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Radiodonts
Radiodonta is an extinct order of stem-group arthropods that was successful worldwide during the Cambrian period. They may be referred to as radiodonts, radiodontans, radiodontids, anomalocarids, or anomalocaridids, although the last two originally refer to the family Anomalocarididae, which previously included all species of this order but is now restricted to only a few species. Radiodonts are distinguished by their distinctive frontal appendages, which are morphologically diverse and used for a variety of functions. Radiodonts included the earliest large predators known, but they also included sediment sifters and filter feeders. Some of the most famous species of radiodonts are the Cambrian taxa ''Anomalocaris canadensis'', ''Hurdia victoria'', ''Peytoia nathorsti'', '' Titanokorys gainessii, Cambroraster falcatus'' and '' Amplectobelua symbrachiata'', the Ordovician '' Aegirocassis benmoulai'' and the Devonian ''Schinderhannes bartelsi''. Etymology The name Radiodonta ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cambrian
The Cambrian Period ( ; sometimes symbolized C with bar, Ꞓ) was the first geological period of the Paleozoic Era, and of the Phanerozoic Eon. The Cambrian lasted 53.4 million years from the end of the preceding Ediacaran Period 538.8 million years ago (mya) to the beginning of the Ordovician Period mya. Its subdivisions, and its base, are somewhat in flux. The period was established as "Cambrian series" by Adam Sedgwick, who named it after Cambria, the Latin name for 'Cymru' (Wales), where Britain's Cambrian rocks are best exposed. Sedgwick identified the layer as part of his task, along with Roderick Murchison, to subdivide the large "Transition Series", although the two geologists disagreed for a while on the appropriate categorization. The Cambrian is unique in its unusually high proportion of sedimentary deposits, sites of exceptional preservation where "soft" parts of organisms are preserved as well as their more resistant shells. As a result, our understanding of the Ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hurdiidae
Hurdiidae is an extinct cosmopolitan distribution, cosmopolitan Family (biology), family of radiodonts, a group of Crown group#Stem groups, stem-group arthropods, which lived during the Paleozoic Era. It is the most long-lived radiodont clade, lasting from the Cambrian period to the Devonian period. Description Hurdiidae is characterized by Radiodonta#Frontal appendage, frontal appendages with distal region composed of 5 subequal blade-like endites, alongside the enlarged head carapaces and tetraradial mouthpart (Radiodonta#Oral cone, oral cone). The Radiodonta#Frontal appendage, frontal appendages of hurdiids have a distinctive morphology, with the appendage of most species bearing five equally-sized elongate blade-like ventral spines known as endites. Subsequent podomeres were reduced in size and with only small endites or none. Each podomere bore only a single endite, unlike other radiodonts, in which the endites were paired. In most species, the endites were curved med ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Schinderhannes (genus)
''Schinderhannes bartelsi'' is a species of hurdiid radiodont (anomalocaridid) known from one specimen from the lower Devonian Hunsrück Slates. Its discovery was astonishing because previously, radiodonts were known only from exceptionally well-preserved fossil beds (Lagerstätten) from the Cambrian, 100 million years earlier. Discovery The single specimen was discovered in the Eschenbach-Bocksberg Quarry in Bundenbach, and is named after the outlaw Schinderhannes who frequented the area. Its specific epithet ''bartelsi'' honours Christoph Bartels, a Hunsrück Slate expert. The specimen is now housed in the Naturhistorisches Museum, Mainz. Morphology ''Schinderhannes'' is about long in full body length (6.8cm long excluding telson). Like other radiodonts, the head bears a pair of spiny frontal appendages, a radially-arranged ventral mouthpart ( oral cone), and a pair of large lateral compound eyes. Detailed morphology of the frontal appendages and oral cone are equivocal due ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ordovician
The Ordovician ( ) is a geologic period and System (geology), system, the second of six periods of the Paleozoic Era (geology), 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 Celtic Britons, 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 (geology), rock beds in North Wales in the Cambrian and Silurian systems, respectively. Lapworth recognized that the fossil fauna in the disputed Stratum, 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 Union of Geological Sciences, Intern ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Titanokorys Gainesii
''Titanokorys'' is a genus of extinct hurdiid radiodont Radiodonta is an extinct Order (biology), order of stem-group arthropods that was successful worldwide during the Cambrian period. They may be referred to as radiodonts, radiodontans, radiodontids, anomalocarids, or anomalocaridids, although the ... (a grouping of primitive Stem-group, stem arthropods which lived during the early Paleozoic) that existed during the Wuliuan, mid Cambrian. It is the largest member of its family from the Cambrian, with a body length of long, making it one of the largest animals of the time. It bears a resemblance to the related genus ''Cambroraster''. Fossils of ''T. gainesi'' were first found within Marble Canyon (Canadian Rockies), Marble Canyon in 2018. The fossils were not named until 2021 because they were assumed to be giant specimens of ''Cambroraster''. The creature was one of several genera of radiodonts known from the Burgess Shale, with some of the others being ''Cambroraster'', ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nature (journal)
