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Hylaeochampsidae
Hylaeochampsidae is an extinct family (biology), family of basal (phylogenetics), basal eusuchian Crocodylomorpha, crocodylomorphs thought to be closely related to the order Crocodylia. Classification Hylaeochampsidae was first constructed by Charles William Andrews in 1913 to include just one member: ''Hylaeochampsa''. However, a new genus named ''Iharkutosuchus'' was described in 2007 and was found to be a sister taxon of ''Hylaeochampsa'', and thus a member of the family Hylaeochampsidae. The genus ''Heterosuchus'', named in 1887, may also be a member of the family. However, it is likely to be synonym (taxonomy), synonymous with ''Hylaeochampsa'' and has been considered a ''nomen dubium'' by James M. Clark and Mark Norell. Clark and Norell also claimed that there is no evidence to suggest that the two genera form a true clade distinct from other eusuchians, because remains associated with ''Heterosuchus'' are to fragmentary to show any clear phylogenetic relationship. A fourth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Allodaposuchus
''Allodaposuchus'' is an extinct genus of crocodyliforms that lived in what is now southern Europe during the Campanian and Maastrichtian stages of the Late Cretaceous. Although generally classified as a non-crocodylian eusuchian crocodylomorph, it is sometimes placed as one of the earliest true crocodylians. ''Allodaposuchus'' is one of the most common Late Cretaceous crocodylomorphs from Europe, with fossils known from Romania, Spain, and France. Description Like many other Cretaceous crocodylomorphs, ''Allodaposuchus'' has a relatively small body size compared to living crocodylians. The largest known specimen of ''Allodaposuchus'' belongs to an individual that was probably around long. Although the shape varies between species, in general ''Allodaposuchus'' has a short, flattened, and rounded skull. ''Allodaposuchus precedens'' has a brevirostrine or "short-snouted" skull with a snout about the same length as the skull table (the region of the skull behind the eye sockets) a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eusuchia
Eusuchia is a clade of crocodylomorphs that first appeared in the Early Cretaceous with ''Hylaeochampsa''. Along with Dyrosauridae and Sebecosuchia, they were the only crocodyliformes who survived the K-T extinction. Since the other two clades died out 47 and 11 million years ago respectively, all living crocodilian species are eusuchians, as are many extinct forms. Definition Eusuchia was originally defined by Thomas Henry Huxley in 1875 as an apomorphy-based group, meaning that it was defined by shared characteristics rather than relations. These characteristics include pterygoid-bounded choanae and vertebrae which are procoelous (concave from the front and convex from the back). The possibility that these traits may have been convergently evolved in different groups of neosuchians rather than one lineage spurred some modern paleontologists to revise the group's definition to make it defined solely by relations. In 1999, Christopher Brochu redefined Eusuchia as "the last common ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eusuchia
Eusuchia is a clade of crocodylomorphs that first appeared in the Early Cretaceous with ''Hylaeochampsa''. Along with Dyrosauridae and Sebecosuchia, they were the only crocodyliformes who survived the K-T extinction. Since the other two clades died out 47 and 11 million years ago respectively, all living crocodilian species are eusuchians, as are many extinct forms. Definition Eusuchia was originally defined by Thomas Henry Huxley in 1875 as an apomorphy-based group, meaning that it was defined by shared characteristics rather than relations. These characteristics include pterygoid-bounded choanae and vertebrae which are procoelous (concave from the front and convex from the back). The possibility that these traits may have been convergently evolved in different groups of neosuchians rather than one lineage spurred some modern paleontologists to revise the group's definition to make it defined solely by relations. In 1999, Christopher Brochu redefined Eusuchia as "the last common ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iharkutosuchus
