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Arizonerpeton
''Arizonerpeton'' is an extinct genus of nectridean lepospondyl. It contains a single species, ''Arizonerpeton wellsi''. It lived in what is now the Swisshelm Mountains of modern-day Arizona, United States. This locality belongs to the Black Prince Limestone Formation, which is dated to the middle Pennsylvanian sub-period of the Carboniferous period. Description ''Arizonerpeton'' is known exclusively from a collection of unusual vertebrae collected by Robert Wells, the namesake of its specific name. These vertebrae can be designated as belonging to the order Nectridea, a collection of long-tailed tetrapods ( amphibians in the broad sense) also including the famous "boomerang-headed" ''Diplocaulus''. Like other nectrideans, ''Arizonerpeton's'' vertebrae had a single main body (a pleurocentrum) fused to a plate-like neural spine jutting out of the top. The flared rims of the front and rear surfaces of the pleurocentum possesses small structures which would have formed tongue-an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Prehistoric Amphibians
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 genera, but also genera that are now considered invalid, doubtful ('' nomina dubia''), or were not formally published (''nomina nuda''), as well as junior synonyms of more established names, and genera that are no longer considered amphibians. Modern forms are excluded from this list. The list currently includes 454 names. Naming conventions and terminology Naming conventions and terminology follow the International Code of Zoological Nomenclature. Technical terms used include: * Junior synonym: A name which describes the same taxon as a previously published name. If two or more genera are formally designated and the type specimens are later assigned to the same genus, the first to be published (in chronological order) is the senior synon ... [...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] |
Prehistoric Amphibian
This list of prehistoric amphibians is an attempt to create a comprehensive listing of all Genus, genera from the fossil record that have ever been considered to be amphibians, excluding purely vernacular terms. The list includes all commonly accepted genera, but also genera that are now considered invalid, doubtful (''nomen dubium, nomina dubia''), or were not formally published (''nomen nudum, nomina nuda''), as well as synonym (zoology), junior synonyms of more established names, and genera that are no longer considered amphibians. Modern forms are excluded from this list. The list currently includes 454 names. Naming conventions and terminology Naming conventions and terminology follow the International Code of Zoological Nomenclature. Technical terms used include: * Synonym (zoology), Junior synonym: A name which describes the same taxon as a previously published name. If two or more genera are formally designated and the type (zoology), type specimens are later assigned to th ... [...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] |
Tongue And Groove
Tongue and groove is a method of fitting similar objects together, edge to edge, used mainly with wood, in flooring, parquetry, panelling, and similar constructions. Tongue and groove joints allow two flat pieces to be joined strongly together to make a single flat surface. Before plywood became common, tongue and groove boards were also used for sheathing buildings and to construct concrete formwork. A strong joint, the tongue and groove joint is widely used for re-entrant angles. The effect of wood shrinkage is concealed when the joint is beaded or otherwise moulded.Tongue and GrooveWoodworkDetails.com/ref> In expensive cabinet work, glued dovetail and multiple tongue and groove are used. Each piece has a slot (the ''groove'' or '' dado'') cut all along one edge, and a thin, deep ridge (the ''tongue'') on the opposite edge. The tongue projects a little less than the depth of the groove. Two or more pieces thus fit together closely. The joint is not normally glued, as shrink ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Incertae Sedis
' () or ''problematica'' is a term used for a taxonomic group where its broader relationships are unknown or undefined. Alternatively, such groups are frequently referred to as "enigmatic taxa". In the system of open nomenclature, uncertainty at specific taxonomic levels is indicated by ' (of uncertain family), ' (of uncertain suborder), ' (of uncertain order) and similar terms. Examples *The fossil plant '' Paradinandra suecica'' could not be assigned to any family, but was placed ''incertae sedis'' within the order Ericales when described in 2001. * The fossil ''Gluteus minimus'', described in 1975, could not be assigned to any known animal phylum. The genus is therefore ''incertae sedis'' within the kingdom Animalia. * While it was unclear to which order the New World vultures (family Cathartidae) should be assigned, they were placed in Aves ''incertae sedis''. It was later agreed to place them in a separate order, Cathartiformes. * Bocage's longbill, ''Motacilla bocagii' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ctenerpeton
