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Aïstopod
Aistopoda (Greek for "[having] not-visible feet") is an order of highly specialised snake-like stegocephalian, stegocephalians known from the Carboniferous and Cisuralian, Early Permian of Europe and North America, ranging from tiny forms only , to nearly in length. They first appear in the fossil record in the Mississippian age, Mississippian period and continue through to the Cisuralian, Early Permian. The skull is small but very specialised, with large Orbit (anatomy), orbits, and large Fenestra (anatomy), fenestrae. The primitive form ''Ophiderpeton'' has a pattern of dermal bones in the skull similar in respects to the temnospondyls. But in the advanced genus ''Phlegethontia'' the skull is very light and open, reduced to a series of struts supporting the braincase against the lower jaw, just as in Ophidia, snakes, and it is possible that the aistopods filled the same ecological niches in the Paleozoic that snakes do today. They had an extremely elongated body, with up to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lethiscus
''Lethiscus'' is the earliest known representative of the Aistopoda, a group of very specialised snake-like amphibians known from the early Carboniferous ( Mississippian). ''Lethiscus'' is known from only a single specimen from the Holkerian Stage (Middle Viséan) of the Early Carboniferous (Middle Mississippian) of Scotland, and is one of the oldest known post Devonian tetrapods. Despite its very early date, it was already a highly advanced animal. The skull is specialised and light, very like that of '' Ophiderpeton'', with the orbits, far forward, and the cheek region unossified (lacking bone). There are approximately 30 closely spaced teeth on the maxilla and dentary, and a sutural pattern of the skull closely resembles that of the Late Carboniferous aïstopod '' Oestocephalus''. There is no trace of limbs. However, unlike later members of the aïstopod lineage, the vertebrae still possess intercentra, and the pleurocentra are large. ''Lethiscus'' is the only represe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Andersonerpeton
''Andersonerpeton'' is an extinct genus of aïstopod from the Bashkirian (early Pennsylvanian) of Nova Scotia, Canada. It is known from a single jaw, which shares an unusual combination of features from both other aistopods and from stem-tetrapod tetrapodomorph fish. As a result, ''Andersonerpeton'' is significant for supporting a new classification scheme which states that aistopods evolved much earlier than previously expected. The genus contains a single species, ''A. longidentatum'', which was previously believed to have been a species of the microsaur ''Hylerpeton.'' History The type species, ''A. longidentatum'', was initially described by John William Dawson on the basis of RM 2.1129, a left mandible. This fossil hailed from the Joggins fossil cliffs, a site in Nova Scotia famous for fossil deposits dated to the Bashkirian, the first stage of the Pennsylvanian subperiod of the Carboniferous period. ''A. longidentatum'' was originally named ''Hylerpeton longidentatum'', ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phlegethontia
''Phlegethontia'' is an extinct genus of aïstopod stegocephalians from the Carboniferous and Permian periods of Europe and North America. It was about long, and possessed a lightly built skull with many openings, unlike some earlier relatives. ''"Dolichosoma" longissima'', named by Antonin Fritsch in 1875, has been reassigned to the genus ''Phlegethontia'' and is now considered to be ''P. longissima''. ''"Dolichosoma"'' has been considered to be a ''nomen nudum'' because the holotype was inadequately described through a layer of matrix by Thomas Henry Huxley Thomas Henry Huxley (4 May 1825 – 29 June 1895) was an English biologist and anthropologist specialising in comparative anatomy. He has become known as "Darwin's Bulldog" for his advocacy of Charles Darwin's theory of evolution. The stori ... in 1867. References External linksFossil picture. Aistopods Carboniferous fish of Europe Carboniferous fish of North America Permian fish of Europe Permian fis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pseudophlegethontia Turnbullorum
''Pseudophlegethontia'' is an extinct genus of aïstopod stegocephalians. It is the only member of the family Pseudophlegethontiidae. The only species is the type species ''P. turnbullorum'', named in 2003. Fossils of ''Pseudophlegethontia'' have been found from the Mazon Creek fossil beds in Grundy County, Illinois, a '' conservation lagerstätte'' well known for the exceptional preservation of middle Pennsylvanian taxa. ''Pseudophlegethontia'' has been considered to be morphologically intermediate between derived phlegethontiids and more basal "ophiderpetontids" such as '' Ophiderpeton''. It possesses basal characters such as a relatively short body, "k shaped" ribs, and distinctive skull roof bones while also possessing several more derived features such as a pointed snout, thin gastralia, and a lack of dorsal osteoderms. It is usually, but not unanimously, placed as the sister taxon In phylogenetics, a sister group or sister taxon, also called an adelphotaxon, comprises ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pseudophlegethontia