''Nature'' is a British weekly scientific journal founded and based in London, England. As a multidisciplinary publication, ''Nature'' features peer-reviewed research from a variety of academic disciplines, mainly in science and technology. It has core editorial offices across the United States, continental Europe, and Asia under the international scientific publishing company Springer Nature. ''Nature'' was one of the world's most cited scientific journals by the Science Edition of the 2019 ''Journal Citation Reports'' (with an ascribed impact factor of 42.778), making it one of the world's most-read and most prestigious academic journals. , it claimed an online readership of about three million unique readers per month. Founded in autumn 1869, ''Nature'' was first circulated by Norman Lockyer and Alexander Macmillan as a public forum for scientific innovations. The mid-20th century facilitated an editorial expansion for the journal; ''Nature'' redoubled its efforts in exp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arthropods
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] |
Stem-group
In phylogenetics, the crown group or crown assemblage is a collection of species composed of the living representatives of the collection, the most recent common ancestor of the collection, and all descendants of the most recent common ancestor. It is thus a way of defining a clade, a group consisting of a species and all its extant or extinct descendants. For example, Neornithes (birds) can be defined as a crown group, which includes the most recent common ancestor of all modern birds, and all of its extant or extinct descendants. The concept was developed by Willi Hennig, the formulator of phylogenetic systematics, as a way of classifying living organisms relative to their extinct relatives in his "Die Stammesgeschichte der Insekten", and the "crown" and "stem" group terminology was coined by R. P. S. Jefferies in 1979. Though formulated in the 1970s, the term was not commonly used until its reintroduction in 2000 by Graham Budd and Sören Jensen. Contents of the crown gr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Order (biology)
Order ( la, wikt:ordo#Latin, ordo) is one of the eight major hierarchical taxonomic ranks in Linnaean taxonomy. It is classified between Family_(biology), family and Class_(biology), class. In biological classification, the order is a taxonomic rank used in the classification of organisms and recognized by the nomenclature codes. An immediately higher rank, superorder, is sometimes added directly above order, with suborder directly beneath order. An order can also be defined as a group of related families. What does and does not belong to each order is determined by a taxonomist, as is whether a particular order should be recognized at all. Often there is no exact agreement, with different taxonomists each taking a different position. There are no hard rules that a taxonomist needs to follow in describing or recognizing an order. Some taxa are accepted almost universally, while others are recognized only rarely. The name of an order is usually written with a capital letter. Fo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paranomalocaris
''Paranomalocaris'' is a genus of primitive radiodont recovered from Wulongqing Formation, eastern Yunnan. It contains two species, ''Paranomalocaris multisegmentalis'' and ''P. simplex''. It is only known from its frontal appendage (now known to be homologous to the labrum of euarthropod Arthropods (, (gen. ποδός)) are invertebrate animals with an exoskeleton, a segmented body, and paired jointed appendages. Arthropods form the phylum Arthropoda. They are distinguished by their jointed limbs and cuticle made of chitin, oft ... and primary antennae of Onychophorans). The frontal appendage features endites with numerous auxiliary spines, and at least 22 segments (podomeres), hence the specific name ''multisegmentalis''. References {{Taxonbar, from=Q65042329 Anomalocaridids Fossil taxa described in 2013 Cambrian arthropods ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Laminacaris
''Laminacaris'' is a genus of extinct stem-group arthropods (Radiodonta) that lived during the Cambrian period. It is monotypic with a single species ''Laminacaris chimera'', the fossil of which was described from the Chengjian biota of China in 2018. Around the same time, two specimens that were similar or of the same species were discovered at the Kinzers Formation in Pennsylvania, USA. The first specimens from China were three frontal appendages, without the other body parts. ''Laminacaris'' specimens were discovered from three sites in China: the mudstones of the Yu'anshan Member of the Chiungchussu Formation in eastern Yunnan Province, the Mafang section in the Haikou area at Kunming, and the Heimadi section, Chengjiang. The name is derived from Latin words, ''lamina'' meaning thin blade, and ''caris'' for crab; the species name refers to a Greek mythological creature, ''Chimera'', that has a body composed of parts of more than one animal. In 2022, it is treated that is poss ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Innovatiocaris
''Innovatiocaris'' (meaning "innovation crab") is a genus of radiodont of uncertain family from the early Cambrian Chengjiang Lagerstätte of Yunnan Province, China. The genus contains two named species, ''I. maotianshanensis'', known from a nearly complete individual and isolated frontal appendages, and ''I.''? ''multispiniformis'', known from a complete frontal appendage. Discovery and naming The holotype specimen of ''Innovatiocaris maotianshanensis'', ELRC 20001 was long considered in scientific literature as "''Anomalocaris'' sp". or ''Anomalocaris saron'' (=''Houcaris saron''). However, in 2022, Zeng ''et al''. described it as a new genus and species of radiodont. The holotype consists of the nearly complete remains of a young individual, preserved on a part and counterpart. A brief description of the specimen was provided in Chen ''et al''. (1994), but, despite its popularity in popular science literature, it did not receiv a detailed description until 2022. ELRC 2001 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
