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Reptiliomorphs
Reptiliomorpha (meaning reptile-shaped; in PhyloCode known as ''Pan-Amniota'') is a clade containing the amniotes and those tetrapods that share a more recent common ancestor with amniotes than with living amphibians (lissamphibians). It was defined by Michel Laurin (2001) and Vallin and Laurin (2004) as the largest clade that includes ''Homo sapiens'', but not '' Ascaphus truei'' (tailed frog). Laurin and Reisz (2020) defined Pan-Amniota as the largest total clade containing ''Homo sapiens'', but not '' Pipa pipa'', '' Caecilia tentaculata'', and '' Siren lacertina''. The informal variant of the name, "reptiliomorphs", is also occasionally used to refer to stem-amniotes, i.e. a grade of reptile-like tetrapods that are more closely related to amniotes than they are to lissamphibians, but are not amniotes themselves; the name is used in this meaning e.g. by Ruta, Coates and Quicke (2003). An alternative name, "Anthracosauria", is also commonly used for the group, but is confusing ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetrapod
A tetrapod (; from Ancient Greek :wiktionary:τετρα-#Ancient Greek, τετρα- ''(tetra-)'' 'four' and :wiktionary:πούς#Ancient Greek, πούς ''(poús)'' 'foot') is any four-Limb (anatomy), limbed vertebrate animal of the clade Tetrapoda (). Tetrapods include all Neontology#Extant taxa versus extinct taxa, extant and Extinction, extinct amphibians and amniotes, with the latter in turn Evolution, evolving into two major clades, the Sauropsida, sauropsids (reptiles, including dinosaurs and therefore birds) and synapsids (extinct pelycosaur, "pelycosaurs", therapsids and all extant mammals, including Homo sapiens, humans). Hox gene mutations have resulted in some tetrapods becoming Limbless vertebrate, limbless (snakes, legless lizards, and caecilians) or two-limbed (cetaceans, sirenians, Bipedidae, some lizards, kiwi (bird), kiwis, and the extinct moa and elephant birds). Nevertheless, they still qualify as tetrapods through their ancestry, and some retain a pair of ves ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Embolomeri
Embolomeri is an Order (biology), order of Tetrapod, tetrapods or Stem-group, stem-tetrapods, possibly members of Reptiliomorpha. Embolomeres first evolution, evolved in the Early Carboniferous (Mississippian age, Mississippian) Period and were the largest and most successful predatory tetrapods of the Late Carboniferous (Pennsylvanian (geology), Pennsylvanian) Period. They were specialized semiaquatic predators with long bodies for eel-like undulatory swimming. Embolomeres are characterized by their Vertebra, vertebral centra, which are formed by two cylindrical segments, the pleurocentrum at the rear and intercentrum at the front. These segments are equal in size. Most other tetrapods have pleurocentra and intercentra which are drastically different in size and shape. Embolomeres were among the earliest large carnivorous tetrapods, with members such as the crocodilian-like ''Proterogyrinus'' appearing in the Viséan, Visean stage of the Carboniferous. They declined in diversity d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mississippian (geology)
The Mississippian ( ), also known as Lower Carboniferous or Early Carboniferous, is a subperiod in the geologic timescale or a subsystem of the geologic record. It is the earlier of two subperiods of the Carboniferous period lasting from roughly 358.9 to 323.2 million years ago. As with most other geochronologic units, the rock beds that define the Mississippian are well identified, but the exact start and end dates are uncertain by a few million years. The Mississippian is so named because rocks with this age are exposed in the Mississippi Valley. The Mississippian was a period of marine transgression in the Northern Hemisphere: the sea level was so high that only the Fennoscandian Shield and the Laurentian Shield were dry land. The cratons were surrounded by extensive delta systems and lagoons, and carbonate sedimentation on the surrounding continental platforms, covered by shallow seas. In North America, where the interval consists primarily of marine limestones, i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Casineria