''Iharkutosuchus'' (" Iharkút crocodile", after where it was found) is an extinct genus of basal eusuchian crocodyliform. Its fossils have been found in the Santonian-age Upper Cretaceous Csehbánya Formation in the Bakony Mountains of western Hungary. Description It is based on MTM 2006.52.1, a nearly complete skull, and several other partial skulls, isolated skull bones, and numerous teeth are also known. ''Iharkutosuchus'' was a small crocodyliform (skull length , estimated body length ). Its skull was low, and the snout was short. ''Iharkutosuchus'' is unusual in its heterodonty: some of its teeth were complex and multicusped, like mammal teeth. The structure of the skull indicates that it could grind food with a mobile lower jaw, and together with the teeth suggest a diet of fibrous plant material. Classification The genus was described in 2007 by Attila Ősi and colleagues. The type species is ''I. makadii'', named for László Makádi. A 2011 phylogenetic stu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pachycheilosuchus Trinquei
''Pachycheilosuchus'' (meaning "thick lipped crocodile") is an extinct genus of neosuchian from the Early Cretaceous of Texas, United States. Previously known, in part, as the "Glen Rose form", this crocodylomorph is notable for its procoelous vertebrae, otherwise found only in derived eusuchian crocodilians (the vertebrae articulate with a cup on the anterior surface and a rounded posterior surface), a thick margin on the maxillae (the main tooth-bearing bones of the upper jaw; thus "thick lipped crocodile"), and a shield of armor on the neck formed by the fusion of six individual scutes. Description ''Pachycheilosuchus'' is based on SMU 75278, a right maxilla, with the remains of at minimum 13 other individuals also known, representing most of the skeleton except hands, feet, and part of the skull. The remains were recovered near the top of the Glen Rose Formation of Erath County in central Texas, in rocks dating from the early Albian faunal stage. The fossils were found in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hylaeochampsa Vectiana
''Hylaeochampsa'' is an extinct genus of eusuchian crocodylomorphs. It is known only from a partial skull recovered from Barremian-age rocks of the Lower Cretaceous Vectis Formation ( Wealden Group) of the Isle of Wight. This skull, BMNH R 177, is short and wide, with a eusuchian-like palate and inferred enlarged posterior teeth that would have been suitable for crushing.Owen, R. (1874). Monograph on the fossil Reptilia of the Wealden and Purbeck formations. Supplement no. V. Dinosauria (''Iguanodon''). ealden and Purbeck. ''The Palaeontographical Society, London'' 1873:1-18 ''Hylaochampsa'' was described by Richard Owen in 1874, with ''H. vectiana'' as the type species. It may be the same genus as the slightly older '' Heterosuchus'', inferred to have been of similar evolutionary grade, but there is no overlapping material as ''Heterosuchus'' is known only from vertebrae. If the two could be shown to be synonyms, ''Hylaeochampsa'' would have priority because it is the older ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hylaeochampsa
''Hylaeochampsa'' is an extinct genus of eusuchian crocodylomorphs. It is known only from a partial skull recovered from Barremian-age rocks of the Lower Cretaceous Vectis Formation (Wealden Group) of the Isle of Wight. This skull, BMNH R 177, is short and wide, with a eusuchian-like palate and inferred enlarged posterior teeth that would have been suitable for crushing.Owen, R. (1874). Monograph on the fossil Reptilia of the Wealden and Purbeck formations. Supplement no. V. Dinosauria (''Iguanodon''). ealden and Purbeck. ''The Palaeontographical Society, London'' 1873:1-18 ''Hylaochampsa'' was described by Richard Owen in 1874, with ''H. vectiana'' as the type species. It may be the same genus as the slightly older ''Heterosuchus'', inferred to have been of similar evolutionary grade, but there is no overlapping material as ''Heterosuchus'' is known only from vertebrae. If the two could be shown to be synonyms, ''Hylaeochampsa'' would have priority because it is the older name ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pachycheilosuchus
