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Megaraptor Namunhuaiquii
''Megaraptor'' () is a genus of large theropod dinosaur that lived in the ages of the Late Cretaceous. Its fossils have been discovered in the Patagonian Portezuelo Formation of Argentina, South America. Initially thought to have been a giant dromaeosaur-like coelurosaur, it was classified as a neovenatorid allosauroid in previous phylogenies, but more recent phylogeny and discoveries of related megaraptoran genera has placed it as either a basal tyrannosauroid or a basal coelurosaur with some studies still considering it a neovenatorid. Description ''Megaraptor'' was initially described as a giant dromaeosaur, known primarily from a single claw (about 30 cm long) that resembled the sickle-shaped foot claw of dromaeosaurids. The discovery of a complete front limb, however, showed that this giant claw actually came from the first finger of the hand. In 2010, Gregory S. Paul estimated its length at , its weight at . The hands were unusually elongated, bearing sickle-shaped ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Late Cretaceous
The Late Cretaceous (100.5–66 Ma) is the younger of two epochs into which the Cretaceous Period is divided in the geologic time scale. Rock strata from this epoch form the Upper Cretaceous Series. The Cretaceous is named after ''creta'', the Latin word for the white limestone known as chalk. The chalk of northern France and the white cliffs of south-eastern England date from the Cretaceous Period. Climate During the Late Cretaceous, the climate was warmer than present, although throughout the period a cooling trend is evident. The tropics became restricted to equatorial regions and northern latitudes experienced markedly more seasonal climatic conditions. Geography Due to plate tectonics, the Americas were gradually moving westward, causing the Atlantic Ocean to expand. The Western Interior Seaway divided North America into eastern and western halves; Appalachia and Laramidia. India maintained a northward course towards Asia. In the Southern Hemisphere, Australia and Ant ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dromaeosauridae
Dromaeosauridae () is a family of feathered theropod dinosaurs. They were generally small to medium-sized feathered carnivores that flourished in the Cretaceous Period. The name Dromaeosauridae means 'running lizards', from Greek ('), meaning 'runner', and ('), meaning 'lizard'. In informal usage, they are often called raptors (after ''Velociraptor''), a term popularized by the film '' Jurassic Park''; a few types include the term "raptor" directly in their name and have come to emphasize their bird-like appearance and speculated bird-like behavior. Dromaeosaurid fossils have been found across the globe in North America, Europe, Africa, Asia, South America and Antarctica, with some fossils giving credence to the possibility that they inhabited Australia as well. They first appeared in the mid-Jurassic Period (late Bathonian stage, about 167 million years ago) and survived until the end of the Cretaceous (Maastrichtian stage, 66 ma), existing until the Cretaceous–Paleogene ex ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phuwiangvenator
''Phuwiangvenator'' ("hunter of Phu Wiang") is a genus of 6 meter long megaraptoran theropod that lived during the Early Cretaceous period in what is now Thailand. It contains a single species, ''P. yaemniyomi'', recovered from the Sao Khua Formation. The holotype A holotype is a single physical example (or illustration) of an organism, known to have been used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of several ... was first found in 1993, before being named in 2019. The holotype specimen consists of a partial skeleton consisting of a dorsal vertebra, three fused sacral vertebrae, right metacarpal II, right manual phalanges and unguals, right and left tibiae, left astragalocalcaneum, left metatarsal I, right metatarsals II–IV, right pedal phalanges and unguals, with a referred specimen including an atlantal intercentrum and right astragalocalcaneum which were found together. In t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phylogenetic Analyses
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] |
Megaraptora
Megaraptora is a clade of carnivorous Tetanurae, tetanuran theropod dinosaurs with controversial relations to other theropods. Its Derived (phylogenetics), derived members, the Megaraptoridae are noted for their elongated hand claws and proportionally large arms, which are usually reduced in size in other large theropods. Megaraptorans are incompletely known, and no complete megaraptoran skeleton has been found. However, they still possessed a number of unique features. Their forelimbs were large and strongly built, and the Glossary of dinosaur anatomy#ulna, ulna bone had a unique shape in members of the Family (biology), family Megaraptoridae, a subset of megaraptorans which excludes ''Fukuiraptor'' and ''Phuwiangvenator''. The first two fingers were elongated, with massive curved claws, while the third finger was small. Megaraptoran skull material is very incomplete, but a juvenile ''Megaraptor'' described in 2014 preserved a portion of the snout, which was long and slender. Le ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fukuiraptor
''Fukuiraptor'' ("thief of Fukui") was a medium-sized megaraptoran theropod dinosaur of the Early Cretaceous epoch (either Barremian or Aptian) that lived in what is now Japan. ''Fukuiraptor'' is known from the Kitadani Formation and possibly also the Sebayashi Formation. Description and history The type specimen is a partial skeleton (designated FPDM-V97122) discovered in the Kitadani quarry near Katsuyama in the Fukui prefecture. It is thought that this specimen was not mature and an adult may have been larger. The remains of many other individuals have been found in the quarry, with numerous humeri, femurs, and teeth being assigned to this species. However, the other individuals recovered from the same locality are mostly juveniles that were smaller than the holotype (Currie & Azuma, 2006), in the smallest case less than a quarter of the holotype's size. A tooth (NDC-P0001) discovered in a block of conglomerate from the Sebayashi Formation has been referred to ''F ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Maip