''Casineria'' is an extinct genus of tetrapodomorph which lived about 340–334 million years ago in the Mississippian (geologic period), Mississippian epoch of the Carboniferous period. Its Generic name (biology), generic name, ''Casineria'', is a latinization of Cheese Bay, the site near Edinburgh, Scotland, where the holotype fossil was found. When originally described in 1999, it was identified as a transitional fossil noted for its mix of basal (amphibian-like) and advanced (reptile-like) characteristics, putting it at or very near the origin of the amniotes, the group containing all Mammal, mammals, Bird, birds, modern reptiles, and other descendants of their reptile-like Most recent common ancestor, common ancestor. However, the sole known fossil is lacking key elements such as a skull, making exact analysis difficult. As a result, the classification of ''Casineria'' has been more controversial in analyses conducted since 1999. Other proposed affinities include a placement ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amniotes
Amniotes are tetrapod vertebrate animals belonging to the clade Amniota, a large group that comprises the vast majority of living terrestrial and semiaquatic vertebrates. Amniotes evolved from amphibious stem tetrapod ancestors during the Carboniferous period. Amniota is defined as the smallest crown clade containing humans, the Greek tortoise, and the Nile crocodile. Amniotes are distinguished from the other living tetrapod clade — the non-amniote lissamphibians (frogs/ toads, salamanders/ newts and caecilians) — by: the development of three extraembryonic membranes ( amnion for embryonic protection, chorion for gas exchange, and allantois for metabolic waste disposal or storage); thicker and keratinized skin; costal respiration (breathing by expanding/constricting the rib cage); the presence of adrenocortical and chromaffin tissues as a discrete pair of glands near their kidneys; more complex kidneys; the presence of an astragalus for better ext ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clade
In biology, a clade (), also known as a Monophyly, monophyletic group or natural group, is a group of organisms that is composed of a common ancestor and all of its descendants. Clades are the fundamental unit of cladistics, a modern approach to taxonomy adopted by most biological fields. The common ancestor may be an individual, a population, or a species (extinct or Extant taxon, extant). Clades are nested, one in another, as each branch in turn splits into smaller branches. These splits reflect evolutionary history as populations diverged and evolved independently. Clades are termed ''monophyletic'' (Greek: "one clan") groups. Over the last few decades, the cladistic approach has revolutionized biological classification and revealed surprising evolutionary relationships among organisms. Increasingly, taxonomists try to avoid naming Taxon, taxa that are not clades; that is, taxa that are not Monophyly, monophyletic. Some of the relationships between organisms that the molecul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PhyloCode
The ''International Code of Phylogenetic Nomenclature'', known as the ''PhyloCode'' for short, is a formal set of rules governing phylogenetic nomenclature. Its current version is specifically designed to regulate the naming of clades, leaving the governance of species names up to the rank-based nomenclature codes ('' ICN'', '' ICNCP'', '' ICNP'', '' ICZN'', '' ICVCN''). The ''PhyloCode'' is associated with the International Society for Phylogenetic Nomenclature (ISPN). The companion volume, ''Phylonyms'', establishes 300 taxon names under ''PhyloCode'', serving as examples for those unfamiliar with the code. RegNum is an associated online database for registered clade names. The ''PhyloCode'' regulates phylogenetic nomenclature by providing rules for deciding which associations of names and definitions are considered established, which of those will be considered homonyms or synonyms, and which one of a set of synonyms or homonyms will be considered accepted (generally the one ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amniota
Amniotes are tetrapod vertebrate animals belonging to the clade Amniota, a large group that comprises the vast majority of living terrestrial and semiaquatic vertebrates. Amniotes evolved from amphibious stem tetrapod ancestors during the Carboniferous period. Amniota is defined as the smallest crown clade containing humans, the Greek tortoise, and the Nile crocodile. Amniotes are distinguished from the other living tetrapod clade — the non-amniote lissamphibians (frogs/ toads, salamanders/newts and caecilians) — by: the development of three extraembryonic membranes ( amnion for embryonic protection, chorion for gas exchange, and allantois for metabolic waste disposal or storage); thicker and keratinized skin; costal respiration (breathing by expanding/constricting the rib cage); the presence of adrenocortical and chromaffin tissues as a discrete pair of glands near their kidneys; more complex kidneys; the presence of an astragalus for better extremity ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diadectomorpha
