Limulitella
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]   |
|
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]   |
|
Bellinuroopsis
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]   |
|
Anacontium
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]   |
|
Genera
Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nomenclature, the genus name forms the first part of the binomial species name for each species within the genus. :E.g. ''Panthera leo'' (lion) and ''Panthera onca'' (jaguar) are two species within the genus '' Panthera''. ''Panthera'' is a genus within the family Felidae. The composition of a genus is determined by taxonomists. The standards for genus classification are not strictly codified, so different authorities often produce different classifications for genera. There are some general practices used, however, including the idea that a newly defined genus should fulfill these three criteria to be descriptively useful: # monophyly – all descendants of an ancestral taxon are grouped together (i.e. phylogenetic analysis should clearly demons ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Journal Of Paleontology
The ''Journal of Paleontology'' is a peer-reviewed scientific journal covering the field of paleontology. It is published by the Paleontological Society. Indexing The ''Journal of Paleontology'' is indexed in: *BIOSIS Previews *Science Citation Index *The Zoological Record *GeoRef __NOTOC__ The GeoRef database is a bibliographic database that indexes scientific literature in the geosciences, including geology. Coverage ranges from 1666 to the present for North American literature, and 1933 to the present for the rest of t ... References Paleontology journals Publications established in 1927 Academic journals published by learned and professional societies Cambridge University Press academic journals Bimonthly journals Paleontological Society {{paleo-journal-stub ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
1839 In Paleontology ...
Archosaurs Newly named pseudosuchians Data courtesy of George Olshevsky's dinosaur genera list. Paleontologists * Birth of Harry Govier Seeley, the paleontologist who invented the Saurischian/Ornithischian dinosaur dichotomy.{{cite book, last = Farlow, first = James O., author2= M. K. Brett-Surmann, title = The Complete Dinosaur, publisher = Indiana University Press, year = 1999, location = Bloomington, Indiana, pages = 15, isbn = 0-253-21313-4 References 1830s 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 Holocene epoch (roughly 11,700 years before present). It includes the study of fossi ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Belinurus
''Belinurus'' is an extinct genus of arthropods belonging to the order Xiphosura. It is part of the family Belinuridae, in the infraorder Belinurina. There used to be a longstanding academic controversy on whether ''Belinurus'' (König, 1820), ''Belinurus'' (Bronn, 1839) or ''Bellinurus'' (Pictet, 1846) had priority as a name over the genus. In 2021, the American paleontologist James C. Lamsdell did a study on this controversy and determined that the first name was not formally published and was therefore invalid and that the second one was valid and therefore had priority over the third one, the name of the genus thus being ''Belinurus''. The genus ''Belinurus'' is composed by the species ''B. trilobitoides'' (the type species In zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the species that contains the biological type specimen ...), ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Arthropod
Arthropods (, (gen. ποδός)) are invertebrate animals with an exoskeleton, a Segmentation (biology), segmented body, and paired jointed appendages. Arthropods form the phylum Arthropoda. They are distinguished by their jointed limbs and Arthropod cuticle, cuticle made of chitin, often Mineralization (biology), mineralised with calcium carbonate. The arthropod body plan consists of segments, each with a pair of appendages. Arthropods are bilaterally symmetrical and their body possesses an exoskeleton, external skeleton. In order to keep growing, they must go through stages of moulting, a process by which they shed their exoskeleton to reveal a new one. Some species have wings. They are an extremely diverse group, with up to 10 million species. The haemocoel, an arthropod's internal cavity, through which its haemolymph – analogue of blood – circulates, accommodates its interior Organ (anatomy), organs; it has an open circulatory system. Like their exteriors, the internal or ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
1910 In Paleontology
References * Makovicky, P. J., 2001, A Montanoceratops cerorhynchus (Dinosauria: Ceratopsia) braincase from the Horseshoe Canyon Formation of Alberta: In: Mesozoic Vertebrate Life, edited by Tanke, D. H., and Carpenter, K., Indiana University Press, pp. 243–262. ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Belinuropsis
''Belinuropsis'' is a dubious genus of prehistoric arthropod which contains one species, ''B. wigudensis'', from the Silurian period of New Brunswick, Canada. Matthew tried to describe ''Belinuropsis'' originally as a species of ''Belinurus''. Two specimens that match the Matthew's illustration of ''B. wigudensis'' have been located in the New Brunswick Museum paleontology collection and assigned catalogue numbers NBMG 3307 and NBMG 3308 (Miller, 1988). Examination of the specimens casts doubt on validity of the genus erected by Matthew. The material is poorly preserved and difficult to interpret, so, after examinations of the specimens, ''Belinuropsis'' has been considered as ''nomen dubium In binomial nomenclature, a ''nomen dubium'' (Latin for "doubtful name", plural ''nomina dubia'') is a scientific name that is of unknown or doubtful application. Zoology In case of a ''nomen dubium'' it may be impossible to determine whether a s ...''. References Carboniferous arth ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Triassic
The Triassic ( ) is a geologic period and system which spans 50.6 million years from the end of the Permian Period 251.902 million years ago ( Mya), to the beginning of the Jurassic Period 201.36 Mya. The Triassic is the first and shortest period of the Mesozoic Era. Both the start and end of the period are marked by major extinction events. The Triassic Period is subdivided into three epochs: Early Triassic, Middle Triassic and Late Triassic. The Triassic began in the wake of the Permian–Triassic extinction event, which left the Earth's biosphere impoverished; it was well into the middle of the Triassic before life recovered its former diversity. Three categories of organisms can be distinguished in the Triassic record: survivors from the extinction event, new groups that flourished briefly, and other new groups that went on to dominate the Mesozoic Era. Reptiles, especially archosaurs, were the chief terrestrial vertebrates during this time. A specialized subgroup of archo ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
1955 In Paleontology
Plants Pteridophyta Dinosaurs * ''Massospondylus'' gastroliths are documented.Bond (1955). Sanders, Manley, and Carpenter (2001), "Table 12.1" page 167. Newly named dinosaurs Data courtesy of George Olshevsky's dinosaur genera list. Synapsids Theriodonts Eutherians Cetaceans References {{portal, Paleontology * Bond, G. 1955. A note on dinosaur remains from the Forest Sandstone (Upper Karoo). Occasional Papers of the National Museum of Rhodesia 2: 795–800. * Sanders F, Manley K, Carpenter K. Gastroliths from the Lower Cretaceous sauropod Cedarosaurus weiskopfae. In: Tanke D.H, Carpenter K, editors. Mesozoic vertebrate life: new research inspired by the paleontology of Philip J. Currie. Indiana University Press; Bloomington, IN: 2001. pp. 166–180. 1950s 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 Holocene epoch ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |