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Lunataspis
''Lunataspis'' is the oldest known xiphosuran. It was first formally described by David Rudkin, Graham Young and Godfrey Nolan, from fossils found in northern Manitoba, Canada in 2005; the deposit dates from the Late Ordovician, .Chliboyko, J. ''Crabby Ancestors'', Canadian Geographic Magazine, April 2008, p. 25 Discovery and species The type species, ''L. aurora'', was described from remains found in the Konservat-Lagerstätten deposits of the Stony Mountain Formation, central Manitoba. The specific name ''aurora'' is Latin for 'dawn' and is also eponymous with the mythological Roman goddess. A second species, ''L. borealis'', was described in 2022 based on three specimens, including an adult (ROM IP 64616) and two juveniles or subadults (ROM IP 64617 and ROM IP 64618). All specimens were found in the upper member of the Gull River Formation in Kingston, Ontario. See also * 2005 in paleontology Protozoans Diatoms Plants Conifers Angiosperms Fungi Arthrop ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Xiphosura
Xiphosura () is an order of arthropods related to arachnids. They are more commonly known as horseshoe crabs (a name applied more specifically to the only extant family, Horseshoe crab, Limulidae). They first appeared in the Hirnantian (Late Ordovician). Currently, there are only four living species. Xiphosura contains one suborder, Xiphosurida, and several stem-genera. The group has hardly changed in appearance in hundreds of millions of years; the modern horseshoe crabs look almost identical to prehistoric genera and are considered to be living fossils. The most notable difference between ancient and modern forms is that the abdominal segments in present species are fused into a single unit in adults. Xiphosura were historically placed in the class Merostomata, although this term was intended to encompass also the Eurypterida, eurypterids, whence it denoted what is now known to be an unnatural (paraphyletic) group (although this is a grouping recovered in some recent cladistic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Xiphosura
Xiphosura () is an order of arthropods related to arachnids. They are more commonly known as horseshoe crabs (a name applied more specifically to the only extant family, Horseshoe crab, Limulidae). They first appeared in the Hirnantian (Late Ordovician). Currently, there are only four living species. Xiphosura contains one suborder, Xiphosurida, and several stem-genera. The group has hardly changed in appearance in hundreds of millions of years; the modern horseshoe crabs look almost identical to prehistoric genera and are considered to be living fossils. The most notable difference between ancient and modern forms is that the abdominal segments in present species are fused into a single unit in adults. Xiphosura were historically placed in the class Merostomata, although this term was intended to encompass also the Eurypterida, eurypterids, whence it denoted what is now known to be an unnatural (paraphyletic) group (although this is a grouping recovered in some recent cladistic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2008 In Paleontology
Protozoa New taxa Plants Angiosperms Monocots Arthropoda Arachnids Insects Xiphosurans Fishes Bony fish Placoderms General research *Hilton & Grande redescribe the fossil mooneyes of western North America synonymizing the genus ''Eohiodon'' with ''Hiodon''. *Cicimurri, Paris, & Everhart describe a partial dentition from a Holocephali chimaeroid fish found in the Niobrara Chalk. Amphibians Jenkins, F. A., jr, Shubin, N. H., Gatesy, S. M., and Warren, A., 2008, Gerrothorax pulcherrimus from the Upper Triassic Fleming Fjord Formation of East Greenland and a reassessment of head lifting in temnospondyl feeding: Journal of Vertebrate Paleontology, v. 28, n. 4, p. 935-950. Newly named amphibians Archosaurs Newly named pseudosuchians Newly named pterosaurs Dinosaurs * Oviraptorosaurian eggs with embryonic skeletons are discovered for the first time in China. * Mongolian Late Jurassic theropod fossils are found for the first time. * A new study on ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gull River Formation
The Gull River Formation is a geological formation of Middle Ordovician age (Caradoc Stage), which outcrops in Ontario, Canada. Lithologically, the formation is dominated by light grey to brown limestones and greenish gray dolomites with thin shale and sandstone interlayers. Fossil content Invertebrates Chelicerates Flora Acritarchs See also * List of fossiliferous stratigraphic units in Ontario This is a list of stratigraphic units in Ontario bearing fossils. See also References * {{Lists of fossiliferous stratigraphic units in Canada Geology of Ontario Ontario Ontario ( ; ) is one of the thirteen provinces and territo ... References Ordovician Ontario Ordovician southern paleotemperate deposits Ordovician southern paleotropical deposits {{Ontario-geo-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Xiphosurans
This list of xiphosurans is a comprehensive listing of all genera that have ever been included in the order Xiphosura, excluding purely vernacular terms. The list includes all commonly accepted genera, but also genera that are now considered invalid, doubtful (''nomen dubium''), or were not formally published (''nomen nudum''), as well as junior synonyms of more established names, genera that are no longer considered xiphosurans and misspellings. The list currently includes 54 names out of which 31 are considered valid xiphosuran genera. As of 2019, there were around 80 extinct species of xiphosurans and 4 extant species of xiphosurans recognized as valid. Naming conventions and terminology There is no "official" or "canonical" list of xiphosuran genera. The closest thing is found contained in the regularly updated ''Summary list of fossil spiders and their relatives'' in the World Spider Catalog, which include just the extinct species. The vast majority or all of the content of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2005 In Paleontology