''Pachycheilosuchus'' (meaning "thick lipped crocodile") is an extinct genus of neosuchian from the Early Cretaceous of Texas, United States. Previously known, in part, as the "Glen Rose form", this crocodylomorph is notable for its procoelous vertebrae, otherwise found only in derived eusuchian crocodilians (the vertebrae articulate with a cup on the anterior surface and a rounded posterior surface), a thick margin on the maxillae (the main tooth-bearing bones of the upper jaw; thus "thick lipped crocodile"), and a shield of armor on the neck formed by the fusion of six individual scutes. Description ''Pachycheilosuchus'' is based on SMU 75278, a right maxilla, with the remains of at minimum 13 other individuals also known, representing most of the skeleton except hands, feet, and part of the skull. The remains were recovered near the top of the Glen Rose Formation of Erath County in central Texas, in rocks dating from the early Albian faunal stage. The fossils were found in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pietraroiasuchus
''Pietraroiasuchus'' is an extinct genus of hylaeochampsid eusuchian crocodylomorph from the Pietraroja Plattenkalk of the southern Apennines, Italy. Below is a cladogram showing the phylogenetic In biology, phylogenetics (; from Greek φυλή/ φῦλον [] "tribe, clan, race", and wikt:γενετικός, γενετικός [] "origin, source, birth") is the study of the evolutionary history and relationships among or within groups o ... placement of ''Pietraroiasuchus'' from Buscalioni ''et al.'', 2011: References Early Cretaceous crocodylomorphs of Europe Early Cretaceous reptiles of Europe Prehistoric pseudosuchian genera {{paleo-archosaur-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pietraroiasuchus Ormezzanoi
''Pietraroiasuchus'' is an extinct genus of hylaeochampsid eusuchian crocodylomorph from the Pietraroja Plattenkalk of the southern Apennines, Italy. Below is a cladogram showing the phylogenetic In biology, phylogenetics (; from Greek φυλή/ φῦλον [] "tribe, clan, race", and wikt:γενετικός, γενετικός [] "origin, source, birth") is the study of the evolutionary history and relationships among or within groups o ... placement of ''Pietraroiasuchus'' from Buscalioni ''et al.'', 2011: References Early Cretaceous crocodylomorphs of Europe Early Cretaceous reptiles of Europe Prehistoric pseudosuchian genera {{paleo-archosaur-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cladistic
Cladistics (; ) is an approach to biological classification in which organisms are categorized in groups (" clades") based on hypotheses of most recent common ancestry. The evidence for hypothesized relationships is typically shared derived characteristics ( synapomorphies'')'' that are not present in more distant groups and ancestors. However, from an empirical perspective, common ancestors are inferences based on a cladistic hypothesis of relationships of taxa whose character states can be observed. Theoretically, a last common ancestor and all its descendants constitute a (minimal) clade. Importantly, all descendants stay in their overarching ancestral clade. For example, if the terms ''worms'' or ''fishes'' were used within a ''strict'' cladistic framework, these terms would include humans. Many of these terms are normally used paraphyletically, outside of cladistics, e.g. as a 'grade', which are fruitless to precisely delineate, especially when including extinct species. R ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Node-based Taxon
Phylogenetic nomenclature is a method of nomenclature for taxa in biology that uses phylogenetic definitions for taxon names as explained below. This contrasts with the traditional approach, in which taxon names are defined by a '' type'', which can be a specimen or a taxon of lower rank, and a description in words. Phylogenetic nomenclature is currently regulated by the '' International Code of Phylogenetic Nomenclature'' (''PhyloCode''). Definitions Phylogenetic nomenclature ties names to clades, groups consisting of an ancestor and all its descendants. These groups can equivalently be called monophyletic. There are slightly different ways of specifying the ancestor, which are discussed below. Once the ancestor is specified, the meaning of the name is fixed: the ancestor and all organisms which are its descendants are included in the named taxon. Listing all these organisms (i.e. providing a full circumscription) requires the full phylogenetic tree to be known. In practice, ther ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
