|
Eusuchian
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 co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Confractosuchus
''Confractosuchus'' is a genus of extinct eusuchian crocodyliform from the Cretaceous Winton Formation of Australia. Described as a macro-generalist, ''Confractosuchus'' was found with the bones of a juvenile ornithopod dinosaur in its abdomen. It currently contains a single species, ''Confractosuchus sauroktonos,'' which literally means "broken dinosaur killer." The discovery of ''Confractosuchus'' was announced by the Australian Age of Dinosaurs museum on 11 February 2022, and was published in the journal ''Gondwana Research ''Gondwana Research'' is a peer-reviewed scientific journal with an "all earth science" scope and an emphasis on the origin and evolution of continents. It is part of the Elsevier Elsevier () is a Dutch academic publishing company specializin ...''. It is the second extinct eusuchian crocodyliform genus discovered from the Winton Formation, after '' Isisfordia'' that was discovered during the mid-1990s and named in 2006.'' Discovery and naming ''Conf ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eothoracosaurus
''Eothoracosaurus'' is an extinct monospecific genus of eusuchian Crocodylomorpha, crocodylomorphs found in Eastern United States which existed during the Late Cretaceous period. ''Eothoracosaurus'' is considered to belong to an informally named clade called the "thoracosaurs", named after the closely related ''Thoracosaurus''. Thoracosaurs in general were traditionally thought to be related to the modern false gharial, largely because the nasal bones contact the premaxillae, but phylogenetic work starting in the 1990s instead supported affinities within Gavialoidea, gavialoid exclusive of such forms. Even more recent phylogenetic studies suggest that thoracosaurs might instead be non-crocodilian eusuchians. Discovery and naming Fossils are known from the Ripley Formation in Mississippi and date back to the early Maastrichtian stage of the Late Cretaceous. Some fragmentary material from the Coon Creek Formation of western Tennessee dating back to the late Campanian (slightly olde ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Borealosuchus
''Borealosuchus'' (meaning "boreal crocodile") is an extinct genus of crocodyliforms that lived from the Late Cretaceous to the Eocene in North America. It was named by Chris Brochu in 1997 for several species that had been assigned to ''Leidyosuchus''. The species assigned to it are: ''B. sternbergii'', the type species, from the Maastrichtian (Late Cretaceous) of Colorado, Montana, North Dakota, South Dakota, and Wyoming; ''B. acutidentatus'', from the Paleocene of Saskatchewan; ''B. formidabilis'', from the Paleocene of North Dakota; ''B. griffithi'', from the Paleocene of Alberta; and ''B. wilsoni'', from the Eocene of Wyoming. ''B. formidabilis'' is particularly well-known, represented by the remains of many individuals from the Wannagan Creek site in North Dakota. ''Borealosuchus'' was a mid-sized crocodyliform; ''B. acutidentatus'' reached up to in length with a skull. Taxonomy Six species of ''Borealosuchus'' are currently recognized. In order of their naming, they ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crocodylomorpha
Crocodylomorpha is a group of pseudosuchian archosaurs that includes the crocodilians and their extinct relatives. They were the only members of Pseudosuchia to survive the end-Triassic extinction. During Mesozoic and early Cenozoic times, crocodylomorphs were far more diverse than they are now. Triassic forms were small, lightly built, active terrestrial animals. The earliest and most primitive crocodylomorphs are represented by " sphenosuchians", a paraphyletic assemblage containing small-bodied forms with elongated limbs that walked upright, which represents the ancestral morphology of Crocodylomorpha. These forms persisted until the end of the Jurassic. During the Jurassic, Crocodylomorphs morphologically diversified into numerous niches, including into the aquatic and marine realms. Evolutionary history When their extinct species and stem group are examined, the crocodylian lineage (clade Pseudosuchia, formerly Crurotarsi) proves to have been a very diverse and adaptive ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aegyptosuchidae
Aegyptosuchidae is an extinct family of eusuchian crocodyliforms from the Cretaceous period of Africa. They are characterized by their large size and flat heads. The family includes two genera, '' Aegyptosuchus'' and '' Aegisuchus''. Aegyptosuchidae was originally established as the monotypic family name for '' Aegyptosuchus peyeri'' in 1933. Upon the discovery of the fellow aegyptosuchid '' Aegisuchus witmeri'' in 2012 by Holliday and Gardner, Aegyptosuchidae was phylogenetically defined as the least inclusive clade containing ''Aegisuchus witmeri'' and ''Aegyptosuchus peyeri'', so long as it does not include ''Alligator mississippiensis'' (American alligator), ''Bernissartia fagesii'', ''Crocodylus niloticus'' (Nile crocodile), ''Gavialis gangeticus'' (gharial), ''Hylaeochampsa vectiana'', or '' Susisuchus anatoceps''. Aegyptosuchidae belongs to the clade Eusuchia, and is proposed to be the sister clade to the crown group Crocodylia, which contains all extant (living) crocodili ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clade