''Pseudophlegethontia'' is an extinct genus of aïstopod stegocephalians. It is the only member of the family Pseudophlegethontiidae. The only species is the type species ''P. turnbullorum'', named in 2003. Fossils of ''Pseudophlegethontia'' have been found from the Mazon Creek fossil beds in Grundy County, Illinois, a '' conservation lagerstätte'' well known for the exceptional preservation of middle Pennsylvanian taxa. ''Pseudophlegethontia'' has been considered to be morphologically intermediate between derived phlegethontiids and more basal "ophiderpetontids" such as '' Ophiderpeton''. It possesses basal characters such as a relatively short body, "k shaped" ribs, and distinctive skull roof bones while also possessing several more derived features such as a pointed snout, thin gastralia, and a lack of dorsal osteoderms. It is usually, but not unanimously, placed as the sister taxon In phylogenetics, a sister group or sister taxon, also called an adelphotaxon, comprises ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sillerpeton
''Sillerpeton'' is an extinct genus of aïstopod tetrapodomorphs within the family Phlegethontiidae. It contains a single species, ''Sillerpeton permianum'', which is based on braincases and vertebrae from the Early Permian Richards Spur locality of Oklahoma. References See also * List of prehistoric amphibian genera This list of prehistoric amphibians is an attempt to create a comprehensive listing of all genera from the fossil record that have ever been considered to be amphibians, excluding purely vernacular terms. The list includes all commonly accepted gen ... Aistopods Cisuralian amphibians of North America Fossil taxa described in 1978 {{permian-animal-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oestocephalus
''Oestocephalus'' is an extinct genus of aïstopod Stegocephalian that lived during the Carboniferous period. Fossils have been found in the Czech Republic, and in Ohio and Illinois in the United States. It is the type genus of the family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ... Oestocephalidae, although it used to be assigned to the family Ophiderpetontidae, which is now considered paraphyletic.Anderson, J. S. (2003). Cranial anatomy of ''Coloraderpeton brilli'', postcranial anatomy of ''Oestocephalus amphiuminus'', and reconsideration of Ophiderpentontidae (Tetrapoda: Lepospondyli: Aistopoda). ''Journal of Vertebrate Paleontology'' 23(3):532-543. It was named by Edward Drinker Cope in 1868 and now contains two species, ''O. amphiuminus'' and ''O. nanum''. See als ... [...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 lin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oestocephalidae
Oestocephalidae is an extinct family of Late Carboniferous aistopod stegocephalians. Fossils have been found from Ohio, Illinois, and Colorado in the United States; England; and the Czech Republic. It includes the genera '' Coloraderpeton'' and ''Oestocephalus''. Oestocephalids have robust skulls and narrow, rounded snouts. They possess heavily ossified gastralia and dorsal osteoderms. Like other aïstopods, oestocephalids were elongate, having approximately 110 vertebrae. Oestocephalidae was named in 2003, with the type species In zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the species that contains the biological type specime ... being ''Oestocephalus amphiuminus''. References Aistopods Pennsylvanian first appearances Pennsylvanian extinctions {{carboniferous-animal-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coloraderpeton
''Coloraderpeton'' is an extinct genus of aïstopod tetrapodomorphs within the family Oestocephalidae. ''Coloraderpeton'' is known from the Carboniferous Sangre de Cristo Formation of Colorado, and was initially known from vertebrae, ribs, and scales recovered from a UCLA The University of California, Los Angeles (UCLA) is a public land-grant research university in Los Angeles, California. UCLA's academic roots were established in 1881 as a teachers college then known as the southern branch of the California ... field expedition in 1966. Peter Paul Vaughn described these remains in 1969. A skull was later reported in an unpublished 1983 thesis and formally described by Jason S. Anderson in 2003. References Aistopods Carboniferous amphibians Carboniferous amphibians of North America Fossil taxa described in 1969 {{paleo-amphibian-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vertebra
The spinal column, a defining synapomorphy shared by nearly all vertebrates, Hagfish are believed to have secondarily lost their spinal column is a moderately flexible series of vertebrae (singular vertebra), each constituting a characteristic irregular bone whose complex structure is composed primarily of bone, and secondarily of hyaline cartilage. They show variation in the proportion contributed by these two tissue types; such variations correlate on one hand with the cerebral/caudal rank (i.e., location within the backbone), and on the other with phylogenetic differences among the vertebrate taxa. The basic configuration of a vertebra varies, but the bone is its ''body'', with the central part of the body constituting the ''centrum''. The upper (closer to) and lower (further from), respectively, the cranium and its central nervous system surfaces of the vertebra body support attachment to the intervertebral discs. The posterior part of a vertebra forms a vertebral ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
