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Thanos Simonattoi
''Thanos'' (named for the Marvel Comics character) is a genus of carnivorous brachyrostran abelisaurid dinosaur that lived in Brazil during the Santonian stage of the late Cretaceous Period. It contains only a single species known as ''T. simonattoi''. Discovery and naming In 2014, it was reported in the scientific literature that Sérgio Luis Simonatto with a team of the ''Museu de Paleontologia "Prof. Antonio Celso de Arruda Campos"'' had found the front of a theropod axis near São José do Rio Preto. Several years later Fabiano Vidoi Iori uncovered the rear part of the same vertebra. In 2018, the type species ''Thanos simonattoi'' was named and described by Rafael Delcourt and Fabiano Vidoi Iori in an advance online publication in the journal ''Historical Biology''. The paper was later published in print in 2020, making it the official year of description. The generic name refers to the Marvel Comics character Thanos, invented by Jim Starlin; Thanos was the main antagonist ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Santonian
The Santonian is an age in the geologic timescale or a chronostratigraphic stage. It is a subdivision of the Late Cretaceous Epoch or Upper Cretaceous Series. It spans the time between 86.3 ± 0.7 mya (million years ago) and 83.6 ± 0.7 mya. The Santonian is preceded by the Coniacian and is followed by the Campanian.Gradstein ''et al.'' (2004) Stratigraphic definition The Santonian Stage was established by French geologist Henri Coquand in 1857. It is named after the city of Saintes in the region of Saintonge, where the original type locality is located. The base of the Santonian Stage is defined by the appearance of the inoceramid bivalve ''Cladoceramus undulatoplicatus''. The GSSP (official reference profile) for the base of the Santonian Stage is located near Olazagutia, Spain; it was ratified by the Subcommission on Cretaceous Stratigraphy in 2012. The Santonian's top (the base of the Campanian Stage) is informally marked by the extinction of the crinoid '' Marsupites tes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Maastrichtian
The Maastrichtian () is, in the ICS geologic timescale, the latest age (uppermost stage) of the Late Cretaceous Epoch or Upper Cretaceous Series, the Cretaceous Period or System, and of the Mesozoic Era or Erathem. It spanned the interval from . The Maastrichtian was preceded by the Campanian and succeeded by the Danian (part of the Paleogene and Paleocene). The Cretaceous–Paleogene extinction event (formerly known as the Cretaceous–Tertiary extinction event) occurred at the end of this age. In this mass extinction, many commonly recognized groups such as non-avian dinosaurs, plesiosaurs and mosasaurs, as well as many other lesser-known groups, died out. The cause of the extinction is most commonly linked to an asteroid about wide colliding with Earth, ending the Cretaceous. Stratigraphic definitions Definition The Maastrichtian was introduced into scientific literature by Belgian geologist André Hubert Dumont in 1849, after studying rock strata of the Chalk Group c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Indosaurus
''Indosaurus'' () is a genus of carnivorous theropod dinosaur that lived in what is now India, about 69 to 66 million years ago during the Maastrichtian division of the Late Cretaceous. The species I. matleyi weighed roughly 700 kg (1540 lb). History The type species, ''Indosaurus matleyi'', was named by Huene and Matley in 1933 making Indosaurus the first Majungasaurine to be discovered.F. von Huene and C. A. Matley, 1933, "The Cretaceous Saurischia and Ornithischia of the Central Provinces of India", ''Palaeontologica Indica (New Series), Memoirs of the Geological Survey of India'' 21(1): 1-74 The generic name refers to India and the specific name honours Matley. This species now also includes ''Megalosaurus matleyi''; confusingly, the dubious tooth taxon ''Orthogoniosaurus'' shares the same specific name but is based on different material. Some paleontologists have speculated that ''Indosuchus'' and ''Compsosuchus'' should also be included within the genus ''Ind ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rajasaurus
