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Fritzolenellus
''Fritzolenellus'' is an extinct genus from a well-known class of fossil marine arthropods, the trilobites, with three known species. It lived during the early part of the Botomian stage, which lasted from approximately 524 to 518.5 million years ago. This faunal stage was part of the Cambrian Period. ''Fritzolenellus'' occurred in parts of the paleocontinent Laurentia in what are now Northwestern Canada, Northwestern Scotland, and North-Greenland. Taxonomy ''Fritzolenellus'' is the genus closest to the common ancestor of ''Mummaspis'', ''Laudonia'', the Biceratopsinae and the Bristoliinae. This clade is the sister group '' Wanneria walcottana'' and of the Holmiidae. Etymology The generic name is a combination of the genus ''Olenellus'', to which these species were originally assigned, and a reference to William Henry Fritz (1928-2009), a paleontologist who worked on olenelloid trilobites. The species names have the following derivation. *''lapworthi'' is named in honor of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fritzolenellus Truemani USNM PAL 60087
''Fritzolenellus'' is an extinct genus from a well-known class of fossil marine arthropods, the trilobites, with three known species. It lived during the early part of the Botomian stage, which lasted from approximately 524 to 518.5 million years ago. This faunal stage was part of the Cambrian Period. ''Fritzolenellus'' occurred in parts of the paleocontinent Laurentia in what are now Northwestern Canada, Northwestern Scotland, and North-Greenland. Taxonomy ''Fritzolenellus'' is the genus closest to the common ancestor of ''Mummaspis'', ''Laudonia'', the Biceratopsinae and the Bristoliinae. This clade is the sister group '' Wanneria walcottana'' and of the Holmiidae. Etymology The generic name is a combination of the genus ''Olenellus'', to which these species were originally assigned, and a reference to William Henry Fritz (1928-2009), a paleontologist who worked on olenelloid trilobites. The species names have the following derivation. *''lapworthi'' is named in honor of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Olenellus
''Olenellus'' is an extinct genus of redlichiid trilobites, with species of average size (about long). It lived during the Botomian and Toyonian stages (''Olenellus''-zone), , in what is currently North-America, part of the palaeocontinent Laurentia. Etymology ''Olenellus fowleri'' was named in honor of Ed Fowler''Olenellus'' means small ''Olenus'', after a genus belonging to the Ptychopariida, to which the type species ''O. thompsoni'' was originally assigned. The name Olenus refers to a mythological figure who was turned to stone by the gods. The names of the species have the following derivations. * ''agellus'' comes from the Latin word for field or hamlet. * ''chiefensis'' refers to the Chief Range, which includes the Ruin Wash section, that holds the last of the Olenellina. * ''fowleri'' was named in honor of Ed Fowler, whose quarrying skills exposed the type locality of this species. * ''getzi'' is called afteNoah L. Getz on whose Lancaster estate several ''Olene ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Olenelloidea
The Olenelloidea are a superfamily of trilobites, a group of extinct marine arthropods. They lived during the late Lower Cambrian and species occurred on all paleocontinents. Taxonomy Palmer and Repina assigned '' Gabriellus'' and ''Callavia'' to the Olenelloidea, but the ocular lobes in these two genera circumscribe the entire lateral border of the frontal lobe of the glabella, and thus, do not belong to this superfamily, but to the Judomioidea. Geyer assigned '' Cambropallas'' to the Olenelloidea, but it lacks the diagnostic features and appears to be closely related to '' Andalusiana'', and is now considered to be an advanced member of the Nevadioidea. Distribution In western Laurentia Fallotaspididae and Archaeaspididae proceed the first Olenelloidea. The Holmiidae occur at the late Atdabanian, and are contemporary with the Nevadioidea. They are followed by Biceratopsidae and Olenellidae. Description As with most early trilobites, the Olenelloidea have an almost ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Olenellina
Olenellina is a suborder of the order Redlichiida of trilobites that occurs about halfway during the Lower Cambrian, at the start of the stage called the Atdabanian. The earliest trilobites in the fossil record are arguably Olenellina, although the earliest Redlichiina and Eodiscina follow quickly. The suborder died out when the Lower passed into the Middle Cambrian, at the end of the stage called Toyonian. A feature uniting the Olenellina is the lack of rupture lines (or sutures) in the headshield, which in other trilobites assist the periodic moulting (or ecdysis), associated with arthropod growth. Some derived trilobites have lost facial sutures again (some Eodiscina, all Agnostina, and a few Phacopina), but all of these are blind, while all Olenellina have eyes. Taxonomy The suborder contains four superfamilies: Olenelloidea (with 3 families and 5 stemgroup genera), Judomioidea (with 1 family and 3 stemgroup genera), Nevadioidea, and Fallotaspidoidea (with 3 familie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wanneria
