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Aïstopod
Aistopoda (Greek for " avingnot-visible feet") is an order of highly specialised snake-like stegocephalians known from the Carboniferous and 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 period and continue through to the Early Permian. The skull is small but very specialised, with large orbits, and large 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 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 230 vertebrae. The vertebrae were holospondylous, having only a single ossification per segment. They l ... [...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 tetrapodomorphs 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'', as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phlegethontia
''Phlegethontia'' is an extinct genus of aïstopod tetrapodomorphs 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 who specialized in comparative anatomy. He has become known as "Darwin's Bulldog" for his advocacy of Charles Darwin's theory of evolution. The stor ... in 1867. References External linksFossil picture. Aistopoda Pennsylvanian sarcopterygians Carboniferous sarcopterygians of Europe Carboniferous sarcopterygians ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pseudophlegethontia Turnbullorum
''Pseudophlegethontia'' is an extinct genus of aïstopod tetrapodomorphs. 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 ... Aistopoda Cisuralian sarcopterygians of North America Fossil taxa described in 1978 {{paleo-tetrapodomorph-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oestocephalus
''Oestocephalus'' is an extinct genus of Aïstopoda, aïstopod tetrapodomorphs 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 (biology), family 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 also References Aistopoda Pennsylvanian sarcopterygians of North America Pennsylvanian sarcopterygians of Europe Taxa named by Edward Drinker Cope Fossil taxa described in 1868 {{paleo-tetrapodomorph-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carboniferous
The Carboniferous ( ) is a Geologic time scale, geologic period and System (stratigraphy), system of the Paleozoic era (geology), era that spans 60 million years, from the end of the Devonian Period Ma (million years ago) to the beginning of the Permian Period, Ma. It is the fifth and penultimate period of the Paleozoic era and the fifth period of the Phanerozoic eon (geology), eon. In North America, the Carboniferous is often treated as two separate geological periods, the earlier Mississippian (geology), Mississippian and the later Pennsylvanian (geology), Pennsylvanian. The name ''Carboniferous'' means "coal-bearing", from the Latin ("coal") and ("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. Carboniferous is the per ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oestocephalidae
Oestocephalidae is an extinct family of Late Carboniferous aistopod tetrapodomorphs. 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 International_Code_of_Zoological_Nomenclature, 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 spe ... being ''Oestocephalus amphiuminus''. References Aistopoda Pennsylvanian first appearances Pennsylvanian extinctions Tetrapodomorph families {{paleo-tetrapodomorph-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coloraderpeton
''Coloraderpeton'' is an extinct tetrapodomorph in the genus aïstopod 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, United States. Its academic roots were established in 1881 as a normal school then known as the southern branch of the C ... 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 Aistopoda Pennsylvanian sarcopterygians of North America Fossil taxa described in 1969 {{paleo-tetrapodomorph-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vertebra
Each vertebra (: vertebrae) is an irregular bone with a complex structure composed of bone and some hyaline cartilage, that make up the vertebral column or spine, of vertebrates. The proportions of the vertebrae differ according to their spinal segment and the particular species. The basic configuration of a vertebra varies; the vertebral body (also ''centrum'') is of bone and bears the load of the vertebral column. The upper and lower surfaces of the vertebra body give attachment to the intervertebral discs. The posterior part of a vertebra forms a vertebral arch, in eleven parts, consisting of two pedicles (pedicle of vertebral arch), two laminae, and seven processes. The laminae give attachment to the ligamenta flava (ligaments of the spine). There are vertebral notches formed from the shape of the pedicles, which form the intervertebral foramina when the vertebrae articulate. These foramina are the entry and exit conduits for the spinal nerves. The body of the vertebr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