''Rajasaurus'' (meaning "princely lizard") is a genus of carnivorous abelisaurid theropod dinosaur from the Late Cretaceous of India, containing one species: ''Rajasaurus narmadensis''. The bones were excavated from the Lameta Formation in the Gujarat state of Western India, probably inhabiting what is now the Narmada River Valley. It was formally described by palaeontologist Jeffrey A. Wilson and colleagues in 2003 based on a partial skeleton comprising the braincase, spine, hip bone, legs, and tail–a first for an Indian theropod. The dinosaur likely measured , and had a single horn on the forehead which was probably used for display and head-butting. Like other abelisaurids, ''Rajasaurus'' was probably an ambush predator. India at this time was an island, due to the break-up of the supercontinent Gondwana, though it is possible animals still were able to migrate to and from nearby continents. The creation of the subfamily Majungasaurinae, and its inclusion of abelisaurid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Majungasaurinae
Majungasaurinae (after ''Majungasaurus'', itself named after the city of Mahajanga in Madagascar) is a subfamily of large carnivorous theropods from the Upper Cretaceous, found in Madagascar, India, and France. It is a subgroup within the theropod family Abelisauridae, a Gondwanan clade known for their thick and often horned skulls and vestigial arms. The two subfamilies of Abelisauridae are Carnotaurinae, best known from the South American ''Carnotaurus'', and Majungasaurinae, consisting of Madagascar’s ''Majungasaurus'' and its closest relatives. Their ancestors emerged in the Middle Jurassic, and the clade lasted until the Upper Cretaceous. The majungasaurines were mid-sized, bipedal predators, but relatively slow moving. Their stout legs were built for striding, not running. They had tall, deep heads with powerful jaws, but small forearms without carpals in the wrists. Because of their slow gait and small arms, they likely preyed upon the larger, slower sauropods rather th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rugops
''Rugops'' (meaning ‘wrinkle face’) is a monospecific genus of basal abelisaurid theropod dinosaur from Niger that lived during the Late Cretaceous period (Cenomanian stage, ~95 Ma) in what is now the Echkar Formation. The type and only species, ''Rugops primus'', is known only from a partial skull. It was named and described in 2004 by Paul Sereno, Jeffery Wilson and Jack Conrad. ''Rugops'' has an estimated length of 4.4–5.3 metres (14.4–17.4 ft) and weight of 410 kilograms (900 lbs). The top of its skull bears several pits which correlates with overlaying scale and the front of the snout would have had an armour-like dermis. Discovery and naming A skull pertaining to an abelisaurid was recovered during an expedition in 2000 led by Paul Sereno near In-Abangharit, Niger Republic. The specimen came from the Echkar Formation of the Tegama Group which dates to the Cenomanian stage of the Late Cretaceous period, 96 Ma. The formation has also yielded specimens pertaining to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kryptops
''Kryptops'' is a genus of abelisaurid theropod dinosaur from the Early Cretaceous of Niger. It is known from a partial skeleton found at the Gadoufaoua locality in the western Ténéré Desert, in rocks of the Aptian-Albian age Elrhaz Formation. This dinosaur was described by paleontologists Paul Sereno and Stephen Brusatte in 2008. The genus name means "covered face", in reference to evidence that the face bore a tightly adhering covering. The type species is ''K. palaios,'' which means "old". Discovery The holotype skeleton, MNN GAD1, includes a maxilla (main tooth-bearing bone of the upper jaw), vertebrae, ribs, and articulated pelvic girdle and sacrum, belonging to an adult about . According to the describers, this specimen represents one of the earliest known abelisaurids, and is notable for the heavily textured surface of the maxilla; the presence of pits and impressions of blood vessels indicates that there was a covering firmly attached to the face, perhaps of kera ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chenanisaurus
''Chenanisaurus'' is a genus of predatory abelisaurid dinosaur, with a single known species ''C. barbaricus''. It comes from the upper Maastrichtian phosphates of the Ouled Abdoun Basin in Morocco, North Africa. The animal is known from a holotype, consisting of a partial jaw bone, and several isolated teeth found in the same beds. ''Chenanisaurus'' is one of the largest members of the Abelisauridae, and one of the last, being a contemporary of the North American ''Tyrannosaurus''. It would have been among the dinosaur species wiped out by the Chicxulub asteroid impact and the Cretaceous-Paleogene mass extinction that followed. Description ''Chenanisaurus'' is quite a large abelisaurid, measuring , based on measurements of the holotype dentary. Its size is comparable to that of large abelisaurids such as ''Carnotaurus'' and ''Pycnonemosaurus''. Nicholas R. Longrich and colleagues, the describers of ''Chenanisaurus'', identified distinctive features distinguishing the anim ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Abelisauridae
