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Oxalaia
''Oxalaia'' (in reference to the African deity '' Oxalá'') is a genus of spinosaurid dinosaur that lived in what is now the Northeast Region of Brazil during the Cenomanian stage of the Late Cretaceous period, sometime between 100.5 and 93.9 million years ago. Its only known fossils were found in 1999 on Cajual Island in the rocks of the Alcântara Formation, which is known for its abundance of fragmentary, isolated fossil specimens. The remains of ''Oxalaia'' were described in 2011 by Brazilian palaeontologist Alexander Kellner and colleagues, who assigned the specimens to a new genus containing one species, ''Oxalaia quilombensis''. The species name refers to the Brazilian quilombo settlements. ''Oxalaia quilombensis'' is the eighth officially named theropod species from Brazil and the largest carnivorous dinosaur discovered there. It is closely related to the African genus ''Spinosaurus'', and/or may be a junior synonym of this taxon. Although ''Oxalaia'' is known only from ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spinosaur Taxonomy Map
The Spinosauridae (or spinosaurids) are a clade or family of tetanuran theropod dinosaurs comprising ten to seventeen known genera. They came into prominence during the Cretaceous period. Spinosaurid fossils have been recovered worldwide, including Africa, Europe, South America and Asia. Their remains have generally been attributed to the Early to Mid Cretaceous. Spinosaurids were large bipedal carnivores. Their crocodilian-like skulls were long, low and narrow, bearing conical teeth with reduced or absent serrations. The tips of their upper and lower jaws fanned out into a spoon-shaped structure similar to a rosette, behind which there was a notch in the upper jaw that the expanded tip of the lower jaw fit into. The nostrils of spinosaurids were retracted to a position further back on the head than in most other theropods, and they had bony crests on their heads along the midline of their skulls. Their robust shoulders wielded stocky forelimbs, with three-fingered hands that bo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spinosauridae
The Spinosauridae (or spinosaurids) are a clade or family of tetanuran theropod dinosaurs comprising ten to seventeen known genera. They came into prominence during the Cretaceous period. Spinosaurid fossils have been recovered worldwide, including Africa, Europe, South America and Asia. Their remains have generally been attributed to the Early to Mid Cretaceous. Spinosaurids were large bipedal carnivores. Their crocodilian-like skulls were long, low and narrow, bearing conical teeth with reduced or absent serrations. The tips of their upper and lower jaws fanned out into a spoon-shaped structure similar to a rosette, behind which there was a notch in the upper jaw that the expanded tip of the lower jaw fit into. The nostrils of spinosaurids were retracted to a position further back on the head than in most other theropods, and they had bony crests on their heads along the midline of their skulls. Their robust shoulders wielded stocky forelimbs, with three-fingered hands that b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spinosaurus
''Spinosaurus'' (; ) is a genus of spinosaurid dinosaur that lived in what now is North Africa during the Cenomanian to upper Turonian stages of the Late Cretaceous period, about 99 to 93.5 million years ago. The genus was known first from Egyptian remains discovered in 1912 and described by German palaeontologist Ernst Stromer in 1915. The original remains were destroyed in World War II, but additional material came to light in the early 21st century. It is unclear whether one or two species are represented in the fossils reported in the scientific literature. The best known species is ''S. aegyptiacus'' from Egypt, although a potential second species, ''S. maroccanus'', has been recovered from Morocco. The contemporary spinosaurid genus ''Sigilmassasaurus'' has also been synonymized by some authors with ''S. aegyptiacus'', though other researchers propose it to be a distinct taxon. Another possible junior synonym is ''Oxalaia'' from the Alcântara Formation in Brazil. ' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alcântara Formation
The Alcântara Formation is a geological formation in northeastern Brazil whose strata date back to the Cenomanian of the 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 .... Fossil content Dinosaurs Pterosauria Crocodylomorphs Turtles Squamates Fish References {{DEFAULTSORT:Alcantara Formation Geologic formations of Brazil Upper Cretaceous Series of South America Cretaceous Brazil Cenomanian Stage Sandstone formations Shale formations Conglomerate formations Shallow marine deposits Fossiliferous stratigraphic units of South America Paleontology in Brazil Formations ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alexander Kellner
Alexander Wilhelm Armin Kellner (born September 26, 1961) is a Brazilian geologist and paleontologist who is a leading expert in the field of studying pterosaurs. His research has focused mainly on fossil reptiles from the Cretaceous Period, including extinct dinosaurs and crocodylomorphs. Kellner has over 500 publications to his name, has published more than 160 primary studies and two science books. He has participated in paleontological expeditions to many locations including Brazil, Chile, Iran, the United States, Argentina, China, and Antarctica. His scientific achievements include the description of more than thirty species. For his work he has received several honors and prizes, including the TWAS Prize for Earth Sciences from The World Academy of Sciences and admission to the National Order of Scientific Merit (class Comendador), one Brazil's most prestigious awards. Biography Kellner was born in Vaduz, Liechtenstein, son of a German father and Austrian mother. In hi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cajual Island
