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List Of Prehistoric Jawless Fish
This list of prehistoric jawless fish is an attempt to create a comprehensive listing of all genera from the fossil record that have ever been considered to be jawless fish, excluding purely vernacular terms. The list includes all commonly accepted genera, but also genera that are now considered invalid, doubtful (''nomina dubia''), or were not formally published (''nomina nuda''), as well as junior synonyms of more established names, and genera that are no longer considered agnathans. Modern forms are excluded from this list. Naming conventions and terminology Naming conventions and terminology follow the International Code of Zoological Nomenclature. Technical terms used include: * Junior synonym: A name which describes the same taxon as a previously published name. If two or more genera are formally designated and the type specimens are later assigned to the same genus, the first to be published (in chronological order) is the senior synonym, and all other instances are junior s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arandaspis Prionotolepis
''Arandaspis prionotolepis'' is an extinct species of jawless fish that lived in the Ordovician period, about 480 to 470 million years ago. Its remains were found in the Stairway Sandstone near Alice Springs, Australia in 1959, but it was not determined that they were the oldest known vertebrates until the late 1960s. ''Arandaspis'' is named after a local Aboriginal tribe, the Aranda (now currently called Arrernte). Description ''Arandaspis'' was about long, with a streamlined body covered in rows of knobbly armoured scutes. The front of the body and the head were protected by hard plates with openings for the eyes, nostrils and gills. It probably was a filter-feeder. It had no fins; its only method of propulsion was the use of its vertically flattened tail. As a result, it probably swam in a fashion similar to a modern tadpole. See also * ''Astraspis'' * ''Sacabambaspis ''Sacabambaspis'' is an extinct genus of jawless fish that lived in the Ordovician period. ''Sacab ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aserotaspis
''Aserotaspis'' is an extinct genus of jawless fish which existed in what is now northern Canada Canada is a country in North America. Its ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, covering over , making it the world's second-largest country by tot ...."A New Agnathan from the Lower Devonian of Arctic Canada, and a review of the Tessellated Heterostracans" by D.K. Elliott and E.J. Loeffler, 1988. It was first named by Dineley and Loeffler in 1976, and contains the species ''Aserotaspis canadensis''. References [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ariaspis
''Ariaspis'' is an extinct genus of cyathaspidiform heterostracan agnathan. Fossils are found in marine strata of Canada and Europe from the late Silurian period until its extinction during the Early Devonian The Devonian ( ) is a geologic period and system of the Paleozoic era, spanning 60.3 million years from the end of the Silurian, million years ago (Mya), to the beginning of the Carboniferous, Mya. It is named after Devon, England, whe .... A new species, ''A. arctata'', was described by David K. Elliott and Sandra Swift in 2010. References Cyathaspidiformes genera Devonian jawless fish Silurian jawless fish Silurian first appearances Early Devonian genus extinctions Cyathaspidida Silurian fish of North America Silurian fish of Europe Paleozoic life of the Northwest Territories {{Pteraspidomorphi-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Archipelepis
''Archipelepis'' is a genus of extinct thelodont agnathans, and are the most primitive recognized thelodonts of which whole body fossils are known.Wilson, Mark VH, and Tiiu Märss. "Thelodont phylogeny revisited, with inclusion of key scale-based taxa." Estonian Journal of Earth Sciences 58.4 (2009): 297œ310/ref> Fossils of bodies and scales are currently known from Late Telychian to Wenlock-aged marine strata of northern Canada.Soehn, K. L., Märss, T., Caldwell, M. W. & Wilson, M. V. H., 2001: New and biostratigraphically useful thelodonts from the Silurian of the Mackenzie Mountains, Northwest Territories, Canada. Journal of Vertebrate Paleontology, 21: 651-65/ref> Anatomy Both species have similar body morphology, in that both resembled tadpoles with forked tails. Scale morphology differs in that ''A. bifurcata'' has forked scales with two prong-like spires, and that ''A. turbinata'' has bulbous, pointed scales that resemble upside-down spinning top A spinning top, or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arandaspis
''Arandaspis prionotolepis'' is an extinct species of jawless fish that lived in the Ordovician period, about 480 to 470 million years ago. Its remains were found in the Stairway Sandstone near Alice Springs, Australia in 1959, but it was not determined that they were the oldest known vertebrates until the late 1960s. ''Arandaspis'' is named after a local Aboriginal tribe, the Aranda (now currently called Arrernte). Description ''Arandaspis'' was about long, with a streamlined body covered in rows of knobbly armoured scutes. The front of the body and the head were protected by hard plates with openings for the eyes, nostrils and gills. It probably was a filter-feeder. It had no fins; its only method of propulsion was the use of its vertically flattened tail. As a result, it probably swam in a fashion similar to a modern tadpole. See also * ''Astraspis'' * ''Sacabambaspis ''Sacabambaspis'' is an extinct genus of jawless fish that lived in the Ordovician period. ''S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Apedolepis
''Apedolepis'' (meaning "flat scale", from Greek ἄπεδοςi, ''apedos'', meaning 'even', 'flat', or 'level' and λεπίς, meaning 'scale') was an extinct genus of early jawless fish known from the Ordovician Stokes Formation of central Australia Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, sma .... All existing material was collected in the Areyonga Creek section of the eastern Gardiner Range. ''Apedolepis'' is known solely from scales, with the type specimen (CPC 33630) consisting of a single scale. References Ordovician jawless fish Prehistoric fish of Australia Prehistoric jawless fish genera {{ordovician-animal-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
