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Agmata
Agmata is a proposed extinct phylum of small animals with a calcareous conical shell. They were originally thought to be cephalopods or annelid worms. The living animals filled up to five-sixths of their shell with laminae, angled layers composed of grains of quartz or calcium carbonate detritus from the environment cemented together, with larger grains near the shell wall and smaller grains near the center. A very fine tube ran through the center of the shell. The grains may be of quartz or calcium carbonate, but are of specific shapes and materials that are rare in the surrounding rock. Though the body of the living animal is not preserved, it had to be able to find, choose, and retrieve rare grains from its environment to build the laminae. The phylum's name comes from the Greek word for "fragments", referring to these fine fragments and grains of detritus. It was proposed by the paleontologist and geologist (1928–2006) in 1977 to house the agglutinating Early Cambrian fos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Salterella
''Salterella'' is an enigmatic Cambrian genus with a small, conical, calcareous shell that appears to be septate, but is rather filled with stratified laminar deposits. The shell contains grains of sediment, which are obtained selectively (with a preference for denser grains) by a manner also observed in foramanifera. The genus was established by Elkanah Billings in 1861, and was named after the English palaeontologist John William Salter. The genus is known from multiple locations worldwide, such as Newfoundland and Labrador and Quebec in Canada, Svalbard, the Scottish Highlands and Argentina. The related fossil genus '' Volborthella'' was formerly placed in synonymy with ''Salterella'' by Ellis L. Yochelson in 1983, due to the similarities between the two genera (though ''Volborthella'' notably lacks an outer calcareous shell). However, ''Volborthella'' was later accepted as a separate genus again by Yochelson & Kisselev in 2003. Both genera are currently placed in the Sal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vologdinella
''Vologdinella'' is a poorly known genus of extinct animals of uncertain classification with small cylindrical shells. The animals are known from Middle Cambrian fossils from a Paleozoic limestone in the Chingiz Mountains of Kazakhstan. The genus was established by Russian paleontologist Zakhar Grigoryevich Balashov in 1962 for a single species, ''Vologdinella antiqua'', which was originally described and illustrated as ''Orthoceras? antiquus'' by in 1931. The genus was historically classified as a cephalopod, though it has since been removed from this group. ''Vologdinella'' bears superficial resemblance to the Early Cambrian ''Volborthella''. In the same work establishing the former genus, the two genera were classified within their own families – Vologdinellidae and Volborthellidae, respectively – within the order Volborthellida. ''Volborthella'' was later included in Agmata Agmata is a proposed extinct phylum of small animals with a calcareous conical shell. They were ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Salterellidae
Salterellidae is a family of enigmatic fossil genera from the Early to Middle Cambrian. It was originally created for the genus ''Salterella'' by Charles Doolittle Walcott, who placed it in the group Pteropoda. It was later placed in Agmata, a proposed extinct phylum by Ellis L. Yochelson which is accepted by some other authors. Genera * †'' Ellisell'' Peel & Berg-Madsen, 1988 ** †''Ellisell yochelsoni'' Peel & Berg-Madsen, 1988 * †''Salterella'' Billings, 1861 ** †''Salterella conulata'' Clark, 1924 ** †''Salterella maccullochi'' ( Murchison, 1859) * †''Volborthella'' Schmidt, 1888 ** †''Volborthella tenuis'' Schmidt Schmidt may refer to: * Schmidt (surname), including list of people with the surname * Schmidt (singer) (born 1990), German pop and jazz singer * Schmidt (lunar crater), a small lunar impact crater * Schmidt (Martian crater), a List of craters on ..., 1888 References Prehistoric animal families Prehistoric animal enigmatic taxa Taxa named ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ellisell
''Ellisell'' is a Middle Cambrian genus of fossils from Denmark. It contains only one species, ''Ellisell yochelsoni''. Both the genus and species are named after the paleontologist and geologist (1928–2006), who had turned 60 at the time the fossils were first described. The genus was originally placed in the family Salterellidae of the phylum Agmata; this placement was rejected by Yochelson & Kisselev (2003), but was restored by Peel (2016). ''Ellisell'' is distinguished from ''Salterella ''Salterella'' is an enigmatic Cambrian genus with a small, conical, calcareous shell that appears to be septate, but is rather filled with stratified laminar deposits. The shell contains grains of sediment, which are obtained selectively (with ...'' by its slowly expanding conch and the resulting cylindrical apertural cavity, compared to the latter's more rapidly expanding conch and cone-shaped apertural cavity. References Enigmatic prehistoric animal genera Fossils of Denmark [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Volborthella
''Volborthella'' is an animal of uncertain classification, whose fossils pre-date . It has been considered for a period a cephalopod. However discoveries of more detailed fossils showed that ''Volborthella''’s small, conical shell was not secreted but built from grains of the mineral silicon dioxide (silica), and that it was not divided into a series of compartments by septa as those of fossil shelled cephalopods and the living ''Nautilus'' are. This illusion was a result of the laminated texture of the organisms' tests. Therefore, ''Volborthella''’s classification is now uncertain. It has been speculated that it may in fact represent a sclerite of a larger organism, on the basis of one specimen; however, it may be premature to accept this hypothesis, as the arrangement of sclerites producing this impression may have occurred by chance. The Ordovician scleritome-bearing '' Curviconophorus'', as well as the Halwaxiids, lobopods and echinoderms, demonstrate the diversity of orga ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phylum
