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Caseodontoidea
The Eugeneodontida is an extinct and poorly known order of cartilaginous fishes. They possessed "tooth-whorls" on the symphysis of either the lower or both jaws and pectoral fins supported by long radials. They probably lacked pelvic fins and anal fins. The palatoquadrate was either fused to the skull or reduced. Now determined to be within the Holocephali, their closest living relatives are ratfish. The eugeneodonts are named after paleontologist Eugene S. Richardson, Jr. The Eugeneodontida disappeared in the Early Triassic. Members of the Eugeneodontida are further classified into different families, the most well-preserved members that have been discovered are commonly placed within the families Helicoprionidae ("spiral saws"), and Edestidae ("those which devour"), the former containing the genera ''Helicoprion'', '' Sarcoprion'', and '' Parahelicoprion'', and the latter containing the genera '' Edestus'', ''Lestrodus'', and '' Metaxyacanthus''. All eugeneodonts are thought ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Caseodontoidea
The Eugeneodontida is an extinct and poorly known order of cartilaginous fishes. They possessed "tooth-whorls" on the symphysis of either the lower or both jaws and pectoral fins supported by long radials. They probably lacked pelvic fins and anal fins. The palatoquadrate was either fused to the skull or reduced. Now determined to be within the Holocephali, their closest living relatives are ratfish. The eugeneodonts are named after paleontologist Eugene S. Richardson, Jr. The Eugeneodontida disappeared in the Early Triassic. Members of the Eugeneodontida are further classified into different families, the most well-preserved members that have been discovered are commonly placed within the families Helicoprionidae ("spiral saws"), and Edestidae ("those which devour"), the former containing the genera ''Helicoprion'', '' Sarcoprion'', and '' Parahelicoprion'', and the latter containing the genera '' Edestus'', ''Lestrodus'', and '' Metaxyacanthus''. All eugeneodonts are thought ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Campodus
''Campodus'' is an extinct genus of eugeneodont holocephalans from the Carboniferous. Likely one of the earliest and most basal caseodontoids, it can be characterized by its broad, ridge-ornamented crushing teeth made of various types of dentine. The type species, ''C. agassizianus'', was originally described in 1844 based on a small number of teeth from the Namurian of Belgium. Additional fossils have been referred to the genus. These include Belgian specimens referred by Lohest (1884), fossils from Missouri referred by Zangerl (1981), and symphyseal tooth-whorls from Nebraska and Kansas referred by Eastman (1902). The tooth whorls were given their own species, ''C. variabilis''. They shared some similarity to a massive "'' Agassizodus''" jaw apparatus found in Osage, Kansas and described by St. John & Worthen (1875). This has led some authors to the conclusion that ''Agassizodus'' and ''Campodus'' were synonyms. However, others note that clearly identifiable ''Campodus'' t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Late 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, where rocks from this period were first studied. The first significant adaptive radiation of life on dry land occurred during the Devonian. Free-sporing vascular plants began to spread across dry land, forming extensive forests which covered the continents. By the middle of the Devonian, several groups of plants had evolved leaves and true roots, and by the end of the period the first seed-bearing plants appeared. The arthropod groups of myriapods, arachnids and hexapods also became well-established early in this period, after starting their expansion to land at least from the Ordovician period. Fish reached substantial diversity during this time, leading the Devonian to often be dubbed the Age of Fishes. The placoderms began dominating al ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Incertae Sedis
' () or ''problematica'' is a term used for a taxonomic group where its broader relationships are unknown or undefined. Alternatively, such groups are frequently referred to as "enigmatic taxa". In the system of open nomenclature, uncertainty at specific taxonomic levels is indicated by ' (of uncertain family), ' (of uncertain suborder), ' (of uncertain order) and similar terms. Examples *The fossil plant '' Paradinandra suecica'' could not be assigned to any family, but was placed ''incertae sedis'' within the order Ericales when described in 2001. * The fossil ''Gluteus minimus'', described in 1975, could not be assigned to any known animal phylum. The genus is therefore ''incertae sedis'' within the kingdom Animalia. * While it was unclear to which order the New World vultures (family Cathartidae) should be assigned, they were placed in Aves ''incertae sedis''. It was later agreed to place them in a separate order, Cathartiformes. * Bocage's longbill, ''Motacilla bocagii' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bobbodus
''Bobbodus'' is an extinct genus of eugeneodont shark from the Carboniferous and Permian periods. ''B. schaefferi'' is the type species and is known from three specimens, all from what was the eastern coast of the Panthallasic Ocean. They were found in the Kasimovian of Iowa, Gzhelian of Nebraska, Asselian of Kansas. Specimens of this species show the partial upper and lower dentition, the palatoquadrate, and gill arch. ''B. xerxesi'' is known from a single tooth found in Wuchiapingian-aged deposits in the Baghuk Mountains of central Iran Iran, officially the Islamic Republic of Iran, and also called Persia, is a country located in Western Asia. It is bordered by Iraq and Turkey to the west, by Azerbaijan and Armenia to the northwest, by the Caspian Sea and Turkmeni .... It is named for Xerxes, a famous Archaemenid ruler from the area whose monuments impressed the first author of the paper describing it.Hampe, O., Hairapetian, V., Dorka, M., Witzmann, F., Akb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Romerodus
''Romerodus'' is an extinct genus of eugeneodontid holocephalian from the Carboniferous of North America. Fossils have been found in Nebraska Nebraska () is a state in the Midwestern region of the United States. It is bordered by South Dakota to the north; Iowa to the east and Missouri to the southeast, both across the Missouri River; Kansas to the south; Colorado to the southwe .... References Caseodontidae Animals described in 1981 {{paleo-cartilaginous-fish-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ornithoprion
''Ornithoprion'' is an extinct genus of eugeneodont holocephalan closely related to '' Caseodus.'' It lived in the Moscovian stage of the Carboniferous The Carboniferous ( ) is a geologic period and system of the Paleozoic that spans 60 million years from the end of the Devonian Period million years ago ( Mya), to the beginning of the Permian Period, million years ago. The name ''Carbonifero ... from 315.2 to 307 million years ago. Various species had an elongated lower jaw. The discovery and description of ''Ornithoprion'' helped establish many aspects of eugeneodont skull anatomy, which previously could only be gleaned from tooth data. References Carboniferous fish of North America Carboniferous cartilaginous fish Prehistoric cartilaginous fish genera {{Paleo-cartilaginous-fish-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fadenia
''Fadenia'' is an extinct genus of eugeneodontid holocephalian chondrichthyan from the Carboniferous Period of Missouri (United States), the Permian period of Greenland, and the Early Triassic epoch of Greenland and Sulphur Mountain Formation of British Columbia, Canada. Eugeneodontida are an extinct order of Chondrichthyes. They are characterized by the presence of tooth whorls. They include iconic genera, such as ''Helicoprion'' (buzz-saw shark), '' Ornithoprion'', '' Edestus'' or '' Caseodus''. ''Fadenia'' is one of the few eugeneodontid genera that survived the end-Permian mass extinction event. It is one of the last surviving genera of this clade. It could reach about in length. The first fossils of Fadenia were discovered and written about in the periodical Meddelelser om Grønland in 1932 by the Danish vertebrate palaeontologist Eigil Nielsen after studying the Upper Permian beds of Cape Stosch, in the fjord of Godthab Gulf in King Christian X Land, Greenland. He had ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