''Wanneria'' is an extinct genus from a well-known class of fossil marine arthropods, the trilobites. It lived during the later part of the Botomian stage, which lasted from approximately 524 to 518.5 million years ago. This faunal stage was part of the Cambrian Period. ''Wanneria walcottana'' is the only known species in this genus (i.e. the genus is monotypic). Description As with most early trilobites, ''Wanneria walcottana'' has an almost flat exoskeleton, that is only thinly calcified, and has crescent-shaped eye ridges. As part of the Olenellina suborder, ''Wanneria'' lacks dorsal sutures. Like all other members of the Olenelloidea superfamily, the eye-ridges spring from the back of the frontal lobe (L4) of the central area of the cephalon, that is called glabella. The dorsal exoskeleton of ''Wanneria'' has an inverted egg shaped outline, approximately 1½ times longer than wide, ignoring the pleural spines, and is at its widest at the back of the cephalon. The horizontal ... [...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] |
Paleocontinent
A paleocontinent or palaeocontinent is a distinct area of continental crust that existed as a major landmass in the geological past. There have been many different landmasses throughout Earth's time. They range in sizes, some are just a collection of small microcontinents while others are large conglomerates of crust. As time progresses and sea levels rise and fall more crust can be exposed making way for larger landmasses. The continents of the past shaped the evolution of organisms on Earth and contributed to the climate of the globe as well. As landmasses break apart, species are separated and those that were once the same now have evolved to their new climate. The constant movement of these landmasses greatly determines the distribution of organisms on Earth's surface. This is evident with how similar fossils are found on completely separate continents. Also, as continents move, mountain building events (orogenies) occur, causing a shift in the global climate as new rock is expo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trilobite Zone
Trilobites are used as index fossils to subdivide the Cambrian period. Assemblages of trilobites define trilobite zones. The ''Olenellus''-zone has traditionally marked the top of the Lower Cambrian, and is followed by the '' Eokochaspis'' zone. The last two zones of the Middle Cambrian are the '' Bathyuriscus– Elrathina''-zone (contemporaneous with the Burgess Shale) and the subsequent '' Bolaspidella''-zone (starting at the base of the Drumian stage). These are overlain by the lowermost Upper Cambrian ''Cedaria''-zone. Alternative zoning names place the Burgess Shale in the ''Peronopsis bonnerensis''-zone, which is underlain by the ''Oryctocephalus indicus''-zone (e.g. Spence Shale) and overlain (perhaps not directly) by the ''Ptychagnostus punctuosus''-zone. The lower Middle Cambrian '' Glossopleura''-zone (Spence Shale) is above the '' Albertella''-zone. The '' Elvinia''-zone is upper Cambrian. Subdivision of the ''Olenellus''-zone Recently, it has been proposed to ... [...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] |
Index Fossils
Biostratigraphy is the branch of stratigraphy which focuses on correlating and assigning relative ages of rock strata by using the fossil assemblages contained within them.Hine, Robert. “Biostratigraphy.” ''Oxford Reference: Dictionary of Biology'', 8th ed., Oxford University Press, 2019. The primary objective of biostratigraphy is ''correlation'', demonstrating that a particular horizon in one geological section represents the same period of time as another horizon at a different section. Fossils within these strata are useful because sediments of the same age can look completely different, due to local variations in the sedimentary environment. For example, one section might have been made up of clays and marls, while another has more chalky limestones. However, if the fossil species recorded are similar, the two sediments are likely to have been laid down around the same time. Ideally these fossils are used to help identify biozones, as they make up the basic biostratigrap ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Charles Lapworth
Charles Lapworth FRS FGS (20 September 1842 – 13 March 1920) was a headteacher and an English geologist who pioneered faunal analysis using index fossils and identified the Ordovician period. Biography Charles Lapworth was born at Faringdon in Berkshire (now Oxfordshire) the son of James Lapworth. His school in Galashiels in 2021 He trained as a teacher at the Culham Diocesan Training College near Abingdon, Oxfordshire. He moved to the Scottish border region, where he investigated the previously little-known fossil fauna of the area. He was headmaster of the school in Galashiels from 1864 to 1875. In 1869 he married Janet, daughter of Galashiels schoolmaster Walter Sanderson. Through mapping and innovative use of index fossil analysis, based on a sequence exposed at Dob's Linn, Lapworth showed that what was thought to be a thick sequence of Silurian rocks was in fact a much thinner series of rocks repeated by faulting and folding. He completed this pioneering resea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Holmiidae
Holmiidae is a family of trilobites, that lived during the Lower Cambrian (Atdabanian). The Holmiidae is a diverse family of eight genera containing at least 17 species. It includes some of the earliest trilobites of Baltica. Holmiidae occur throughout Baltica (Scandinavia and the eastern seaboard of the Baltic Sea) and Western Laurentia (in the Great Basin of the US and northwestern Canada), and also in Morocco. Taxonomy Hupé (1953) defined the Holmiidae as a subfamily (Holmiinae) within the Olenellidae containing ''Holmia'', ''Kjerulfia'' and ''Bondonella''. Harrington et al. (1959) excluded ''Kjerulfia'', while assigning ''Schmidtiellus'' to it. Bergström (1973) included ''Holmia'', '' Elliptocephala'', ''Esmeraldina'', ''Schmidtiellus'' and '' Wanneria''. Repina (1979) assigned ''Holmia'', ''Schmidtiellus'', ''Kjerulfia'', ''Elliptocephala'', ''Bondonella'', ''Andalusiana'' and ''Holmiella'' to the Holmiinae, that together with the monotypic Callaviinae comprised the Hol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
