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Naraoia
''Naraoia'' is a genus of small to average size (about 2-4½ cm long) marine arthropods within the family Naraoiidae, that lived from the early Cambrian to the late Silurian period. The species are characterized by a large alimentary system and sideways oriented antennas. Etymology The name is derived from Narao, the name of a group of small lakes in Cataract Brook canyon, above Hector on the Canadian Pacific Railway, British Columbia, Canada.Walcott, C.D. Middle Cambrian Branchiopoda, Malacostraca, Trilobita, and Merostomata. In: Cambrian Geology and Paleontology II. Smithsonian. 1914. s:Cambrian Geology and Paleontology/Volume 2/Middle Cambrian Branchiopoda, Malacostraca, Trilobita, and Merostomata History of the classification When the fossil was first discovered in Canada's Burgess Shale, it was believed to be a crustacean, such was the difference between this and other trilobites. Its continuous shield hid most of its structure, interfering with proper classification. Wh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Naraoia Walcott Cambrian Geology And Paleontology II Plate 28
''Naraoia'' is a genus of small to average size (about 2-4½ cm long) marine arthropods within the family Naraoiidae, that lived from the early Cambrian to the late Silurian period. The species are characterized by a large alimentary system and sideways oriented antennas. Etymology The name is derived from Narao, the name of a group of small lakes in Cataract Brook canyon, above Hector on the Canadian Pacific Railway, British Columbia, Canada.Walcott, C.D. Middle Cambrian Branchiopoda, Malacostraca, Trilobita, and Merostomata. In: Cambrian Geology and Paleontology II. Smithsonian. 1914. s:Cambrian Geology and Paleontology/Volume 2/Middle Cambrian Branchiopoda, Malacostraca, Trilobita, and Merostomata History of the classification When the fossil was first discovered in Canada's Burgess Shale, it was believed to be a crustacean, such was the difference between this and other trilobites. Its continuous shield hid most of its structure, interfering with proper classification. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Naraoiidae
Naraoiidae is a family, of extinct, soft-shelled trilobite-like arthropods, that belongs to the order Nectaspida. Species included in the Naraoiidae are known from the second half of the Lower Cambrian to the end of the Upper Silurian. The total number of collection sites is limited and distributed over a vast period of time: Maotianshan Shale and Balang Formation (China), Burgess Shale and Bertie Formation (Canada), the Šárka Formation (Czech Republic), Emu Bay Shale (Australia), Idaho and Utah (USA). This is probably due to the rare occurrence of the right circumstances for soft tissue preservation, needed for these non-calcified exoskeletons. Ecology Naraoiids probably were deposit feeders (''Naraoia'' and ''Pseudonaraoia''), predators or scavengers (''Misszhouia''), living on the sea floor. Description The species of the family ''Naraoiidae'' are almost flat (dorso-ventrally). The upper (or dorsal) side of the body consists of a non-calcified transversely oval or se ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Misszhouia
''Misszhouia'' is a genus of small to average sized (up to long) marine arthropods within the Naraoiidae family, that lived during the early Cambrian period. The only species presently known is ''Misszhouia longicaudata'' (the genus is monotypic) and the holotype was discovered in 1984. Etymology ''Misszhouia'' was named after "Miss Zhou" (Zhou Guiqin), to honour her for her skilled preparation of Chengjiang fossils. Description ''Misszhouia longicaudata'' is almost flat (dorso-ventrally). The upper (or dorsal) side of the body consists of a non-calcified headshield ( cephalon) and tailshield (pygidium) without body segments between. The body is narrowed at the articulation between cephalon and pygidium. The long many-segmented antennae are directed forward. There are no eyes. The gut has a relatively small diameter, and there are four pairs of relatively small digestive sacs (or caeca) in the cephalon only, and no branches towards the edge of the cephalon (unlike ''Nar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Misszhouia Longicaudata 2
''Misszhouia'' is a genus of small to average sized (up to long) marine arthropods within the Naraoiidae family, that lived during the early Cambrian period. The only species presently known is ''Misszhouia longicaudata'' (the genus is monotypic) and the holotype was discovered in 1984. Etymology ''Misszhouia'' was named after "Miss Zhou" (Zhou Guiqin), to honour her for her skilled preparation of Chengjiang fossils. Description ''Misszhouia longicaudata'' is almost flat (dorso-ventrally). The upper (or dorsal) side of the body consists of a non-calcified headshield ( cephalon) and tailshield (pygidium) without body segments between. The body is narrowed at the articulation between cephalon and pygidium. The long many-segmented antennae are directed forward. There are no eyes. The gut has a relatively small diameter, and there are four pairs of relatively small digestive sacs (or caeca) in the cephalon only, and no branches towards the edge of the cephalon (unlike ''Na ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nektaspida
Nektaspida (also called Naraoiida, Nektaspia and Nectaspida) is an extinct order of non- mineralised artiopodan arthropods. They are known from the mid-Cambrian to the upper Silurian. Originally classified as trilobites, which they superficially resemble, they are now placed as close relatives as members of the Trilobitomorpha within Artiopoda. The order is divided into three major families; Emucarididae, Liwiidae, and Naraoiidae. Naming history and taxonomic placement The order was originally proposed by Raymond in 1920 as Nektaspia. Størmer corrected it to Nectaspida for the 1959 ''Treatise on Invertebrate Paleontology'' to conform with the names of the other trilobite orders. Whittington described it in 1985 with the spelling Nektaspida; the revised 1997 Treatise by Raymond and Fortey uses this spelling, as do other modern works. Whittington (1985) placed the order in the Trilobita. Cotton & Braddy (2000) place it in a new "Trilobite clade" containing the Trilobita, recogni ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wheeler Shale
The Wheeler Shale (named by Charles Walcott) is a Cambrian ( 507 Ma) fossil locality world-famous for prolific agnostid and ''Elrathia kingii'' trilobite remains (even though many areas are barren of fossils) and represents a Konzentrat-Lagerstätte. Varied soft bodied organisms are locally preserved, a fauna (including ''Naraoia'', ''Wiwaxia'' and ''Hallucigenia'') and preservation style (carbonaceous film) normally associated with the more famous Burgess Shale. As such, the Wheeler Shale also represents a Konservat-Lagerstätten. Together with the Marjum Formation and lower Weeks Formation, the Wheeler Shale forms of limestone and shale exposed in one of the thickest, most fossiliferous and best exposed sequences of Middle Cambrian rocks in North America. At the type locality of Wheeler Amphitheater, House Range, Millard County, western Utah, the Wheeler Shale consists of a heterogeneous succession of highly calcareous shale, shaley limestone, mudstone and thi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
