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Metasuchia
Metasuchia is a major clade within the superorder Crocodylomorpha. It is split into two main groups, Notosuchia and Neosuchia. Notosuchia is an extinct group that contains primarily small-bodied Cretaceous taxa with heterodont dentition. Neosuchia includes the extant crocodylians and basal taxa, such as peirosaurids and pholidosaurids. It is phylogenetically defined by Sereno ''et al.'' (2001) as a clade containing ''Notosuchus terrestris'', ''Crocodylus niloticus'', and all descendants of their common ancestor. Phylogenetics The phylogeny of basal metasuchians has experienced many revisions in recent years. The phylogeny of notosuchians has been particularly revised, with the construction of Sebecia by Larsson and Sues (2007) to include peirosaurids in the clade. Previously, peirosaurids were placed outside Notosuchia. Larsson and Sues (2007) also suggested that Sebecosuchia (containing the families Baurusuchidae and Sebecidae) was polyphyletic, as ''Baurusuchus'' was p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sebecus
''Sebecus'' (meaning " Sebek" in Latin) is an extinct genus of sebecid crocodylomorph from Eocene of South America. Like other sebecosuchians, it was entirely terrestrial and carnivorous. The genus is currently represented by two species, the type ''S. icaeorhinus'' and ''S. ayrampu''. Several other species have been referred to ''Sebecus'', but were later reclassified as their own genera. History and species Named by American paleontologist George Gaylord Simpson in 1937, ''Sebecus'' was one of the first known sebecosuchians. Simpson described the type species, ''S. icaeorhinus'', from a fragmented skull and lower jaw found in the Sarmiento Formation. The specimen was discovered by the American Museum of Natural History's First Scarritt Expedition to Patagonia, during 1930 and 1931. Teeth had been known since 1906 when Argentine paleontologist Florentino Ameghino associated them with carnivorous dinosaurs. The more complete material found by Simpson firmly established that the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Itasuchus
''Itasuchus'' is an extinct genus of crocodylomorph from the Late Cretaceous of Brazil. Fossils of the type species ''I. jesuinoi'', first described in 1955 by Llewellyn Ivor Price, have been found from the Serra da Galga Formation (Maastrichtian age) in Uberaba, Brazil. It is known from a 370 mm skull The skull is a bone protective cavity for the brain. The skull is composed of four types of bone i.e., cranial bones, facial bones, ear ossicles and hyoid bone. However two parts are more prominent: the cranium and the mandible. In humans, th ..., suggesting a total length of about 3 m (10 ft). References Terrestrial crocodylomorphs Late Cretaceous crocodylomorphs of South America Maastrichtian life Cretaceous Brazil Fossils of Brazil Marília Formation Fossil taxa described in 1955 Prehistoric pseudosuchian genera {{paleo-archosaur-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Baurusuchidae
Baurusuchidae is a Gondwanan family of mesoeucrocodylians that lived during the Late Cretaceous. It is a group of terrestrial hypercarnivorous crocodilians from South America (Argentina and Brazil) and possibly Pakistan. Baurusuchidae has been, in accordance with the PhyloCode, officially defined as the least inclusive clade containing ''Cynodontosuchus rothi, Pissarrachampsa sera,'' and ''Baurusuchus pachecoi.'' Baurusuchids have been placed in the suborder Baurusuchia, and two subfamilies have been proposed: Baurusuchinae and Pissarrachampsinae. Genera Several genera have been assigned to Baurusuchidae. ''Baurusuchus'' was the first, being the namesake of the family. Remains of ''Baurusuchus'' have been found from the Late Cretaceous Bauru Group of Brazil in deposits that are Turonian - Santonian in age. In addition to ''Baurusuchus'', five other South American crocodyliforms have been assigned to Baurusuchidae: ''Campinasuchus'', ''Cynodontosuchus'', ''Pissarrachampsa'', ''Stra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Barcinosuchus
''Barcinosuchus'' (meaning "Cerro Barcino Formation's crocodile") is an extinct genus of carnivorous metasuchian from the early Cretaceous period. It is a peirosaurid which lived during the early Cretaceous period (Aptian to Albian stage) in what is now Chubut Province, Argentina. It is known from the holotype MPEF-PV 3095, which consists of skull, mandible, and postcranial remains. The specimen recovered from the lower part of the Cerro Castaño Member of the Cerro Barcino Formation. ''Barcinosuchus'' was named by Martín Leardi and Diego Pol in 2009 and 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 specimen ... is ''Barcinosuchus gradilis''. References Terrestrial crocodylomorphs Albian life Aptian life Early Cretaceous crocodylomorphs of South America ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Early Jurassic
The Early Jurassic Epoch (geology), Epoch (in chronostratigraphy corresponding to the Lower Jurassic series (stratigraphy), Series) is the earliest of three epochs of the Jurassic Period. The Early Jurassic starts immediately after the Triassic-Jurassic extinction event, 201.3 Ma (million years ago), and ends at the start of the Middle Jurassic 174.1 Ma. Certain rocks of marine origin of this age in Europe are called "Lias Group, Lias" and that name was used for the period, as well, in 19th-century geology. In southern Germany rocks of this age are called Black Jurassic. Origin of the name Lias There are two possible origins for the name Lias: the first reason is it was taken by a geologist from an England, English quarryman's dialect pronunciation of the word "layers"; secondly, sloops from north Cornwall, Cornish ports such as Bude would sail across the Bristol Channel to the Vale of Glamorgan to load up with rock from coastal limestone quarries (lias limestone from S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Araripesuchus Wegeneri
