birds than to crocodilians) that includes the Dinosauria (dinosaurs) and some of their close relatives. It was originally defined to include dinosauriforms and lagerpetids, with later formulations specifically excluding pterosaurs from the group. Birds are the only dinosauromorphs which survive to the present day. Classification The name "Dinosauromorpha" was briefly coined by Michael J. Benton in 1985. It was considered an alternative name for the group "Ornithosuchia", which was named by Jacques Gauthier to correspond to archosaurs closer to dinosaurs than to crocodilians. Although "Ornithosuchia" was later recognized as a misnomer (since ornithosuchids are now considered closer to crocodilians than to dinosaurs), it was still a more popular term than Dinosauromorpha in the 1980s. The group encompassed by Gauthier's "Ornithosuchia" and Benton's "Dinosauromorpha" is now given the name Avemetatar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Marasuchus
''Marasuchus'' (meaning " Mara crocodile") is a genus of basal dinosauriform archosaur which is possibly synonymous with ''Lagosuchus''. Both genera lived during the Late Triassic in what is now La Rioja Province, Argentina. ''Marasuchus'' contains a single species, ''Marasuchus lilloensis''. ''Marasuchus lilloensis'' was originally designated as ''Lagosuchus lilloensis'' in 1972. It was considered a new species of ''Lagosuchus'', a contemporary archosaur described the previous year. However, a 1994 study argued that the original material of ''Lagosuchus'' was undiagnostic. This would mean that ''Lagosuchus'' and its original species (''Lagosuchus talampayaensis)'' could be considered nomen dubia. Specimens of ''Lagosuchus'' stored at a museum in San Miguel de Tucuman were considered to be more diagnostic than those of ''L. talampayensis'', and thus they were given a new genus: ''Marasuchus''. A 2019 study redescribed the original material of ''Lagosuchus'' and concluded that ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Marasuchus Hip Photo
''Marasuchus'' (meaning " Mara crocodile") is a genus of basal dinosauriform archosaur which is possibly synonymous with ''Lagosuchus''. Both genera lived during the Late Triassic in what is now La Rioja Province, Argentina. ''Marasuchus'' contains a single species, ''Marasuchus lilloensis''. ''Marasuchus lilloensis'' was originally designated as ''Lagosuchus lilloensis'' in 1972. It was considered a new species of ''Lagosuchus'', a contemporary archosaur described the previous year. However, a 1994 study argued that the original material of ''Lagosuchus'' was undiagnostic. This would mean that ''Lagosuchus'' and its original species (''Lagosuchus talampayaensis)'' could be considered nomen dubia. Specimens of ''Lagosuchus'' stored at a museum in San Miguel de Tucuman were considered to be more diagnostic than those of ''L. talampayensis'', and thus they were given a new genus: ''Marasuchus''. A 2019 study redescribed the original material of ''Lagosuchus'' and concluded that ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nyasasaurus
''Nyasasaurus'' (meaning " Lake Nyasa lizard") is an extinct genus of avemetatarsalian archosaur from the putatively Middle Triassic Manda Formation of Tanzania that may be the earliest known dinosaur. The type species ''Nyasasaurus parringtoni'' was first described in 1956 in the doctoral thesis of English paleontologist Alan J. Charig, but it was not formally described until 2013. Previously, the oldest record of dinosaurs was from Brazil and Argentina and dated back to the mid-late Carnian stage, about 233.23 to 231.4 million years ago. ''Nyasasaurus'' comes from a deposit formerly considered Anisian in age, meaning that it would predate other early dinosaurs by about 12 million years. However, more recent studies cast doubt to this age, pointing out that the deposits would actually be Carnian in age, which would considerably reduce this temporal gap. History of study In the 1930s, the holotype of ''Nyasasaurus'' was collected in Parrington's locality B36 from the Lifua Memb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Asilisaurus
''Asilisaurus'' ( ); from Swahili, ''asili'' ("ancestor" or "foundation"), and Greek, (, "lizard") is an extinct genus of silesaurid archosaur. The type species is ''Asilisaurus kongwe.'' ''Asilisaurus'' fossils were uncovered in the Manda Beds of Tanzania and date back to the middle Ladinian-early Carnian, making it one of the oldest known members of the Avemetatarsalia (animals on the dinosaur/pterosaur side of the archosaurian family tree). It was the first non-dinosaurian dinosauriform recovered from Africa. The discovery of ''Asilisaurus'' has provided evidence for a rapid diversification of avemetatarsalians during the Middle Triassic, with the diversification of archosaurs during this time previously only documented in pseudosuchians ( crocodylian-line archosaurs). ''Asilisaurus'' is known from a relatively large amount of fossils compared to most non-dinosaur dinosauromorphs. This has allowed it to provide important information for the evolution of other silesaurids an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pisanosaurus
''Pisanosaurus'' () is an extinct genus of early dinosauriform, likely an ornithischian or silesaurid, from the Late Triassic of Argentina. It was a small, lightly built, ground-dwelling herbivore, that could grow up to an estimated long. Only one species, the type, ''Pisanosaurus mertii'', is known, based on a single partial skeleton discovered in the Ischigualasto Formation of the Ischigualasto-Villa Unión Basin in northwestern Argentina. This part of the formation has been dated to the late Carnian, approximately 229 million years ago. Discovery and naming ''Pisanosaurus'' is known from a single fragmented skeleton discovered in 1962 by Galileo Juan Scaglia at the Hoyada del Cerro Las Lajas locality (also known as Agua de Las Catas) in the Ischigualasto Formation of La Rioja Province, Argentina. The genus is based on a specimen given the designation PVL 2577, which consists of a partial skull including a fragmentary right maxilla with teeth, and incomplete right ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Archosaur