The island of Cajual is located in the Baía de São Marcos near to Alcântara, Maranhão, Brazil. The island is an important Brazilian paleontological site, where fossils of animals such as ''Spinosaurus'' and ''Sigilmassasaurus'' were found, and also such plants as conifers and ferns. The finds include the remains of the largest carnivorous dinosaur in Brazil. Traces of the maxillary and nostril of the specimen were found. Known as ''Oxalaia quilombensis'', the species is part of the family of dinosaurs known as Spinosauridae, with elongated skulls and spines along the back. The presence of fossils also present in Africa proves that the continents were once united, forming Gondwana. The "Lage of the Joker", where the fossils are found, is up to 2 meters below the water at high tide, so it can only be visited for only a few hours a day. Currently, the island of Cajual is home to a small community of ''quilombola A ''quilombola'' () is an Afro-Brazilian resident of ''quil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2011 In Paleontology
Protozoa New taxa Plants Ferns and fern allies Gymnosperms Gymnosperm research *An amplified whole plant reconstruction of the Ypresian Princeton chert pine '' Pinus arnoldii'', expanding the diagnosis to include ''P. similkameenensis'' (Miller, 1973 Events January * January 1 - The United Kingdom, the Republic of Ireland and Denmark enter the European Economic Community, which later becomes the European Union. * January 15 – Vietnam War: Citing progress in peace negotiations, U.S. ...) foliage and wood plus unnamed pollens cones found in attachment to the ''P. arnoldii'' ovulate cones is published by Klymiuk, Stockey, & Rothwell. Angiosperms Nematoda Lobopods Vetulicolians Molluscs Arthropods Fishes Amphibians Newly named lepospondyls Newly named temnospondyls Newly named lissamphibians Basal reptiles Newly named captorhinids Newly named basal diapsids Newly named ichthyosaurs Lepidosauromorphs Newly named saurosphargids New ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Theropoda
Theropoda (; ), whose members are known as theropods, is a dinosaur clade that is characterized by hollow bones and three toes and claws on each limb. Theropods are generally classed as a group of saurischian dinosaurs. They were ancestrally carnivorous, although a number of theropod groups evolved to become herbivores and omnivores. Theropods first appeared during the Carnian age of the late Triassic Period (geology), period 231.4 million years ago (Year#SI prefix multipliers, Ma) and included all the large terrestrial carnivores from the Early Jurassic until at least the close of the Cretaceous, about 66 Ma. In the Jurassic, birds evolved from small specialized coelurosaurian theropods, and are today represented by about 10,500 living species. Biology Diet and teeth Theropods exhibit a wide range of diets, from insectivores to herbivores and carnivores. Strict carnivory has always been considered the ancestral diet for theropods as a group, and a wider variety of di ... [...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] |
Crocodilia
Crocodilia (or Crocodylia, both ) is an order of mostly large, predatory, semiaquatic reptiles, known as crocodilians. They first appeared 95 million years ago in the Late Cretaceous period ( Cenomanian stage) and are the closest living relatives of birds, as the two groups are the only known survivors of the Archosauria. Members of the order's total group, the clade Pseudosuchia, appeared about 250 million years ago in the Early Triassic period, and diversified during the Mesozoic era. The order Crocodilia includes the true crocodiles (family Crocodylidae), the alligators and caimans (family Alligatoridae), and the gharial and false gharial (family Gavialidae). Although the term 'crocodiles' is sometimes used to refer to all of these, crocodilians is a less ambiguous vernacular term for members of this group. Large, solidly built, lizard-like reptiles, crocodilians have long flattened snouts, laterally compressed tails, and eyes, ears, and nostrils at the top ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Piscivorous
A piscivore () is a carnivorous animal that eats primarily fish. The name ''piscivore'' is derived . Piscivore is equivalent to the Greek-derived word ichthyophage, both of which mean "fish eater". Fish were the diet of early tetrapod evolution (via water-bound amphibians during the Devonian period); insectivory came next; then in time, the more terrestrially adapted reptiles and synapsids evolved herbivory. Almost all predatory fishes (most sharks, tuna, billfishes, pikes etc.) are obligated piscivores. Some non-piscine aquatic animals, such as whales, sea lion and crocodilians, are not completely piscivorous, often also preying on invertebrates, marine mammals, waterbirds and even wading land animals in addition to fish; while others, such as the bulldog bat and gharial, are strictly dependent on fish for food. Some creatures, including cnidarians, octopuses, squid, spiders, cetaceans, grizzly bears, jaguars, wolves, snakes, turtles and sea gulls, may have fish as significa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gondwana
Gondwana () was a large landmass, often referred to as a supercontinent, that formed during the late Neoproterozoic (about 550 million years ago) and began to break up during the Jurassic period (about 180 million years ago). The final stages of break-up, involving the separation of Antarctica from South America (forming the Drake Passage) and Australia, occurred during the Paleogene. Gondwana was not considered a supercontinent by the earliest definition, since the landmasses of Baltica, Laurentia, and Siberia were separated from it. To differentiate it from the Indian region of the same name (see ), it is also commonly called Gondwanaland. Gondwana was formed by the accretion of several cratons. Eventually, Gondwana became the largest piece of continental crust of the Palaeozoic Era, covering an area of about , about one-fifth of the Earth's surface. During the Carboniferous Period, it merged with Laurasia to form a larger supercontinent called Pangaea. Gondwana (and Pan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
