|
Pahvantia
''Pahvantia'' is an extinct genus of hurdiid radiodont from the Cambrian. It is known by a single species, ''Pahvantia hastata'', described from Wheeler Shale and Marjum Formation in Utah. Although it was once considered as filter feeder using large number of putative setae, this structures are later considered as misidentification of trunk materials. Description File:20210516 Radiodonta head sclerites Pahvantia hastata.png, Head sclerites File:20210909 Radiodonta frontal appendage Pahvantia hastata.png, Frontal appendage File:20210218 Pahvantia size.png, Size estimation File:Rsos210664f06 (cropped).jpg, KUMIP 314089 File:Pahvantia KUMIP 314089 with counterpart.png, KUMIP 314089 compared to counterpart, showing supposed podomeres Genus name ''Pahvantia'' is named after Pahvant in western Utah. It was originally described as possible arthropod with unknown affinity. One specimen is described as a specimen of ''Proboscicaris agnosta'', which is originally interpreted as bivalved ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pahvantia Fossil Interpretation Difference
''Pahvantia'' is an extinct genus of hurdiid radiodont from the Cambrian. It is known by a single species, ''Pahvantia hastata'', described from Wheeler Shale and Marjum Formation in Utah. Although it was once considered as filter feeder using large number of putative setae, this structures are later considered as misidentification of trunk materials. Description File:20210516 Radiodonta head sclerites Pahvantia hastata.png, Head sclerites File:20210909 Radiodonta frontal appendage Pahvantia hastata.png, Frontal appendage File:20210218 Pahvantia size.png, Size estimation File:Rsos210664f06 (cropped).jpg, KUMIP 314089 File:Pahvantia KUMIP 314089 with counterpart.png, KUMIP 314089 compared to counterpart, showing supposed podomeres Genus name ''Pahvantia'' is named after Pahvant in western Utah. It was originally described as possible arthropod with unknown affinity. One specimen is described as a specimen of ''Proboscicaris agnosta'', which is originally interpreted as bivalved ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radiodonta
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 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, Anomalocaris canadensis'', ''Hurdia, Hurdia victoria'', ''Peytoia nathorsti'', ''Titanokorys gainesii, Titanokorys gainessii, Cambroraster, Cambroraster falcatus'' and ''Amplectobelua, Amplectobelua symbrachiata'', the Ordovician ''Aegirocassis, Aegiroca ... [...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] |
Wheeler Shale
The Wheeler Shale (named by Charles Walcott) is a Cambrian ( 507 Ma) fossil locality world-famous for prolific agnostid and ''Elrathia kingii'' trilobite remains (even though many areas are barren of fossils) and represents a Konzentrat-Lagerstätte. Varied soft bodied organisms are locally preserved, a fauna (including ''Naraoia'', ''Wiwaxia'' and ''Hallucigenia'') and preservation style (carbonaceous film) normally associated with the more famous Burgess Shale. As such, the Wheeler Shale also represents a Konservat-Lagerstätten. Together with the Marjum Formation and lower Weeks Formation, the Wheeler Shale forms of limestone and shale exposed in one of the thickest, most fossiliferous and best exposed sequences of Middle Cambrian rocks in North America. At the type locality of Wheeler Amphitheater, House Range, Millard County, western Utah, the Wheeler Shale consists of a heterogeneous succession of highly calcareous shale, shaley limestone, mudstone and thi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Titanokorys
''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] |
Drumian
The Drumian is a stage of the Miaolingian Series of the Cambrian. It succeeds the Wuliuan and precedes the Guzhangian. The base is defined as the first appearance of the trilobite ''Ptychagnostus atavus'' around million years ago. The top is defined as the first appearance of another trilobite ''Lejopyge laevigata'' around million years ago. The GSSP is defined in the ''Drumian section'' () in the Drum Mountains, Millard County, Utah, United States. The stage was also named after the Drum Mountains. The section is an outcrop of the Wheeler Formation The Wheeler Shale (named by Charles Walcott) is a Cambrian ( 507 Ma) fossil locality world-famous for prolific agnostid and ''Elrathia kingii'' trilobite remains (even though many areas are barren of fossils) and represents a Konzent ..., a succession of calcareous shales. The precise base of the Drumian is a laminated limestone above the base of the Wheeler Formation. References Cambrian geochronology Geo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anomalocaridids
''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 ''A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cambrian Arthropods
The Cambrian Period ( ; sometimes symbolized 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 Cambrian biolo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tamisiocaris
''Tamisiocaris'' (from Latin ''tamisium'', sieve, and Greek ''karis'', crab, shrimp) is a radiodont genus initially only known from frontal appendages from the Buen Formation in Sirius Passet. Further specimens revealed that the frontal appendages were segmented and bore densely-packed auxiliary spines, which were adapted to suspension feeding in a manner analogous to modern baleen whales Baleen whales (systematic name Mysticeti), also known as whalebone whales, are a parvorder of carnivorous marine mammals of the infraorder Cetacea (whales, dolphins and porpoises) which use keratinaceous baleen plates (or "whalebone") in the .... See also * References {{Taxonbar, from=Q2391651 Anomalocaridids Prehistoric arthropod genera Cambrian arthropods Cambrian Greenland Fossils of Greenland Sirius Passet fossils Buen Formation Fossil taxa described in 2010 Cambrian genus extinctions ... [...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 the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Filter Feeder
Filter feeders are a sub-group of suspension feeding animals that feed by straining suspended matter and food particles from water, typically by passing the water over a specialized filtering structure. Some animals that use this method of feeding are clams, krill, sponges, baleen whales, and many fish (including some sharks). Some birds, such as flamingos and certain species of duck, are also filter feeders. Filter feeders can play an important role in clarifying water, and are therefore considered ecosystem engineers. They are also important in bioaccumulation and, as a result, as indicator organisms. Fish Most forage fish are filter feeders. For example, the Atlantic menhaden, a type of herring, lives on plankton caught in midwater. Adult menhaden can filter up to four gallons of water a minute and play an important role in clarifying ocean water. They are also a natural check to the deadly red tide. Extensive article on the role of menhaden in the ecosystem and possible resul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hurdia
''Hurdia'' is an extinct genus of hurdiid radiodont that lived 505 million years ago during the Cambrian Period. As a radiodont like ''Peytoia'' and ''Anomalocaris'', it is part of the ancestral lineage that led to euarthropods. Description ''Hurdia'' was one of the largest organisms in the Cambrian oceans, ''H. victoria'' reached approximately in length, while ''H. triangulata'' reached up to just . Its head bore a pair of rake-like frontal appendages which shovelled food into its pineapple-ring-like mouth (oral cone). Like other hurdiids, ''Hurdia'' bore a large frontal carapace protruding from its head composed of three sclerites: a central component known as the H-element and two lateral components known as P-elements. The function of this organ remains mysterious; it cannot have been protective as there was no underlying soft tissue. Originally, it is estimated that body flaps ran along the sides of the organisms, from which large gills were suspended. However, anatomy of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
