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Aistopod
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 la ... [...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'', a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nectridea
Nectridea is the name of an extinct order of lepospondyl tetrapods from the Carboniferous and Permian periods, including animals such as ''Diplocaulus''. In appearance, they would have resembled modern newts or aquatic salamanders, although they are not close relatives of modern amphibians. They were characterized by long, flattened tails to aid in swimming, as well as numerous features of the vertebrae. Description Nectrideans are a diverse group of tetrapods, including the aquatic Urocordylidae, the presumably terrestrial Scincosauridae, and the bizarre horned members of Diplocaulidae (also known as Keraterpetonidae), which includes the "boomerang-headed" ''Diplocaulus'', one of the most famous genera of prehistoric amphibians (in the traditional sense of the word). By the time the earliest known nectrideans appeared in the Late Carboniferous fossil record, they had already diversified into these families, indicating that basal nectrideans are unknown. These different famili ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ophiderpeton
''Ophiderpeton'' (from el, ὄφῐς , 'snake' and el, ἑρπετόν 'creeper') is an extinct genus of aistopod tetrapodomorphs from the early Carboniferous to the early Permian. Remains of this genus are widespread and were found in Ohio, United States, Ireland, and the Czech Republic (Central Europe). Like other aistopods, ''Ophiderpeton'' was snake-like, without any trace of limbs. Its body was about long, with 230 vertebrae. The skull measured , and large, forward-facing eyes, suggesting a hunting lifestyle. It probably lived in burrows, feeding on insects, worms, millipedes, and snails. Many species are classified in the genus, and similar animals, ''Phlegethontia'' and '' Sillerpeton'', are known. An earlier genus, '' Lethiscus'', is known from the Carboniferous and Early Permian The Permian ( ) is a geologic period and System (stratigraphy), stratigraphic system which spans 47 million years from the end of the Carboniferous Period million years ago (Mya), to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phlegethontioidea
Phlegethontioidea is a clade of aistopod amphibians including the families Phlegethontiidae and Pseudophlegethontiidae. It is a stem-based taxon defined in phylogenetic terms as all aistopods sharing a more recent common ancestor with ''Phlegethontia'' than ''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 ...''. References Carboniferous amphibians Permian amphibians Aistopods {{paleo-amphibian-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phlegethontiidae
Phlegethontiidae is a family of extinct aistopod amphibians including the genera ''Phlegethontia'' and ''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 local ...''. Carboniferous amphibians Permian amphibians Aistopods {{paleo-amphibian-stub ... [...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] |
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] |
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] |
Ecological Niche
In ecology, a niche is the match of a species to a specific environmental condition. Three variants of ecological niche are described by It describes how an organism or population responds to the distribution of resources and competitors (for example, by growing when resources are abundant, and when predators, parasites and pathogens are scarce) and how it in turn alters those same factors (for example, limiting access to resources by other organisms, acting as a food source for predators and a consumer of prey). "The type and number of variables comprising the dimensions of an environmental niche vary from one species to another ndthe relative importance of particular environmental variables for a species may vary according to the geographic and biotic contexts". See also Chapter 2: Concepts of niches, pp. 7 ''ff'' A Grinnellian niche is determined by the habitat in which a species lives and its accompanying behavioral adaptations. An Eltonian niche emphasizes that a spec ... [...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] |
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 arch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
