Acanthorhachis
   HOME
*





Acanthorhachis
''Acanthorhachis'' is an enigmatic extinct genus of chondrichthyan from the Carboniferous period. Its name is derived from the Greek word ''acanthos'' meaning "spine" and the Greek suffix for spine, -''rhachis''. This is due to the spine-like dermal denticles and their subsidiary spines, which coated the exterior of the animal. The authors who erected this genus suggested the common name "The Spiny Spined Shark." It is closely related to ''Listracanthus''. It differs from it in the size, structure, and distribution of dermal spines. It is currently monotypic, containing only the species ''A. spinatus''. This shark is thus far only described from the British Isles. ''Acanthorhachis'' was first described from the Westphalian-aged lower coal measures of Yorkshire, England. It occurs rarely in Viséan-aged Eyam Limestone of Derbyshire, England Derbyshire ( ) is a ceremonial county in the East Midlands, England. It includes much of the Peak District National Park, the southern en ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Listracanthus
''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 Ray Troll (born March 4, 1954) is an American artist based in Ketchikan, Alaska. He is best known for his scientifically accurate and often humorous artwork. His most well-known design is "Spawn Till You Die", which has appeared in many places inc ... mentions in his book, ''Sharkabet'', about how paleontologist Rainer Zangerl once discovered a large shale slab containing a lo ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Genus
Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus comes above species and below family (taxonomy), family. In binomial nomenclature, the genus name forms the first part of the binomial species name for each species within the genus. :E.g. ''Panthera leo'' (lion) and ''Panthera onca'' (jaguar) are two species within the genus ''Panthera''. ''Panthera'' is a genus within the family Felidae. The composition of a genus is determined by taxonomy (biology), taxonomists. The standards for genus classification are not strictly codified, so different authorities often produce different classifications for genera. There are some general practices used, however, including the idea that a newly defined genus should fulfill these three criteria to be descriptively useful: # monophyly – all descendants ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Chondrichthyes
Chondrichthyes (; ) is a class that contains the cartilaginous fishes that have skeletons primarily composed of cartilage. They can be contrasted with the Osteichthyes or ''bony fishes'', which have skeletons primarily composed of bone tissue. Chondrichthyes are jawed vertebrates with paired fins, paired nares, scales, and a heart with its chambers in series. Extant chondrichthyes range in size from the 10 cm (3.9 in) finless sleeper ray to the 10 m (32 ft) whale shark. The class is divided into two subclasses: Elasmobranchii (sharks, rays, skates, and sawfish) and Holocephali ( chimaeras, sometimes called ghost sharks, which are sometimes separated into their own class). Within the infraphylum Gnathostomata, cartilaginous fishes are distinct from all other jawed vertebrates. Anatomy Skeleton The skeleton is cartilaginous. The notochord is gradually replaced by a vertebral column during development, except in Holocephali, where the notochord stays intact. In some deepwat ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Carboniferous Period
The Carboniferous ( ) is a Period (geology), geologic period and System (stratigraphy), system of the Paleozoic that spans 60 million years from the end of the Devonian Period million years ago (Myr, Mya), to the beginning of the Permian Period, million years ago. The name ''Carboniferous'' means "coal-bearing", from the Latin ''wikt:carbo#Latin, carbō'' ("coal") and ''wikt:fero#Latin, 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 (geologist), William Conybeare and William Phillips (geologist), 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 (geology), Mississippian and the later Pennsylvanian (geology), Pennsylvanian. Terrestrial animal life was well established by the Carboniferous Period. Stegocephalia, Tetrapods ( ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Greek Language
Greek ( el, label=Modern Greek, Ελληνικά, Elliniká, ; grc, Ἑλληνική, Hellēnikḗ) is an independent branch of the Indo-European family of languages, native to Greece, Cyprus, southern Italy (Calabria and Salento), southern Albania, and other regions of the Balkans, the Black Sea coast, Asia Minor, and the Eastern Mediterranean. It has the longest documented history of any Indo-European language, spanning at least 3,400 years of written records. Its writing system is the Greek alphabet, which has been used for approximately 2,800 years; previously, Greek was recorded in writing systems such as Linear B and the Cypriot syllabary. The alphabet arose from the Phoenician script and was in turn the basis of the Latin, Cyrillic, Armenian, Coptic, Gothic, and many other writing systems. The Greek language holds a very important place in the history of the Western world. Beginning with the epics of Homer, ancient Greek literature includes many works of lasting impo ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Dermal Denticles
A fish scale is a small rigid plate that grows out of the skin of a fish. The skin of most jawed fishes is covered with these protective scales, which can also provide effective camouflage through the use of reflection and colouration, as well as possible hydrodynamic advantages. The term ''scale'' derives from the Old French , meaning a shell pod or husk. Scales vary enormously in size, shape, structure, and extent, ranging from strong and rigid armour plates in fishes such as shrimpfishes and boxfishes, to microscopic or absent in fishes such as eels and anglerfishes. The morphology of a scale can be used to identify the species of fish it came from. Scales originated within the jawless ostracoderms, ancestors to all jawed fishes today. Most bony fishes are covered with the cycloid scales of salmon and carp, or the ctenoid scales of perch, or the ganoid scales of sturgeons and gars. Cartilaginous fishes (sharks and rays) are covered with placoid scales. Some species are ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