Archosauria () is a clade of diapsids, with birds and crocodilians as the only living representatives. Archosaurs are broadly classified as reptiles, in the cladistic sense of the term which includes birds. Extinct archosaurs include non-avian dinosaurs, pterosaurs, and extinct relatives of crocodilians. Modern paleontologists define Archosauria as a crown group that includes the most recent common ancestor of living birds and crocodilians, and all of its descendants. The base of Archosauria splits into two clades: Pseudosuchia, which includes crocodilians and their extinct relatives, and Avemetatarsalia, which includes birds and their extinct relatives (such as non-avian dinosaurs and pterosaurs). Older definitions of the group Archosauria rely on shared morphological characteristics, such as an antorbital fenestra in the skull, serrated teeth, and an upright stance. Some extinct reptiles, such as proterosuchids and euparkeriids, possessed these features yet originated pri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lagosuchus
''Lagosuchus'' is an extinct genus of avemetatarsalian archosaur from the Late Triassic of Argentina. The type species of ''Lagosuchus'', ''Lagosuchus talampayensis,'' is based on a small partial skeleton recovered from the early Carnian-age Chañares Formation. The holotype skeleton of ''L. talampayensis'' is fairly fragmentary, but it does possess some traits suggesting that ''Lagosuchus'' was a probable dinosauriform, closely related to dinosaurs. A second potential species of ''Lagosuchus'', ''L. lilloensis'', is based on an assortment of slightly larger and more well-preserved fossils. These larger specimens have been considered much more diagnostic and informative than the original small ''L. talampayensis'' skeleton. As a result, some paleontologists have placed the larger specimens into a new genus, ''Marasuchus''. ''Marasuchus'' is generally considered one of the more complete early dinosauriforms, useful for estimating ancestral traits for the origin of dinosaurs. This ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Agnosphitys
''Agnosphitys'' (; "unknown begetter"; sometimes mistakenly called ''Agnostiphys'' or ''Agnosphytis'') is a genus of dinosauriform that lived during the Late Triassic. It contains only one species, the type species ''A. cromhallensis''. Its remains include an ilium, maxilla, astragalus and humerus, which date variously from the Norian and Rhaetian stages of the Late Triassic, or possibly as late as the Hettangian stage of the Early Jurassic. The fissure fill at Avon, of which ''Agnosphitys'' was probably recovered from, was a sinkhole formed by the dissolution of Lower Carboniferous limestones. Discovery and naming The type species, ''Agnosphitys cromhallensis'', was described by Nicholas Fraser, Kevin Padian, Gordon Walkden and A. L. M Davis in early 2002. The fossils consist of two specimens. The holotype consists of a single isolated left ilium, while the second specimen consists of a partial skeleton including a left maxilla, a humerus and a left astragalus, were found in t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Avemetatarsalia
Avemetatarsalia (meaning "bird metatarsals") is a clade of diapsid reptiles containing all archosaurs more closely related to birds than to crocodilians. The two most successful groups of avemetatarsalians were the dinosaurs and pterosaurs. Dinosaurs were the largest terrestrial animals for much of the Mesozoic Era, and one group of small feathered dinosaurs (Aves, i.e. birds) has survived up to the present day. Pterosaurs were the first flying vertebrates and persisted through the Mesozoic before dying out at the Cretaceous-Paleogene (K-Pg) extinction event. Both dinosaurs and pterosaurs appeared in the Triassic Period, shortly after avemetatarsalians as a whole. The name Avemetatarsalia was first established by British palaeontologist Michael Benton in 1999. An alternate name is Panaves, or "all birds", in reference to its definition containing all animals, living or extinct, which are more closely related to birds than to crocodilians. Although dinosaurs and pterosaurs were th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Herrerasauridae
Herrerasauridae is a family of carnivorous dinosaurs, possibly basal to either theropods or even all of saurischians, or even their own branching from dracohors, separate from dinosauria altogether. They are among the oldest known dinosaurs, first appearing in the fossil record around 233.23 million years ago (the Carnian stage of the Late Triassic), before becoming extinct by the end of the Carnian stage. Herrerasaurids were relatively small-sized dinosaurs, normally no more than long, although the holotype specimen of "''Frenguellisaurus ischigualastensis"'' (nowadays considered a synonym of ''Herrerasaurus'' ''ischigualastensis'') is thought to have reached around 6 meters (20 ft) long. The best known representatives of this group are from South America (Brazil, Argentina), where they were first discovered in the 1930s in relation to ''Staurikosaurus'' and 1960s in relation to ''Herrerasaurus''. A nearly complete skeleton of ''Herrerasaurus ischigualastensis'' was discovered ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Silesauridae
Silesauridae is an extinct family of Triassic dinosauriforms. It is most commonly considered to be a clade of non-dinosaur dinosauriforms, and the sister group of dinosaurs. Some studies have instead suggested that most or all silesaurids comprised an early diverging clade or a paraphyletic grade within ornithischian dinosaurs. Silesaurids have a consistent general body plan, with a fairly long neck and legs and possibly quadrupedal habits, but most silesaurids are heavily fragmentary nonetheless. Furthermore, they occupied a variety of ecological niches, with early silesaurids (such as '' Lewisuchus'') being carnivorous and later taxa (such as ''Kwanasaurus'') having adaptations for specialized herbivory. As indicated by the contents of referred coprolites, '' Silesaurus'' may have been insectivorous, feeding selectively on small beetles and other arthropods. Classification Silesauridae is typically considered the sister group to Dinosauria. The group was named in 2010 by Ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