Protozoans Diatoms Plants Conifers Angiosperms Fungi Arthropoda Arachnids Insects Xiphosurans * Fossils of '' Lunataspis'', the earliest known xiphosuran, are discovered in Canada. It was not given a formal description until 2008, however. Plesiosaurs New taxa Archosauromorphs Newly named Non-Avian dinosaurs Data courtesy of George Olshevsky's dinosaur genera list. Newly named birds Newly named pterosaurs Synapsids Non-mammalian Footnotes Complete author list As science becomes more collaborative, papers with large numbers of authors are becoming more common. To prevent the deformation of the tables, these footnotes list the contributors to papers that erect new genera and have many authors. References {{DEFAULTSORT:2005 In Paleontology 2000s in paleontology Paleontology Paleontology (), also spelled palaeontology or palæontology, is the scientific study of life that existed prior to, and sometimes including, the start of the Holoc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hirnantian
The Hirnantian is the final internationally recognized stage of the Ordovician Period of the Paleozoic Era. It was of short duration, lasting about 1.4 million years, from to Ma (million years ago). The early part of the Hirnantian was characterized by cold temperatures, major glaciation, and a severe drop in sea level. In the latter part of the Hirnantian, temperatures rose, the glaciers melted, and sea level returned to the same or to a slightly higher level than it had been prior to the glaciation. Most scientists believe that this climatic oscillation caused the major extinction event that took place during this time. In fact, the Hirnantian (also known as the End Ordovician and the Ordovician-Silurian) mass extinction event represents the second largest such event in geologic history. Approximately 85% of marine (sea-dwelling) species died. Only the End Permian mass extinction was larger. Unlike many smaller extinction events, however, the long-term consequences of the E ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ordovician Animals Of North America
The Ordovician ( ) is a geologic period and system, the second of six periods of the Paleozoic Era. The Ordovician spans 41.6 million years from the end of the Cambrian Period million years ago (Mya) to the start of the Silurian Period Mya. The Ordovician, named after the Welsh tribe of the Ordovices, was defined by Charles Lapworth in 1879 to resolve a dispute between followers of Adam Sedgwick and Roderick Murchison, who were placing the same rock beds in North Wales in the Cambrian and Silurian systems, respectively. Lapworth recognized that the fossil fauna in the disputed strata were different from those of either the Cambrian or the Silurian systems, and placed them in a system of their own. The Ordovician received international approval in 1960 (forty years after Lapworth's death), when it was adopted as an official period of the Paleozoic Era by the International Geological Congress. Life continued to flourish during the Ordovician as it did in the earlier Cambrian Perio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Late Ordovician Arthropods
Late may refer to: * LATE, an acronym which could stand for: ** Limbic-predominant age-related TDP-43 encephalopathy, a proposed form of dementia ** Local-authority trading enterprise, a New Zealand business law ** Local average treatment effect, a concept in econometrics Music * ''Late'' (album), a 2000 album by The 77s * Late!, a pseudonym used by Dave Grohl on his ''Pocketwatch'' album * Late (rapper), an underground rapper from Wolverhampton * "Late" (song), a song by Blue Angel * "Late", a song by Kanye West from ''Late Registration'' Other * Late (Tonga), an uninhabited volcanic island southwest of Vavau in the kingdom of Tonga * "Late" (''The Handmaid's Tale''), a television episode * LaTe, Oy Laivateollisuus Ab, a defunct shipbuilding company * Late may refer to a person who is Dead See also * * * ''Lates'', a genus of fish in the lates perch family * Later (other) * Tardiness * Tardiness (scheduling) In scheduling, tardiness is a measure of a delay in exe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kingston, Ontario
Kingston is a city in Ontario, Canada. It is located on the north-eastern end of Lake Ontario, at the beginning of the St. Lawrence River and at the mouth of the Cataraqui River (south end of the Rideau Canal). The city is midway between Toronto, Ontario and Montreal, Quebec. Kingston is also located nearby the Thousand Islands, a tourist region to the east, and the Prince Edward County tourist region to the west. Kingston is nicknamed the "Limestone City" because of the many heritage buildings constructed using local limestone. Growing European exploration in the 17th century, and the desire for the Europeans to establish a presence close to local Native occupants to control trade, led to the founding of a French trading post and military fort at a site known as "Cataraqui" (generally pronounced /kætə'ɹɑkweɪ/, "kah-tah-ROCK-way") in 1673. This outpost, called Fort Cataraqui, and later Fort Frontenac, became a focus for settlement. Since 1760, the site of Kingston, Ont ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Royal Ontario Museum
The Royal Ontario Museum (ROM) is a museum of art, world culture and natural history in Toronto, Ontario, Canada. It is one of the largest museums in North America and the largest in Canada. It attracts more than one million visitors every year, making the ROM the most-visited museum in Canada. The museum is north of Queen's Park, in the University of Toronto district, with its main entrance on Bloor Street West. Museum subway station is named after the ROM and, since a 2008 renovation, is decorated to resemble the institution's collection at the platform level. Established on April 16, 1912, and opened on March 19, 1914, the museum has maintained close relations with the University of Toronto throughout its history, often sharing expertise and resources. The museum was under the direct control and management of the University of Toronto until 1968, when it became an independent Crown agency of the Government of Ontario. Today, the museum is Canada's largest field-research in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Species
In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. Other ways of defining species include their karyotype, DNA sequence, morphology, behaviour or ecological niche. In addition, paleontologists use the concept of the chronospecies since fossil reproduction cannot be examined. The most recent rigorous estimate for the total number of species of eukaryotes is between 8 and 8.7 million. However, only about 14% of these had been described by 2011. All species (except viruses) are given a two-part name, a "binomial". The first part of a binomial is the genus to which the species belongs. The second part is called the specific name or the specific epithet (in botanical nomenclature, also sometimes i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
