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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] |
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 ... [...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. ''W. walcottana'' and ''W. cranbrookense'' are the only known species in this genus. 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 outline of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Andalusiana
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 Holmi ... [...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. Olenellina are arguably the earliest trilobites in the fossil record as members of Redlichiina, although Ptychopariida and Eodiscina follow soon after. The suborder died out when the Lower Cambrian 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 Trilobite#Dorsal sutures, 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), Nevad ... [...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] |
Laudonia
''Laudonia'' is an extinct genus of trilobites that 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 The Cambrian ( ) is the first geological period of the Paleozoic Era, and the Phanerozoic Eon. The Cambrian lasted 51.95 million years from the end of the preceding Ediacaran period 538.8 Ma (million years ago) to the beginning of the Ordovici .... There are currently two named species assigned to it. Distribution * ''L. bispinata'' has been collected from the Early Cambrian of Alberta ( Lower ''Olenellus'' zone, Mural Formation, Mumm Peak Section, immediately west of Mumm Peak and north of Mount Robson Provincial Park, near Mural Glacier) and of British Columbia (Cinnamon Peak-Whitehorn Mtn. Section: Dyeran) Canada.W. H. Fritz. 1992. Walcott's Lower Cambrian Olenellid trilobite collection 61k, Mount Robson Area, Canadian Rocky Mountains. Geological Survey of ... [...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 km. The park is located entir ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