Diadectomorpha is a clade of large tetrapods that lived in Euramerica during the Carboniferous and Early Permian periods and in Asia during Late Permian (Wuchiapingian), They have typically been classified as advanced reptiliomorphs (transitional between "amphibians" ''sensu lato'' and amniotes) positioned close to, but outside of the clade Amniota, though some recent research has recovered them as the sister group to the traditional Synapsida within Amniota, based on inner ear anatomy and cladistic analyses. They include both large (up to 2 meters long) carnivorous and even larger (to 3 meters) herbivorous forms, some semi-aquatic and others fully terrestrial. The diadectomorphs seem to have originated during late Mississippian times, although they only became common after the Carboniferous rainforest collapse and flourished during the Late Pennsylvanian and Early Permian periods. Anatomy Diadectomorphs possessed both amphibian-like and amniote-like characteristics. Origin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protorothyridae
Protorothyrididae is an extinct family of small, lizard-like reptiles belonging to Eureptilia. Their skulls did not have fenestrae, like the more derived diapsids. Protorothyridids lived from the Late Carboniferous to Early Permian periods, in what is now North America. Many genera of primitive reptiles were thought to be protorothyridids. ''Brouffia'', ''Coelostegus'', ''Paleothyris'' and ''Hylonomus'', for example, were found to be more basal eureptiles in Muller and Reisz (2006), making the family as historically defined paraphyletic, though three genera, ''Protorothyris, Anthracodromeus,'' and ''Cephalerpeton'', were recovered as a monophyletic group. ''Anthracodromeus'', ''Paleothyris'', and ''Protorothyris'' were recovered as a monophyletic group in Ford and Benson (2020) (who did not sample ''Cephalerpeton''), who recovered them as more derived than captorhinids and ''Hylonomus'', but less so than araeoscelidians. ''Anthracodromeus'' is the earliest known reptile to displ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Captorhinidae
Captorhinidae is an extinct family of tetrapods, traditionally considered primitive Reptile, reptiles, known from the late Carboniferous to the Late Permian. They had a cosmopolitan distribution across Pangea. Description Captorhinids are a clade of small to very large lizard-like animals that date from the Late Carboniferous through the Permian. Their skulls were much stronger than those of their relatives, the protorothyridids, and had teeth that were better able to deal with tough plant material. The postcranial skeleton is similar to those of seymouriamorphs and diadectomorphs; these animals were grouped together with the captorhinids in the order Cotylosauria as the first reptiles in the early 20th century, but are now usually regarded as Stem group, stem-amniotes no closer to reptiles than to mammals. Captorhinids have broad, robust skulls that are generally triangular in shape when seen in dorsal view. The premaxillae are characteristically downturned. The largest captorh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solenodonsaurus
''Solenodonsaurus'' ("single-tooth lizard") is an extinct genus of reptiliomorphs that lived in what is now Czech Republic, during the Westphalian stage. Description ''Solenondosaurus'' had snout-vent length with a skull length . ''Solenodonsaurus'' shows a curious mix of characters making it difficult to place phylogenetically. The teeth lack labyrinthodont folding of the enamel, and it skull has a much smaller otic notch than seen in other reptiliomorph amphibians. Yet general build ties it in with the Diadectomorpha. Laurin, M. and Rize R.R. (1999): A new study of ''Solenodonsaurus janenschi'', and a reconsideration of amniote origins and stegocephalian evolution. ''Canadian Journal of Earth Science'', no 36 (8): pp 1239–1255 (1999)/ref> Paleobiology ''Solenodonsaurus'' was likely best adapted to life on land, as opposed to living in an aquatic environment like many other early tetrapods. The limbs and pelvis are incomplete in all known specimens of ''Solenodonsaurus'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
