|
Radiodont
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 (Latin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Titanokorys Gainesii
''Titanokorys'' is a genus of extinct hurdiid radiodont (a grouping of primitive stem arthropods which lived during the early Paleozoic) that existed during the 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 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'', ''Anomalocaris'', ''Peytoia'', and ''Hurdia''. ''Titanokorys'' is distinguished from other Burgess Shale radiodonts because of its large anterior sclerite (head covering carapace) and a pair of spines on the anteroventral sides. Based on the shape of its appendages, ''Titanokorys'' is speculated to have ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anomalocaris
''Anomalocaris'' ("unlike other shrimp", or "abnormal shrimp") is an extinct genus of radiodont, an order of early-diverging stem-group arthropods. The first fossils of ''Anomalocaris'' were discovered in the ''Ogygopsis'' Shale of the Stephen Formation in British Columbia, Canada by Joseph Frederick Whiteaves, with more examples found by Charles Doolittle Walcott in the Burgess Shale unit of the Stephen Formation. Other closely related fossils have been found in the older Emu Bay Shale of Australia, as well as possibly elsewhere. Originally several fossilized parts discovered separately (the mouth, frontal appendages and trunk) were thought to be three separate creatures, a misapprehension corrected by Harry B. Whittington and Derek Briggs in a 1985 journal article. With a body length close to 40 centimetres, ''A. canadensis'' is thought to be one of the earliest examples of an apex predator, though others have been found in older Cambrian lagerstätten deposits. Discovery ''An ... [...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 equivoc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peytoia Nathorsti
''Peytoia'' is a genus of hurdiid radiodont that lived in the Cambrian period, containing two species, ''Peytoia nathorsti'' from the Miaolingian of Canada and '' Peytoia infercambriensis'' from Poland, dating to Cambrian Stage 3. Its two frontal appendages had long bristle-like spines, it had no fan tail, and its short stalked eyes were behind its large head. 108 specimens of ''Peytoia'' are known from the Greater Phyllopod bed, where they comprise 0.21% of the community. ''Peytoia nathorsti'' and its junior synonym ''Laggania cambria'' played a major role in the discovery of the radiodont body plan. Initially interpreted as a jellyfish and a sea cucumber respectively, they were eventually shown to be the mouthparts and body of a single animal, which bore ''Anomalocaris''-like appendages. ''Peytoia infercambriensis'' is the geologically oldest known radiodont species. Classification ''Peytoia'' belongs to the clade Hurdiidae, and is closely related to the contemporary genus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hurdiidae
Hurdiidae is an extinct cosmopolitan family of radiodonts, a group of 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 frontal appendages with distal region composed of 5 subequal blade-like endites, alongside the enlarged head carapaces and tetraradial mouthpart ( oral cone). The 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 medially, so that the appendages formed a basket-like structure. Some hurdiids had greater numbers of endites, with '' Cordaticaris'' bearing seven endi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anomalocarididae
Anomalocarididae (occasionally mis-spelt Anomalocaridae) is an extinct family of Cambrian radiodonts, a group of stem-group arthropods. Around 1990s and early 2010s, Anomalocarididae included all radiodont species, hence the previous equivalent of the common name "anomalocaridid" to the whole Radiodonta. This is no longer the case after the revision done by Vinther et al. 2014, as Anomalocarididae restricted to only ''Anomalocaris'' and, if any, a few of closely-related genera since then. Wu et al. 2021 accepted only ''Anomalocaris'' (excluding ''"A." saron'', ''"A." kunmingensis'' and ''"A." briggsi'') and '' Lenisicaris'' as the member of Anomalocarididae, while '' Paranomalocaris'' is questionably included by some studies as well. Anomalocarididae distinguished from the similar family Amplectobeluidae (e.g. '' Amplectobelua'', '' Lyrarapax'') by the presence of triradial oral cone and non-hypertrophied first distal endite. Compared to Hurdiidae and Tamisiocarididae, this ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Houcaris