In biology, a phylum (; plural: phyla) is a level of classification or taxonomic rank below kingdom and above class. Traditionally, in botany the term division has been used instead of phylum, although the International Code of Nomenclature for algae, fungi, and plants accepts the terms as equivalent. Depending on definitions, the animal kingdom Animalia contains about 31 phyla, the plant kingdom Plantae contains about 14 phyla, and the fungus kingdom Fungi contains about 8 phyla. Current research in phylogenetics is uncovering the relationships between phyla, which are contained in larger clades, like Ecdysozoa and Embryophyta. General description The term phylum was coined in 1866 by Ernst Haeckel from the Greek (, "race, stock"), related to (, "tribe, clan"). Haeckel noted that species constantly evolved into new species that seemed to retain few consistent features among themselves and therefore few features that distinguished them as a group ("a self-contained unity" ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Middle Cambrian
Middle or The Middle may refer to: * Centre (geometry), the point equally distant from the outer limits. Places * Middle (sheading), a subdivision of the Isle of Man * Middle Bay (other) * Middle Brook (other) * Middle Creek (other) * Middle Island (other) * Middle Lake (other) * Middle Mountain, California * Middle Peninsula, Chesapeake Bay, Virginia * Middle Range, a former name of the Xueshan Range on Taiwan Island * Middle River (other) * Middle Rocks, two rocks at the eastern opening of the Straits of Singapore * Middle Sound, a bay in North Carolina * Middle Township (other) * Middle East Music *Middle (song), "Middle" (song), 2015 *The Middle (Jimmy Eat World song), "The Middle" (Jimmy Eat World song), 2001 *The Middle (Zedd, Maren Morris and Grey song), "The Middle" (Zedd, Maren Morris and Grey song), 2018 *"Middle", a song by Rocket from the Crypt from their 1995 album ''Scream, Dracula, Scream!'' *"The Middle ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cambrian Fossil Record
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] |
Foraminifera
Foraminifera (; Latin for "hole bearers"; informally called "forams") are single-celled organisms, members of a phylum or class of amoeboid protists characterized by streaming granular Ectoplasm (cell biology), ectoplasm for catching food and other uses; and commonly an external shell (called a "Test (biology), test") of diverse forms and materials. Tests of chitin (found in some simple genera, and Textularia in particular) are believed to be the most primitive type. Most foraminifera are marine, the majority of which live on or within the seafloor sediment (i.e., are benthos, benthic), while a smaller number float in the water column at various depths (i.e., are planktonic), which belong to the suborder Globigerinina. Fewer are known from freshwater or brackish conditions, and some very few (nonaquatic) soil species have been identified through molecular analysis of small subunit ribosomal DNA. Foraminifera typically produce a test (biology), test, or shell, which can have eithe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lethaia
''Lethaia'' is a quarterly peer-reviewed scientific journal of Earth science, covering research on palaeontology and stratigraphy. Now published by Wiley-Blackwell, it was originally published by the International Commission on Stratigraphy. It is an official publication of the International Palaeontological Association and the International Commission on Stratigraphy. The journal had a 2012 impact factor The impact factor (IF) or journal impact factor (JIF) of an academic journal is a scientometric index calculated by Clarivate that reflects the yearly mean number of citations of articles published in the last two years in a given journal, as i ... of 2.488, ranking it 7th out of 48 journals in the category "Paleontology", though its IF has since declined. References External links * Paleontology journals Wiley-Blackwell academic journals English-language journals Publications established in 1968 Quarterly journals {{paleontology-journal-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
GFF (journal)
GFF may refer to: Entertainment * Girlfriends Films, an American pornographic studio * Glasgow Film Festival, in Scotland * Gothenburg Film Festival, in Sweden Sports * Gabonese Football Federation * Gambia Football Federation * Georgian Football Federation * Göteborgs FF, Swedish football club * Gothenburg Football Association * Guinean Football Federation * Guyana Football Federation Other uses * ''GFF'' (journal), a geology journal * General feature format, a file format used for describing genes * Göteborgs FyrverkeriFabrik, a Swedish fireworks company * Griffith Airport, in New South Wales, Australia * Griffith railway station Griffith railway station is located on the Yanco-Griffith line in New South Wales, Australia. It serves the city of Griffith. History Griffith station opened on 3 July 1916 when the Temora-Roto line was extended from Barellan. It served as ..., in New South Wales, Australia * Guild of Fine Food, a British family-owned company ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Annelid
The annelids (Annelida , from Latin ', "little ring"), also known as the segmented worms, are a large phylum, with over 22,000 extant species including ragworms, earthworms, and leeches. The species exist in and have adapted to various ecologies – some in marine environments as distinct as tidal zones and hydrothermal vents, others in fresh water, and yet others in moist terrestrial environments. The Annelids are bilaterally symmetrical, triploblastic, coelomate, invertebrate organisms. They also have parapodia for locomotion. Most textbooks still use the traditional division into polychaetes (almost all marine), oligochaetes (which include earthworms) and leech-like species. Cladistic research since 1997 has radically changed this scheme, viewing leeches as a sub-group of oligochaetes and oligochaetes as a sub-group of polychaetes. In addition, the Pogonophora, Echiura and Sipuncula, previously regarded as separate phyla, are now regarded as sub-groups of polycha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