A clade (), also known as a monophyletic group or natural group, is a group of organisms that are monophyletic – that is, composed of a common ancestor and all its lineal descendants – on a phylogenetic tree. Rather than the English term, the equivalent Latin term ''cladus'' (plural ''cladi'') is often used in taxonomical literature. The common ancestor may be an individual, a population, or a species (extinct or 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 taxa that are not clades; that is, taxa that are not monophyletic. Some of the relationships between organisms ... [...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] |
Blackwell Publishing
Wiley-Blackwell is an international scientific, technical, medical, and scholarly publishing business of John Wiley & Sons. It was formed by the merger of John Wiley & Sons Global Scientific, Technical, and Medical business with Blackwell Publishing in 2007.About Wiley-Blackwell John Wiley & Sons, Inc. Wiley-Blackwell is now an imprint that publishes a diverse range of academic and professional fields, including , , , |
Sebecosuchia
Sebecosuchia is an extinct group of mesoeucrocodylian crocodyliforms that includes the families Sebecidae and Baurusuchidae. The group was long thought to have first appeared in the Late Cretaceous with the baurusuchids and become extinct in the Miocene with the last sebecids, but ''Razanandrongobe'' pushes the origin of Sebecosuchia to the Middle Jurassic. Fossils have been found primarily from South America but have also been found in Europe, North Africa, Madagascar, and the Indian subcontinent. History and phylogeny Sebecosuchia was first constructed in 1937 by George Gaylord Simpson.Simpson, G.G. 1937. "New reptiles from the Eocene of South America". ''American Museum Novitates'' 967: 1-20 In 1946 the concept was again used by American paleontologist Edwin Colbert to include ''Sebecus'' and Baurusuchidae. ''Sebecus'', which had been known from South America since 1937, was an unusual crocodyliform with a deep snout and teeth that were ziphodont, or serrated and laterally comp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dyrosauridae
Dyrosauridae is a family of extinct neosuchian crocodyliforms that lived from the Late Cretaceous (Maastrichtian) to the Eocene. Dyrosaurid fossils are globally distributed, having been found in Africa, Asia, Europe, North America and South America. Over a dozen species are currently known, varying greatly in overall size and cranial shape. A majority were aquatic, some terrestrial and others fully marine (see locomotion below), with species inhabiting both freshwater and marine environments. Ocean-dwelling dyrosaurids were among the few marine reptiles to survive the Cretaceous–Paleogene extinction event. The dyrosaurids were a group of mostly marine, long jawed, crocodile-like quadrupeds up to long. The largest dyrosaurid was probably ''Phosphatosaurus'' estimated at in length. Based on bone tissue evidence, it has been hypothesized that they were slow-growing near-shore marine animals with interlocking closed jaws, able to swim as well as walk on land. External nostrils at ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Planocraniidae
Planocraniidae is an extinct family (biology), family of eusuchian crocodyliforms known from the Paleogene of Asia, Europe and North America. The family was coined by Li in 1976, and contains three genera, ''Boverisuchus'', ''Duerosuchus'' and ''Planocrania''. Planocraniids were highly specialized crocodyliforms that were adapted to living on land. They had extensive body armor, long legs, and blunt claws resembling hooves, and are sometimes informally called "hoofed crocodiles". Classification Prior to 2013, the term Pristichampsidae/Pristichampsinae was used for this group. However, the type specimen of ''Pristichampsus'' was found to be undiagnostic, and considered to be a ''nomen dubium''. As such, Brochu (2013) transferred the other species placed in ''Pristichampsus'' to ''Boverisuchus'', and resurrected Planocraniidae to replace Pristichampsidae/Pristichampsinae as the name for the clade. Brochu cladistically defined Planocraniidae as ''Planocrania hengdongensis'' and croco ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crocodyliformes
Crocodyliformes is a clade of crurotarsan archosaurs, the group often traditionally referred to as "crocodilians". They are the first members of Crocodylomorpha to possess many of the features that define later relatives. They are the only pseudosuchians to survive the K-Pg extinction event. In 1988, Michael J. Benton and James M. Clark argued that all traditional names for well-known groups of animals should be restricted to their crown clades, that is, used only for natural groups comprising all living members of any given lineage. This posed a problem for the crocodilians, because the name Crocodylia, while used in various ways by various scientists, had always included not only living crocodilians but many of their extinct ancestors known only from the fossil record.Benton, M.J. and Clark, J.M. (1988). "Archosaur phylogeny and the relationships of the Crocodylia." Pp. 295–338 in Benton, M.J. (ed.), ''The phylogeny and classification of the Tetrapods, volume 1''. Oxford: Cl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
.jpg "Click for more on -> Borealosuchus")