Westphalian (stage)
The Westphalian is a stage in the regional stratigraphy of northwest Europe with an age between roughly 313 and 304 Ma (million years ago). It is a subdivision of the Carboniferous system or period and the regional Silesian series. The Westphalian is named for the region of Westphalia (German: ''Westfalen'') in western Germany where strata of this age occur. The Coal Measures of England and Wales are also largely of Westphalian age though they also extend into the succeeding Stephanian. The Westphalian age is preceded by the Namurian stage/age (which corresponds to the Millstone Grit Series of Great Britain) and succeeded by the Stephanian stage/age (which corresponds to the uppermost part of the Coal Measures of Great Britain). In the official geologic timescale of the ICS, the Westphalian is placed within the Pennsylvanian epoch (318-299 Ma).F M Gradstein, J G Ogg, A G Smith et al 2004, ‘A Geologic Time Scale 2004’. The (regionally defined) Westphalian stage corres ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Yorkshire, England
Yorkshire ( ; abbreviated Yorks), formally known as the County of York, is a historic county in northern England and by far the largest in the United Kingdom. Because of its large area in comparison with other English counties, functions have been undertaken over time by its subdivisions, which have also been subject to periodic reform. Throughout these changes, Yorkshire has continued to be recognised as a geographic territory and cultural region. The name is familiar and well understood across the United Kingdom and is in common use in the media and the military, and also features in the titles of current areas of civil administration such as North Yorkshire, South Yorkshire, West Yorkshire and the East Riding of Yorkshire. Within the borders of the historic county of Yorkshire are large stretches of countryside, including the Yorkshire Dales, North York Moors and Peak District national parks. Yorkshire has been nicknamed "God's Own Country" or "God's Own County" by its ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


Viséan
The Visean, Viséan or Visian is an age in the ICS geologic timescale or a stage in the stratigraphic column. It is the second stage of the Mississippian, the lower subsystem of the Carboniferous. The Visean lasted from to Ma. It follows the Tournaisian age/stage and is followed by the Serpukhovian age/stage. Name and definitions The Viséan Stage was introduced by Belgian geologist André Dumont in 1832. Dumont named this stage after the city of Visé in Belgium's Liège Province. Before being used as an international stage, the Visean Stage was part of the (West) European regional geologic time scale, in which it followed the Tournaisian Stage and is followed by the Namurian Stage. In the North American regional scale, the Visean Stage correlates with the upper Osagean, the Meramecian and lower Chesterian stages. In the Chinese regional time scale, it correlates with the lower and middle Tatangian series.; 2006: ''Global time scale and regional stratigraphic reference sca ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


Eyam Limestone
The Eyam Limestone is a geologic formation in England. It preserves fossils dating back to the Carboniferous period. See also * List of fossiliferous stratigraphic units in England See also *Lists of fossiliferous stratigraphic units in Europe * Lists of fossiliferous stratigraphic units in the United Kingdom References * {{DEFAULTSORT:Fossiliferous stratigraphic units in England England England is a country ... References * Carboniferous System of Europe Carboniferous England Limestone formations Carboniferous southern paleotropical deposits {{England-stub ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Derbyshire
Derbyshire ( ) is a ceremonial county in the East Midlands, England. It includes much of the Peak District National Park, the southern end of the Pennine range of hills and part of the National Forest. It borders Greater Manchester to the north-west, West Yorkshire to the north, South Yorkshire to the north-east, Nottinghamshire to the east, Leicestershire to the south-east, Staffordshire to the west and south-west and Cheshire to the west. Kinder Scout, at , is the highest point and Trent Meadows, where the River Trent leaves Derbyshire, the lowest at . The north–south River Derwent is the longest river at . In 2003, the Ordnance Survey named Church Flatts Farm at Coton in the Elms, near Swadlincote, as Britain's furthest point from the sea. Derby is a unitary authority area, but remains part of the ceremonial county. The county was a lot larger than its present coverage, it once extended to the boundaries of the City of Sheffield district in South Yorkshire where it cov ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Carboniferous Cartilaginous Fish
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 lineages ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]