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Pteranodontids
The Pteranodontidae are a family of large pterosaurs of the Cretaceous Period of North America and Africa. The family was named in 1876 by Othniel Charles Marsh. Pteranodontids had a distinctive, elongated crest jutting from the rear of the head (most famously seen in ''Pteranodon'' itself). The spectacularly-crested ''Nyctosaurus'' is sometimes included in this family, though usually placed in its own family, the Nyctosauridae (Nicholson & Lydekker, 1889). Modern researchers differ in their use of the concept. S. Christopher Bennett and Alexander Kellner have concluded that ''Nyctosaurus'' was not a pteranodontid. In 1994 Bennett defined a clade Pteranodontidae, also including species of the Anhangueridae. However, this definition has not been accepted by other workers. Alexander Kellner, for example, named several additional species for specimens previously classified as ''Pteranodon'', and placed ''P. sternbergi'' in a distinct genus, ''Geosternbergia''. Kellner re-defined Ptera ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nyctosaurus
''Nyctosaurus'' (meaning "night lizard" or "bat lizard") is a genus of nyctosaurid pterosaur from the Late Cretaceous period of what is now the Niobrara Formation of the mid-western United States, which, during the time ''Nyctosaurus'' was alive, was covered in an extensive shallow sea. Some remains belonging to a possible ''Nyctosaurus'' species called ''N.lamegoi'' have been found in Brazil, making ''Nyctosaurus'' more diverse. The genus ''Nyctosaurus'' has had numerous species referred to it, though how many of these may actually be valid requires further study. At least one species possessed an extraordinarily large antler-like cranial crest. ''Nyctosaurus'' was a mid-sized pterosaur that lived along the shores of the Niobrara Formation of the United States, which back then was within a large inland sea called the Western Interior Seaway. It has been suggested that it would have flown similar to modern-day soaring birds such as albatrosses, which consisted of flying very lon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pterosaur
Pterosaurs (; from Greek ''pteron'' and ''sauros'', meaning "wing lizard") is an extinct clade of flying reptiles in the order, Pterosauria. They existed during most of the Mesozoic: from the Late Triassic to the end of the Cretaceous (228 to 66 million years ago). Pterosaurs are the earliest vertebrates known to have evolved powered flight. Their wings were formed by a membrane of skin, muscle, and other tissues stretching from the ankles to a dramatically lengthened fourth finger. There were two major types of pterosaurs. Basal pterosaurs (also called 'non-pterodactyloid pterosaurs' or 'rhamphorhynchoids') were smaller animals with fully toothed jaws and, typically, long tails. Their wide wing membranes probably included and connected the hind legs. On the ground, they would have had an awkward sprawling posture, but the anatomy of their joints and strong claws would have made them effective climbers, and some may have even lived in trees. Basal pterosaurs were insectiv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dawndraco
''Dawndraco'' is a controversial genus of pteranodontid pterosaur from the Late Cretaceous of North America. It is likely synonymous with the contemporary pteranodontid ''Geosternbergia.'' ''Dawndraco'' was named by Alexander W.A. Kellner in 2010. The type species is ''Dawndraco kanzai''. The generic name combines the Dawn deity of the Iroquois with a Latin ''draco'', "dragon". The specific name refers to the Kanza tribe of Kansas. ''Dawndraco'' is based on the holotype specimen UALVP 24238, a partial skeleton including an almost complete skull and lower jaws. It was recovered in 1974 by Richard C. Fox and Allen Lindoe from rocks of the lower part of the Smoky Hill Chalk Member of the Niobrara Formation in Utica, Kansas. These rocks date to the late Coniacian or early Santonian stage, about 86 million years ago. The specimen was earlier referred to ''Pteranodon sternbergi''. However, when Kellner in 2010 assigned this latter species to the genus ''Geosternbergia'', he ... [...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] |
Pteranodon
''Pteranodon'' (); from Ancient Greek (''pteron'', "wing") and (''anodon'', "toothless") is a genus of pterosaur that included some of the largest known flying reptiles, with ''P. longiceps'' having a wingspan of . They lived during the late Cretaceous geological period of North America in present-day Kansas, Nebraska, Wyoming, South Dakota and Alabama. More fossil specimens of ''Pteranodon'' have been found than any other pterosaur, with about 1,200 specimens known to science, many of them well preserved with nearly complete skulls and articulated skeletons. It was an important part of the animal community in the Western Interior Seaway. ''Pteranodon'' was not a dinosaur. By definition, all dinosaurs belong to the group Dinosauria; ''Pteranodon'' belongs to the group Pterosauria. Nonetheless, ''Pteranodon'' is the most famous pterosaur, frequently featured in dinosaur media and strongly associated with dinosaurs by the general public. While not dinosaurs, pterosaurs such as ' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geosternbergia Sternbergi