''Maip'' is a genus of large megaraptorid theropod dinosaur from the Late Cretaceous (Maastrichtian) Chorrillo Formation of Santa Cruz, Argentina. The genus contains a single species, ''M. macrothorax'', known from an incomplete, disarticulated skeleton. ''Maip'' may represent the largest megaraptorid known from South America, and possibly the world. Discovery and naming The ''Maip'' holotype specimen, MPM 21545, was discovered by Alexis Rolando on the La Anita Farm, west of El Calafate, Santa Cruz province, Argentina, in 2019. The specimen was found disarticulated but in association over an area of . The known fossil material consists of the axis, several dorsal and caudal vertebrae, cervical and dorsal ribs, gastralia, a left coracoid, fragmentary scapula, partial right pubis, and partial metatarsal. Some of these bones were described in 2019 by Novas ''et al''. The holotype specimen includes some bones previously unknown in other megaraptorids. Although fragmentary, it r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chilantaisaurus
''Chilantaisaurus'' (" lizard") is a genus of large theropod dinosaur, possibly a neovenatorid or a primitive coelurosaur, from the Late Cretaceous Ulansuhai Formation of China (Turonian age, about 92 million years ago). The type species, ''C. tashuikouensis'', was described by Hu in 1964. Description ''Chilantaisaurus'' was a large theropod, estimated as weighing between and . In 2010, Brusatte et al. estimated it to weigh , based on femur length measurements. However, considering that greater femoral circumference indicates the greater capacity to withstand greater locomotor loads (not greater body mass), the 2020 study moderated the body mass of the holotype at . It is estimated to be around to long. Classification Hu considered ''Chilantaisaurus'' to be a carnosaur related to ''Allosaurus'', though some subsequent studies suggested that it may be a spinosauroid, possibly a primitive member of the spinosaurid family (Sereno, 1998; Chure, 2000; Rauhut, 2001) because it ha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Baryonyx
''Baryonyx'' () is a genus of theropod dinosaur which lived in the Barremian stage of the Early Cretaceous period, about 130–125 million years ago. The first skeleton was discovered in 1983 in the Smokejack Clay Pit, of Surrey, England, in sediments of the Weald Clay Formation, and became the holotype specimen of ''Baryonyx walkeri'', named by palaeontologists Alan J. Charig and Angela C. Milner in 1986. The generic name, ''Baryonyx'', means "heavy claw" and alludes to the animal's very large claw on the first finger; the specific name, ''walkeri'', refers to its discoverer, amateur fossil collector William J. Walker. The holotype specimen is one of the most complete theropod skeletons from the UK (and remains the most complete Spinosaurid), and its discovery attracted media attention. Specimens later discovered in other parts of the United Kingdom and Iberia have also been assigned to the genus, though many have since been moved to new genera. The holotype specimen, whic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gualicho
''Gualicho'' (named in reference to the gualichu) is a genus of theropod dinosaur. The type species is ''Gualicho shinyae''. It lived in what is now northern Patagonia, on what was then a South American island continent split off from the supercontinent Gondwana. The fossils were found in the Huincul Formation, dating to the late Cenomanian-early Turonian age of the upper Cretaceous Period, around 91 million years ago. Discovery On 13 February 2007, Akiko Shinya, preparator of the Field Museum of Natural History, east of the Ezequiel Ramos Mexía Reservoir at the Rancho Violante, discovered the skeleton of a theropod new to science. In 2016, the specimen was named and described by Sebastián Apesteguía, Nathan D. Smith, Rubén Juárez Valieri and Peter J. Makovicky. The generic name is derived from the ''gualichu'', a demon of local folklore. The specific name honours Shinya as the animal's discoverer. The holotype, MPCN PV 0001, consists of a partial skeleton lacking the sk ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Megalosauroidea
Megalosauroidea (meaning 'great/big lizard forms') is a superfamily (or clade) of tetanuran theropod dinosaurs that lived from the Middle Jurassic to the Late Cretaceous period. The group is defined as ''Megalosaurus bucklandii'' and all taxa sharing a more recent common ancestor with it than with ''Allosaurus fragilis'' or ''Passer domesticus''. Members of the group include ''Spinosaurus'', ''Megalosaurus'', and ''Torvosaurus''. They are possibly paraphyletic in nature. Classification The name Spinosauroidea is sometimes used in place of Megalosauroidea. The superfamily Spinosauroidea was named in 1915 by Ernst Stromer. It is a synonym of Megalosauroidea in almost all modern phylogenetic analyses, and it is therefore redundant. Spinosauroidea was defined as a clade in 1998 by Paul Sereno as the node clade containing the common ancestor of ''Spinosaurus'' and ''Torvosaurus'' and all its descendants. Thomas Holtz in 2004 defined a branch clade with the same name containing all spec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ameghiniana
''Ameghiniana'' is a peer-reviewed scientific journal covering palaeontology published by the Asociación Paleontológica Argentina. It is named after the 19th century Italian Argentine palaeontologist Florentino Ameghino. The discovery of many dinosaurs found in Argentina and South America have first been published in ''Ameghiniana''; examples of this are ''Argentinosaurus'' and ''Herrerasaurus ''Herrerasaurus'' is a genus of saurischian dinosaur from the Late Triassic period. This genus was one of the earliest dinosaurs from the fossil record. Its name means "Herrera's lizard", after the rancher who discovered the first specimen in ...''. Abstracting and indexing The journal is abstracted and indexed in: References External links * Asociación Paleontológica Argentina Paleontology journals Geology of Argentina Publications established in 1957 Multilingual journals Quarterly journals Academic journals published by learned and professional societies of Arge ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