''Houcaris'' is a genus of tamisiocarididid radiodonts known from Cambrian Series 2 of China and the United States. It contains two species, ''Houcaris saron'' and ''Houcaris magnabasis'', both of which were originally named as species of the related genus ''Anomalocaris''. The genus ''Houcaris'' was established for the two species in 2021 and honors Hou Xianguang, who had discovered and named the type species ''H. saron'' in 1995 along with his colleagues Jan Bergström and Per E. Ahlberg. Species ''Houcaris saron'' ''H. saron'', known from Maotianshan Shale in Yunnan, is first described in 1995 as ''Anomalocaris saron''. This species is only known from frontal appendages. There is a specimen (ELRC 20001) that is previously considered as whole body fossil of this species, but later study shows that this specimen is not belonging to this species, and later given own genus '' Innovatiocaris''. Length of frontal appendage is up to at least 12 cm. Sometimes considered to bel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aegirocassis
''Aegirocassis'' is an extinct genus of radiodont arthropod belonging to the family Hurdiidae that lived 480 million years ago during the early Ordovician. It is known by a single species, ''Aegirocassis benmoulai''. Van Roy initiated scientific study of the fossil, the earliest known of a "giant" filter-feeder discovered to date. ''Aegirocassis'' is considered to have evolved from early predatory radiodonts. Description File:20210221 Aegirocassis size.png, Size estimation File:YPM 527123 Aegirocassis benmoulai frontal appendage.png, Fossil of frontal appendage File:20191229 Radiodonta frontal appendage Aegirocassis benmoulai Aegirocassis benmoulae.png, Reconstruction of frontal appendage ''A. benmoulai'' was the largest known radiodont and largest animal existed in this period, and the length was described as exceeding in the scientific journal ''Nature''. The fossil was preserved with exceptional three-dimensional detail, unlike most other radiodont fossils, in which th ... [...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] |
Amplectobeluidae
''Amplectobeluidae'' is a clade of Cambrian radiodonts. Definition In 2014, ''Amplectobeluidae'' was defined as the most inclusive clade including '' Amplectobelua symbrachiata'' but not '' Anomalocaris canadensis'', '' Tamisiocaris borealis'', or '' Hurdia victoria''. Description Amplectobeluids could be recognized by frontal appendages with well-developed first distal endite, which forming a pincer-like structure that presumably better suited for a grasping function. Complete body fossils of amplectobeluids are only known by '' Amplectobelua'' and '' Lyrarapax'', both showing combination of characters resembling ''Anomalocaris ''Anomalocaris'' ("unlike other shrimp", or "abnormal shrimp") is an extinct genus of radiodont, an order of early-diverging stem-group arthropods. The first fossils of ''Anomalocaris'' were discovered in the ''Ogygopsis'' Shale of the Stephen Fo ...'' (i.e. streamlined body; small head with ovoid sclerites; well-developed swimming flaps; a pair o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amplectobelua
''Amplectobelua'' (meaning "embracing beast") is an extinct genus of late Early Cambrian amplectobeluid radiodont, a group of stem arthropods that mostly lived as free-swimming predators during the first half of the Paleozoic Era. Anatomy The body structures other than frontal appendages are only known from the type species ''Amplectobelua symbrachiata''. Like other radiodonts, ''Amplectobelua'' had a pair of jointed frontal appendages, a head covered by dorsal and lateral sclerites (the latter had been misinterpreted as huge eyes), a limbless body with dorsal gills (setal blades), and a series of flaps on both sides that extended along the length of its body. ''Amplectobelua'' had a specialized frontal appendage, in which it has a distinct 3-segmented shaft region and 12-segmented distal articulated region, and the spine on the fourth segment (first segment of distal articulated region) hooked forward to oppose the tip of the appendage, allowing it to grasp prey like a pi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dinocaridida
DinocarididaGreek, "Terrible crabs" – sometimes informally spelt Dinocarida, but the second 'id' is linguistically correct – see is a proposed fossil taxon of basal arthropods that flourished in the Cambrian period with occasional OrdovicianVan Roy, P.; Briggs, D. E. G. (2011). "A giant Ordovician anomalocaridid". Nature 473 (7348): 510–513. doi:10.1038/nature09920. edit and Devonian records. Characterized by a pair of frontal appendages and series of body flaps, the name of Dinocaridids comes from Greek, "deinos" and "caris" ("terrible crab"), referring to the suggested role of some of these members as the largest marine predators of their time. Dinocaridids are occasionally referred to as the 'AOPK group' by some literatures, as the group compose of Radiodonta (''Anomalocaris'' and relatives), Opabiniidae (''Opabinia'' and relatives), ''Pambdelurion'' and '' Kerygmachela.'' It is most likely paraphyletic, with ''Kerygmachela'' and ''Pambdelurion'' more basal than the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
