|
Agassizodus
''Agassizodus'' is an extinct genus of eugeneodont holocephalan from the Carboniferous. It belongs to the family Helicoprionidae, which is sometimes called Agassizodontidae. Like other members of its family, it possessed a symphyseal tooth whorl, which was likely present at the tip of the lower jaw and associated with lateral crushing toothplates. The type species, ''A. variabilis'', was originally named ''Lophodus variabilis'' until the name "Lophodus" was determined to be preoccupied. ''A. variabilis'' was originally based on tooth fragments from the Pennsylvanian of Illinois, but the authors who named the genus (St. John and Worthen, 1875) also referred a massive jaw from Osage County, Kansas Osage County (county code OS) is a county located in the U.S. state of Kansas. As of the 2020 census, the county population was 15,766. Its county seat is Lyndon, and its most populous city is Osage City. The county was originally organized i .... The Osage jaw shared some simi ... [...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] |
Helicoprionidae
The Helicoprionidae, also known as the Agassizodontidae are an extinct, poorly known family of bizarre holocephalids within the poorly understood order Eugeneodontida. Members of the Helicoprionidae possessed a unique "tooth-whorl" on the symphysis of the lower jaw and pectoral fins supported by long radials. The closest living relatives of the Helicoprionidae and all other eugeneodontids are the ratfishes. The anatomy of the tooth-whorl differed amongst genus and species, some possessing complete spirals (such as those of ''Helicoprion ''Helicoprion'' is an extinct genus of shark-like eugeneodont fish. Almost all fossil specimens are of spirally arranged clusters of the individuals' teeth, called "tooth whorls", which in life were embedded in the lower jaw. As with most extin ...''), others possessing halved spirals (seen in '' Parahelicoprion''), and some with wedged half-spirals (seen in '' Sarcoprion''). Each tooth-whorl is thought to be adapted to a different type of p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Agassizodontidae
The Helicoprionidae, also known as the Agassizodontidae are an extinct, poorly known family of bizarre holocephalids within the poorly understood order Eugeneodontida. Members of the Helicoprionidae possessed a unique "tooth-whorl" on the symphysis of the lower jaw and pectoral fins supported by long radials. The closest living relatives of the Helicoprionidae and all other eugeneodontids are the ratfishes. The anatomy of the tooth-whorl differed amongst genus and species, some possessing complete spirals (such as those of ''Helicoprion''), others possessing halved spirals (seen in ''Parahelicoprion ''Parahelicoprion'' is an extinct genus of shark-like eugeneodontid holocephalids from the Permian of the Ural Mountains (Russia) and Copacabana Formation, Bolivia. The genus name, from "nearly coiled saw" in Greek, directly refers to ''Helico ...''), and some with wedged half-spirals (seen in '' Sarcoprion''). Each tooth-whorl is thought to be adapted to a different type of pre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eugeneodontida
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] |
Holocephali
Holocephali ("complete heads"), sometimes given the term Euchondrocephali, is a subclass of cartilaginous fish in the class Chondrichthyes. The earliest fossils are of teeth and come from the Devonian period. Little is known about these primitive forms, and the only surviving group in the subclass is the order Chimaeriformes. Chimaeriformes, commonly known as chimaeras, includes the rat fishes in the genus '' Chimaera'', and the elephant fishes in the genus ''Callorhinchus''. These fishes move by using sweeping movements of their large pectoral fins. They are deep sea fish with slender tails, living close to the seabed to feed on benthic invertebrates. They lack a stomach, their food moving directly into the intestine. Extinct holocephalans were much more diverse in lifestyles, including shark-like predatory forms and slow, durophagous fish. Characteristics Members of this taxon preserve today some features of elasmobranch life in Paleozoic times, though in other respects th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 ''Carboniferous'' means "coal-bearing", from the Latin '' carbō'' ("coal") and '' ferō'' ("bear, carry"), and refers to the many coal beds formed globally during that time. The first of the modern 'system' names, it was coined by geologists William Conybeare and William Phillips in 1822, based on a study of the British rock succession. The Carboniferous is often treated in North America as two geological periods, the earlier Mississippian and the later Pennsylvanian. Terrestrial animal life was well established by the Carboniferous Period. Tetrapods (four limbed vertebrates), which had originated from lobe-finned fish during the preceding Devonian, became pentadactylous in and diversified during the Carboniferous, including early amphibian line ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Listracanthus Hystrix
