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Biceratops
''Biceratops'' is an extinct genus of olenelloid redlichiid trilobites, of average size, with the largest specimen long, not including the huge pleural spines of the 3rd segment of the thorax. It lived during the Toyonian stage (last phase of the Upper ''Olenellus''-zone), in what is today the South-Western United States. ''Biceratops'' can easily be distinguished from other members of Biceratopsidae by the absence of genal spines, in combination with effaced features of the raised axial area of the head shield (or glabella), that is bordering the two horn-like projections that carry the eyes. ''Biceratops nevadensis'' is the only known species in this genus (i.e. the genus is monotypic). Etymology The name of the genus is derived from Latin and means ‘two horned-eyes’. The species epithet refers to the US state where it was collected. Description As with most early trilobites, ''Biceratops'' has an almost flat exoskeleton, that is only thinly calcified. It also shares ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biceratopsinae
The Biceratopsinae is an extinct subfamily of redlichiid trilobites within the family Biceratopsidae, with species of small to average size. Species belonging to this subfamily lived during the Toyonian stage (Upper ''Olenellus''-zone), 516-513 million years ago, in the former continent of Laurentia, including what are today the South-Western United States and Canada. Etymology The Biceratopsinae are named for the type species '' Biceratops nevadensis''. Habitat The Biceratopsinae were probably marine bottom dweller, like all Olenellina. References Cambrian trilobites Cambrian Series 2 first appearances Cambrian Series 2 extinctions Biceratopsidae Arthropod subfamilies {{Redlichiida-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biceratopsidae
Biceratopsidae is an extinct family of redlichiid trilobites, with species of small to average size. Species of belonging to this family lived during the Toyonian stage (''Olenellus''-zone), 522–513 million years ago, in the former continent of Laurentia, including what are today the south-western United States and Canada. It contains the subfamilies Biceratopsinae and Bristoliinae. Habitat The Biceratopsidae were probably marine bottom dweller, like all Olenellina. References Olenelloidea Trilobite families Cambrian trilobites Cambrian first appearances Cambrian Series 2 extinctions {{redlichiida-stub ... [...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] |
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] |
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] |
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] |
Latin
Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power of the Roman Republic it became the dominant language in the Italian region and subsequently throughout the Roman Empire. Even after the fall of Western Rome, Latin remained the common language of international communication, science, scholarship and academia in Europe until well into the 18th century, when other regional vernaculars (including its own descendants, the Romance languages) supplanted it in common academic and political usage, and it eventually became a dead language in the modern linguistic definition. Latin is a highly inflected language, with three distinct genders (masculine, feminine, and neuter), six or seven noun cases (nominative, accusative, genitive, dative, ablative, and vocative), five declensions, four verb conjuga ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cambrian Trilobites Of North America
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] |
Redlichiida Genera
Redlichiida is an order of trilobites, a group of extinct marine arthropods. Species assigned to the order Redlichiida are among the first trilobites to appear in the fossil record, about halfway during the Lower Cambrian. Due to the difficulty to relate sediments in different areas, there remains some discussion, but among the earliest are '' Fallotaspis'' (suborder Olenellina), and ''Lemdadella'' (suborder Redlichiina), both belonging to this order. The first representatives of the orders Corynexochida and Ptychopariida also appear very early on and may prove to be even earlier than any redlichiid species. In terms of anatomical comparison, the earliest redlichiid species are probably ancestral to all other trilobite orders and share many primitive characters. The last redlichiid trilobites died out before the end of the Middle Cambrian. Description Most redlichiids are rather flat (or have low dorso-ventral convexity) and their exoskeleton typically has an oval outline, a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mesonacis
''Mesonacis'' is an extinct genus of trilobite that lived during the Botomian, found in North-America (excluding Greenland), and the United Kingdom (North-Western Scotland). Some of the species now regarded part of ''Mesonacis'', have previously been assigned to ''Angustolenellus'' or ''Olenellus (Angustolenellus)''. ''Angustolenellus'' is now regarded a junior synonym of ''Mesonacis''. Etymology ''M. vermontanus'' is named after the State of Vermont, where it was collected. ''M. bonnensis'' is called after the Bonne Bay, Newfoundland, where the species is found. ''M. eagerensis'' refers to the Eager Formation, British Columbia, in which it occurs. ''M. hamoculus'' is derived from the Latin hamus, meaning hooked, and oculus, meaning eye. Distribution ''M. vermontanus'' occurs in the middle Upper ''Olenellus''-zone of Vermont (Parker Slate, Georgia). ''M. bonnensis'' has been found in the ''Olenellus''-zone of Newfoundland, Canada (Forteau Formation, East shore of the Bonn ... [...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] |
Clark County, Nevada
Clark County is located in the U.S. state of Nevada. As of the 2020 census, the population was 2,265,461. Most of the county population resides in the Las Vegas Census County Divisions, which hold 1,771,945 people as of the 2010 Census, across . It is by far the most populous county in Nevada, and the 11th most populous county in the United States. It covers 7% of the state's land area but holds 74% of the state's population, making Nevada one of the most centralized states in the United States. History Las Vegas, the state's most populous city, has been the county seat since its establishment. The county was formed by the Nevada Legislature by splitting off a portion of Lincoln County, Nevada, Lincoln County on February 5, 1909, and was organized on July 1, 1909. The Las Vegas Valley (landform), Las Vegas Valley, a basin, includes Las Vegas and other major cities and communities such as North Las Vegas, Henderson, Nevada, Henderson, and the unincorporated community of Parad ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
