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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] |
Elliptocephala
''Elliptocephala'' is an extinct genus from a well-known class of fossil marine arthropods, the trilobites. It lived from the later part of the Tommotian ( upper ''Schmidtiellus mickwitzi''-zone) to the upper Botomian ( early middle ''Olenellus''-zone). ''Elliptocephala'' can easily be confused with ''Ellipsocephalus'', a trilobite genus of the Ptychopariida order. Etymology The species ''E. walcotti'' was named in honor of Charles Doolittle Walcott, a renowned early paleontologist, that described many trilobite species. Taxonomy Relations within ''Elliptocephala'' According to Lieberman ''E. sequomalus'' is an early species, close to the common ancestor of the genus. The rest of the species fall into two distinct groups. The first consists of the closely related ''E. bicensis'' and ''E. asaphoides'', with ''E. walcotti'' and twin species ''E. praenuntius'' slightly less close and ''E. mediocris'' near the basis of this group. The second group consisting of the closely re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lochmanolenellus
''Lochmanolenellus'' is an extinct genus of trilobites, fossil marine arthropods, with one small species, ''L. mexicana''. It lived during the Botomian stage (''Olenellus''-zone), 522–513 million years ago, in the South-West of the former continent of Laurentia, in what are today Mexico, and the South-Western United States. Etymology ''Lochmanolenellus'' is named in honor of C. Lochman, who initially described the fossils that are assigned to this genus, and for its likeness to ''Olenellus'' a distantly related genus. The species epithet ''mexicana'' refers to Mexico, where the first specimen was found. Taxonomy ''L. mexicana'' was first described as ''Wanneria mexicana prima''. There are however so many differences, that it is highly unlikely ''L. mexicana'' is more than distantly related. Later scholars assigned the species to ''Laudonia''. Although ''Laudonia'' is much more related than ''Wanneria'', ''L. mexicana'' must be considered an early representative of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mummaspis
''Mummaspis'' is an extinct genus from a well-known class of fossil marine arthropods, the trilobites, with five 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. Taxonomy ''Mummaspis'' is the genus closest to the common ancestor of ''Laudonia'', the Biceratopsinae and the Bristoliinae. Including the species of ''Fritzolenellus'', this clade is the sister group of ''Wanneria walcottana'' and the Holmiidae. Distribution * ''M. occidens'' was collected in the Lower Cambrian ( lower ''Olenellus''-zone) of Alberta, Canada (Mural Formation, in the talus slope immediately west of Mumm Peak, and from the middle Mural Formation, 125 m above the base of that formation, just north of the Mount Robson Provincial Park Mount Robson Provincial Park is a provincial park in the Canadian Rockies with an area of 2,249 km². The park is located ent ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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] |
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] |
Fremontella
''Fremontella'' is an extinct genus from a well-known class of fossil marine arthropods, the trilobites. It lived during the part of the Toyonian stage. This faunal stage was part of the Cambrian Period. ''Fremontella'' shares with the other genera of the Bristoliinae The Bristoliinae is an extinct subfamily of trilobites, fossil marine arthropods, with species of small to average size. Species belonging to this subfamily lived during the Botomian and Toyonian stage (''Olenellus''-zone), 522-513 million years ... subfamily, Lochmanolenellus and Bristolia conspicuous and long curved spines (called genal spines) on the headshield (or cephalon). These reach back equal to 4-5 thorax segments (measured parallel to the midline). The furrows that separate border, eye ridges, glabella and its lobes are distinct (unlike in the Biceratopsinae). The area outside of the axis (or pleural lobes) of the third segment of the thorax is enlarged, and carries large trailing spine on each side. ... [...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] |
Lancaster, Pennsylvania
Lancaster, ( ; pdc, Lengeschder) is a city in and the county seat of Lancaster County, Pennsylvania. It is one of the oldest inland cities in the United States. With a population at the 2020 census of 58,039, it ranks 11th in population among Pennsylvania's municipalities. The Lancaster metropolitan area population is 507,766, making it the 104th-largest metropolitan area in the U.S. and second-largest in the South Central Pennsylvania area. The city's primary industries include healthcare, tourism, public administration, manufacturing, and both professional and semi-professional services. Lancaster is a hub of Pennsylvania's Dutch Country. Lancaster is located southwest of Allentown and west of Philadelphia. History Originally called Hickory Town, the city was renamed after the English city of Lancaster by native John Wright. Its symbol, the red rose, is from the House of Lancaster. Lancaster was part of the 1681 Penn's Woods Charter of William Penn, and was laid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bondonella
''Bondonella'' is an extinct genus from a well-known class of fossil marine arthropods, the trilobites. It lived during the late Atdabanian stage, which lasted from 530 to 524 million years ago during the early part of the Cambrian Period 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 .... References Cambrian trilobites Fossils of Morocco {{trilobite-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neltneria
''Neltneria'' is an extinct genus from a well-known class of fossil marine arthropods, the trilobites. It lived during the late Atdabanian stage, which lasted from 530 to 524 million years ago during the early part of the Cambrian Period 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 .... References Cambrian trilobites Trilobites of Africa {{trilobite-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cladistics
Cladistics (; ) is an approach to biological classification in which organisms are categorized in groups (" clades") based on hypotheses of most recent common ancestry. The evidence for hypothesized relationships is typically shared derived characteristics ( synapomorphies'')'' that are not present in more distant groups and ancestors. However, from an empirical perspective, common ancestors are inferences based on a cladistic hypothesis of relationships of taxa whose character states can be observed. Theoretically, a last common ancestor and all its descendants constitute a (minimal) clade. Importantly, all descendants stay in their overarching ancestral clade. For example, if the terms ''worms'' or ''fishes'' were used within a ''strict'' cladistic framework, these terms would include humans. Many of these terms are normally used paraphyletically, outside of cladistics, e.g. as a 'grade', which are fruitless to precisely delineate, especially when including extinct species. R ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