''Ctenerpeton'' is an extinct genus of nectridean lepospondyl within the family Urocordylidae. See also * Prehistoric amphibian * List of prehistoric amphibians 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 g ... References Holospondyls {{Lepospondyli-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Urocordylidae
The Urocordylidae are an extinct family (biology), family of nectridean lepospondyl amphibians. Urocordylids lived during the Late Carboniferous and Early Permian in what is now Europe and North America and are characterized by their very long, paddle-like tails. In life, they were probably newt-like and aquatic. Fossils have been found from Ireland, France, and the eastern United States. The family was named by English naturalist Richard Lydekker in 1889 and includes the well-known genera ''Urocordylus'' and ''Sauropleura'', as well as several others based on less-complete material. The family Urocordylidae is divided into two subfamilies, the Urocordylinae and the Sauropleurinae. The two groups are distinguished by the shapes of their skulls; urocordylines have short, blunt skulls, and sauropleurines have longer, pointed skulls. Description Urocordylids are distinguished by their elongated tails. Each tail vertebra has an upper crest of bone called a neural arch and a lower cr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diceratosaurus
''Diceratosaurus'' is an extinct genus of nectridean lepospondyl within the family Keraterpetontidae. Fossils of ''Diceratosaurus'' were first described by Edward Drinker Cope in 1874. The species ''D. brevirostris'' is well known from Jefferson County, Ohio, with approximately 50 specimens having been collected from the Ohio Diamond Coal Mine. The mine was situated in the village of Linton, which became obscure soon after operations were completed and the mine closed in 1921. See also * Prehistoric amphibian * List of prehistoric amphibians 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 g ... References Carboniferous amphibians of North America Diplocaulids Carboniferous amphibians Fossil taxa described in 1903 {{Lepospondyli-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diplocaulidae
The Diplocaulidae ("double cauls") is an extinct family of lepospondyl amphibians that arose during the Late Carboniferous and died out in the Late Permian. They are distinguished from other amphibians, extinct and extant, by the presence of strange, horn-like protrusions jutting out from the rear of their skulls; in some genera said protrusions gave their heads an almost boomerang-like outline. Phylogeny Below is a cladogram A cladogram (from Greek ''clados'' "branch" and ''gramma'' "character") is a diagram used in cladistics to show relations among organisms. A cladogram is not, however, an evolutionary tree because it does not show how ancestors are related to d ... modified from Germain (2010): References Diplocaulids Pennsylvanian first appearances Lopingian extinctions {{Lepospondyli-stub es:Keraterpetontidae ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Articular Processes
The articular processes or zygapophyses (Greek ζυγον = "yoke" (because it links two vertebrae) + απο = "away" + φυσις = "process") of a vertebra are projections of the vertebra that serve the purpose of fitting with an adjacent vertebra. The actual region of contact is called the ''articular facet''.Moore, Keith L. et al. (2010) ''Clinically Oriented Anatomy'', 6th Ed, p.442 fig. 4.2 Articular processes spring from the junctions of the pedicles and laminæ, and there are two right and left, and two superior and inferior. These stick out of an end of a vertebra to lock with a zygapophysis on the next vertebra, to make the backbone more stable. * The superior processes or prezygapophysis project upward from a lower vertebra, and their articular surfaces are directed more or less backward (oblique coronal plane). * The inferior processes or postzygapophysis project downward from a higher vertebra, and their articular surfaces are directed more or less forward and outwa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amphibian
Amphibians are tetrapod, four-limbed and ectothermic vertebrates of the Class (biology), class Amphibia. All living amphibians belong to the group Lissamphibia. They inhabit a wide variety of habitats, with most species living within terrestrial animal, terrestrial, fossorial, arboreal or freshwater aquatic ecosystems. Thus amphibians typically start out as larvae living in water, but some species have developed behavioural adaptations to bypass this. The young generally undergo metamorphosis from larva with gills to an adult air-breathing form with lungs. Amphibians use their skin as a secondary respiratory surface and some small terrestrial salamanders and frogs lack lungs and rely entirely on their skin. They are superficially similar to reptiles like lizards but, along with mammals and birds, reptiles are amniotes and do not require water bodies in which to breed. With their complex reproductive needs and permeable skins, amphibians are often ecological indicators; in re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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