''Listracanthus'' is a genus of extinct chondrichthyan with uncertain affinities. Species of ''Listracanthus'' are known primarily from their tremendous, feather-like denticles, which range up to four inches in length. The denticles had a large main spine, from which secondary spines emanate from the sides, like the barbs of a feather or a comb. ''Listracanthus'' first appeared in late Carboniferous strata in North America, and eventually disappear from the fossil record some time during the Early Triassic. The appearance of these sharks are largely unknown. However, author and illustrator Ray Troll mentions in his book, ''Sharkabet'', about how paleontologist Rainer Zangerl once discovered a large shale slab containing a long, eel-like fish covered in long, spine-like denticles characteristic of the genus, only to have it dry out and crumble into dust. As such, according to Zangerl's account, Troll reconstructs ''Listracanthus'' as resembling a tremendous, fiercely bristle ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pennsylvanian (geology)
The Pennsylvanian ( , also known as Upper Carboniferous or Late Carboniferous) is, in the International Commission on Stratigraphy, ICS geologic timescale, the younger of two period (geology), subperiods (or upper of two system (stratigraphy), subsystems) of the Carboniferous Period. It lasted from roughly . As with most other geochronology, geochronologic units, the stratum, rock beds that define the Pennsylvanian are well identified, but the exact date of the start and end are uncertain by a few hundred thousand years. The Pennsylvanian is named after the U.S. state of Pennsylvania, where the coal-productive beds of this age are widespread. The division between Pennsylvanian and Mississippian (geology), Mississippian comes from North American stratigraphy. In North America, where the early Carboniferous beds are primarily marine limestones, the Pennsylvanian was in the past treated as a full-fledged geologic period between the Mississippian and the Permian. In parts of Europe, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Illinois
Illinois ( ) is a U.S. state, state in the Midwestern United States, Midwestern United States. Its largest metropolitan areas include the Chicago metropolitan area, and the Metro East section, of Greater St. Louis. Other smaller metropolitan areas include, Peoria metropolitan area, Illinois, Peoria and Rockford metropolitan area, Illinois, Rockford, as well Springfield, Illinois, Springfield, its capital. Of the fifty U.S. states, Illinois has the List of U.S. states and territories by GDP, fifth-largest gross domestic product (GDP), the List of U.S. states and territories by population, sixth-largest population, and the List of U.S. states and territories by area, 25th-largest land area. Illinois has a highly diverse Economy of Illinois, economy, with the global city of Chicago in the northeast, major industrial and agricultural productivity, agricultural hubs in the north and center, and natural resources such as coal, timber, and petroleum in the south. Owing to its centr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Osage County, Kansas
Osage County (county code OS) is a County (United States), county located in the U.S. state of Kansas. As of the 2020 United States Census, 2020 census, the county population was 15,766. Its county seat is Lyndon, Kansas, Lyndon, and its most populous city is Osage City, Kansas, Osage City. The county was originally organized in 1855 as Weller County, and was renamed in 1859 after the Osage Nation, Osage Native American Tribe. History Early history For many millennia, the Great Plains of North America was inhabited by nomadic Native Americans in the United States, Native Americans. From the 16th century to 18th century, the Kingdom of France claimed ownership of large parts of North America. In 1762, after the French and Indian War, France secretly ceded New France to Spain, per the Treaty of Fontainebleau (1762), Treaty of Fontainebleau. 19th century In 1802, Spain returned most of the land to France but keeping title to about 7,500 square miles. In 1803, most of the land f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