Abelisauridae (meaning "Abel's lizards") is a family (or clade) of ceratosaurian theropod dinosaurs. Abelisaurids thrived during the Cretaceous period, on the ancient southern supercontinent of Gondwana, and today their fossil remains are found on the modern continents of Africa and South America, as well as on the Indian subcontinent and the island of Madagascar. Isolated teeth were found in the Late Jurassic of Portugal, and the Late Cretaceous genera '' Tarascosaurus'' and ''Arcovenator'' have been described in France. Abelisaurids first appear in the fossil record of the early middle Jurassic period, and at least two genera (the Moroccan ''Chenanisaurus'' and the Madagascan ''Majungasaurus'') survived until the end of the Mesozoic era 66 million years ago. Like most theropods, abelisaurids were carnivorous bipeds. They were characterized by stocky hind limbs and extensive ornamentation of the skull bones, with grooves and pits. In many abelisaurids, such as ''Carnotaurus'', ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carnotaurinae
Carnotaurinae is a subfamily of the theropod dinosaur family Abelisauridae. It includes the dinosaurs ''Aucasaurus'' (from Argentina), ''Carnotaurus'' (from Argentina). The group was first proposed by American paleontologist Paul Sereno in 1998, defined as a clade containing all abelisaurids more closely related to ''Carnotaurus'' than to ''Majungasaurus''. Classification *Subfamily Carnotaurinae **Brachyrostra ***''Ekrixinatosaurus'' (Argentina) ***''Elemgasem'' (Argentina) ***''Guemesia'' (Argentina) ***''Ilokelesia'' (Argentina) ***''Skorpiovenator'' (Argentina) ***''Thanos'' (Brazil) *** Furileusauria ****?'' Niebla'' (Argentina) ****'' Llukalkan'' (Argentina) ****'' Viavenator'' (Argentina) ****''Pycnonemosaurus'' (Brazil) ****''Quilmesaurus'' (Argentina) ****Carnotaurini *****''Carnotaurus'' (Argentina) ***** Abelisaurinae ******''Aucasaurus'' (Argentina) ******'' Abelisaurus'' (Argentina) Phylogeny In 2008, Canale ''et al.'' published a phylogenetic analysis focusing on ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polytomy
An internal node of a phylogenetic tree is described as a polytomy or multifurcation if (i) it is in a rooted tree and is linked to three or more child subtrees or (ii) it is in an unrooted tree and is attached to four or more branches. A tree that contains any multifurcations can be described as a multifurcating tree. Soft polytomies vs. hard polytomies Two types of polytomies are recognised, soft and hard polytomies. Soft polytomies are the result of insufficient phylogenetic information: though the lineages diverged at different times – meaning that some of these lineages are closer relatives than others, and the available data does not allow recognition of this. Most polytomies are soft, meaning that they would be resolved into a typical tree of dichotomies if better data were available. In contrast, a hard polytomy represents a true divergence event of three or more lineages. Applications Interpretations for a polytomy depend on the individuals, that are represe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phylogenetic Analysis
In biology, phylogenetics (; from Greek φυλή/ φῦλον [] "tribe, clan, race", and wikt:γενετικός, γενετικός [] "origin, source, birth") is the study of the evolutionary history and relationships among or within groups of organisms. These relationships are determined by Computational phylogenetics, phylogenetic inference methods that focus on observed heritable traits, such as DNA sequences, protein amino acid sequences, or morphology. The result of such an analysis is a phylogenetic tree—a diagram containing a hypothesis of relationships that reflects the evolutionary history of a group of organisms. The tips of a phylogenetic tree can be living taxa or fossils, and represent the "end" or the present time in an evolutionary lineage. A phylogenetic diagram can be rooted or unrooted. A rooted tree diagram indicates the hypothetical common ancestor of the tree. An unrooted tree diagram (a network) makes no assumption about the ancestral line, and does n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