''Geosternbergia'' is an extinct genus of pteranodontid pterodactyloid pterosaur from the Late Cretaceous geological period of North America. ''Geosternbergia'' was one of the largest pterosaur genera, and had a wingspan of up to . Discovery and history The first fossils of ''Geosternbergia'' were collected by American paleontologist George F. Sternberg in 1952 from the lower portion of the Niobrara Formation. The fossils of the animal looked similar to those of the species ''Pteranodon longiceps'', but the crests were set upright and in a slightly different position. In 1958, Sternberg and paleontologist Myrl V. Walker published a study about this peculiar find. In 1966, American paleontologist John Christian Harksen assigned the specimens found as a new species of ''Pteranodon'' called ''P. sternbergi'' due to its distinct upright crest that set it apart from ''P. longiceps''. Halsey W. Miller however, concluded a revision of the different species of ''Pteranodon'' in 19 ... [...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] |
Volgadraco
''Volgadraco'' ("Volga River dragon") is a genus of pterodactyloid pterosaur from the Upper Cretaceous of European Russia. ''Volgadraco'' was originally classified as an azhdarchid. However, recent studies have concluded that it may belong to either the family Nyctosauridae, or the family Pteranodontidae. ''Volgadraco'' is known from lower beak (holotype SGU, no. 46/104a) and postcranial fragments from the early Campanian-age Rybushka Formation of Saratov, Russia. The size of this animal, and the development of blood supply in the lower jaw are intermediate between older Santonian or Turonian azhdarchids like ''Azhdarcho'' and '' Bakonydraco'' and later Maastrichtian azhdarchids like '' Quetzalcoatlus''. ''Volgadraco'' was described in 2008 by Averianov, Arkhangelsky, and Pervushov. The type species is ''V. bogolubovi'', the specific name honouring Russian paleontologist Nikolai Nikolaevich Bogolubov. The authors consider the earlier named genus ''Bogolubovia'' to be a '' no ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tethydraco
''Tethydraco'' is a genus of pterodactyloid pterosaur that lived during the Late Cretaceous period (Maastrichtian stage) of what is now the area of present Morocco, about 66 million years ago. ''Tethydraco'' was originally assigned to the family Pteranodontidae. Subsequently described material suggested that it was an azhdarchid, and possibly synonymous with ''Phosphatodraco''. The type and only species is ''T. regalis''. Discovery and naming Since 2015, a group of paleontologists has been acquiring pterosaur fossils from commercial Moroccan fossil traders, who obtain these from workers in the phosphate mines on the Khouribga plateau, which is located within the Ouled Abdoun Basin. The purpose of this project is to determine pterosaur diversity in the latest Cretaceous. From this stage, no Konservat-Lagerstätten are known, sites combining a large variety of species with exceptional preservation. It is in such sites that the vast majority of pterosaur fossils and taxa have bee ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geosternbergia
''Geosternbergia'' is an extinct genus of pteranodontid pterodactyloid pterosaur from the Late Cretaceous geological period of North America. ''Geosternbergia'' was one of the largest pterosaur genera, and had a wingspan of up to . Discovery and history The first fossils of ''Geosternbergia'' were collected by American paleontologist George F. Sternberg in 1952 from the lower portion of the Niobrara Formation. The fossils of the animal looked similar to those of the species ''Pteranodon longiceps'', but the crests were set upright and in a slightly different position. In 1958, Sternberg and paleontologist Myrl V. Walker published a study about this peculiar find. In 1966, American paleontologist John Christian Harksen assigned the specimens found as a new species of ''Pteranodon'' called ''P. sternbergi'' due to its distinct upright crest that set it apart from ''P. longiceps''. Halsey W. Miller however, concluded a revision of the different species of ''Pteranodon'' in 19 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cretaceous–Paleogene Extinction Event
The Cretaceous–Paleogene (K–Pg) extinction event (also known as the Cretaceous–Tertiary extinction) was a sudden mass extinction of three-quarters of the plant and animal species on Earth, approximately 66 million years ago. With the exception of some ectothermic species such as sea turtles and crocodilians, no tetrapods weighing more than survived. It marked the end of the Cretaceous Period, and with it the Mesozoic era, while heralding the beginning of the Cenozoic era, which continues to this day. In the geologic record, the K–Pg event is marked by a thin layer of sediment called the K–Pg boundary, which can be found throughout the world in marine and terrestrial rocks. The boundary clay shows unusually high levels of the metal iridium, which is more common in asteroids than in the Earth's crust. As originally proposed in 1980 by a team of scientists led by Luis Alvarez and his son Walter, it is now generally thought that the K–Pg extinction was cause ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pteranodon Longiceps
''Pteranodon'' (); from Ancient Greek (''pteron'', "wing") and (''anodon'', "toothless") is a genus of pterosaur that included some of the largest known flying reptiles, with ''P. longiceps'' having a wingspan of . They lived during the late Cretaceous geological period of North America in present-day Kansas, Nebraska, Wyoming, South Dakota and Alabama. More fossil specimens of ''Pteranodon'' have been found than any other pterosaur, with about 1,200 specimens known to science, many of them well preserved with nearly complete skulls and articulated skeletons. It was an important part of the animal community in the Western Interior Seaway. ''Pteranodon'' was not a dinosaur. By definition, all dinosaurs belong to the group Dinosauria; ''Pteranodon'' belongs to the group Pterosauria. Nonetheless, ''Pteranodon'' is the most famous pterosaur, frequently featured in dinosaur media and strongly associated with dinosaurs by the general public. While not dinosaurs, pterosaurs such as ' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