''Araripesuchus'' is a genus of extinct crocodyliform that existed during the Cretaceous period of the late Mesozoic era some 125 to 66 million years ago. Six species of ''Araripesuchus'' are currently known. They are generally considered to be notosuchians (belonging to the clade Mesoeucrocodylia), characterized by their varied teeth types and distinct skull elements. This genus consists of six species: ''A. buitreraensis'', discovered in Argentina, ''A. wegeneri'', discovered in Cameroon and Niger, ''A. rattoides'', discovered in Niger, ''A. tsangatsangana'', discovered in Madagascar, ''A. gomesii'' (the type species), discovered in Brazil and another species discovered in Argentina, ''A. patagonicus''. Description Its length was about with a weight of . ''Araripesuchus'' can be distinguished by their laterally bulged edges of the snout, with the bulge being the most prominent around the area of an enlarged maxillary tooth. The snout and premaxilla are also smoother than tha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Maximum Parsimony (phylogenetics)
In phylogenetics, maximum parsimony is an optimality criterion under which the phylogenetic tree that minimizes the total number of character-state changes (or miminizes the cost of differentially weighted character-state changes) is preferred. Under the maximum-parsimony criterion, the optimal tree will minimize the amount of homoplasy (i.e., convergent evolution, parallel evolution, and evolutionary reversals). In other words, under this criterion, the shortest possible tree that explains the data is considered best. Some of the basic ideas behind maximum parsimony were presented by James S. Farris in 1970 and Walter M. Fitch in 1971. Maximum parsimony is an intuitive and simple criterion, and it is popular for this reason. However, although it is easy to ''score'' a phylogenetic tree (by counting the number of character-state changes), there is no algorithm to quickly ''generate'' the most-parsimonious tree. Instead, the most-parsimonious tree must be sought in "tree space" ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Baurusuchus
''Baurusuchus'' is an extinct member of the ancestral crocodilian lineage, which lived in Brazil from 90 to 83.5 million years ago, in the Late Cretaceous period. Technically, it is a genus of baurusuchid mesoeucrocodylian. It was a terrestrial predator and scavenger, about long and in weight. ''Baurusuchus'' lived during the Turonian to Santonian stages of the Late Cretaceous Period, in Adamantina Formation, Brazil. It gets its name from the Brazilian Bauru Group ("Bauru crocodile"). It was related to the earlier-named ''Cynodontosuchus rothi'', which was smaller, with weaker dentition. The three species are ''B. pachechoi'', named after Eng Joviano Pacheco, its discoverer, ''B. salgadoensis'' (named after General Salgado County in São Paulo, Brazil) and ''B. albertoi'' (named after Alberto Barbosa de Carvalho, Brazilian paleontologist). The latter species is disputed (see phylogeny section). Its relatives include the similarly sized ''Stratiotosuchus'' from the Adamanti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polyphyletic
A polyphyletic group is an assemblage of organisms or other evolving elements that is of mixed evolutionary origin. The term is often applied to groups that share similar features known as homoplasies, which are explained as a result of convergent evolution. The arrangement of the members of a polyphyletic group is called a polyphyly .. ource for pronunciation./ref> It is contrasted with monophyly and paraphyly. For example, the biological characteristic of warm-bloodedness evolved separately in the ancestors of mammals and the ancestors of birds; "warm-blooded animals" is therefore a polyphyletic grouping. Other examples of polyphyletic groups are algae, C4 photosynthetic plants, and edentates. Many taxonomists aim to avoid homoplasies in grouping taxa together, with a goal to identify and eliminate groups that are found to be polyphyletic. This is often the stimulus for major revisions of the classification schemes. Researchers concerned more with ecology than with systema ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sebecidae
Sebecidae is an extinct family of prehistoric terrestrial 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 th ...n crocodylomorphs. The oldest known member of the group is ''Ogresuchus furatus'' known from the Upper Cretaceous (Maastrichtian) Tremp Formation (Spain). Sebecids were diverse, abundant and broadly distributed in South America (mostly in Argentina, Brazil and Bolivia) during the Cenozoic, until the Middle Miocene; although it has been suggested that at least some forms could have survived until the Miocene-Pliocene boundary in Brazil. This group included many medium- and large-sized Genus, genera, from ''Sebecus'' to a giant indeterminate unnamed species from the Miocene. Phylogeny The following cladogram simplified after Diego Pol and Jaime E. Powell (2011). ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sebecia
Sebecia is an extinct clade of mesoeucrocodylian crocodyliforms that includes peirosaurids and sebecids. It was first constructed in 2007 to include ''Hamadasuchus'', Peirosauridae, and ''Sebecus''. It was initially considered to be the sister taxon of the clade Neosuchia, which includes living crocodilians, although some later studies have placed it within Neosuchia as a basal clade. Sebecians were terrestrial crocodyliforms characterized by their deep snouts and ziphodont dentition. They first appeared in the Late Cretaceous, survived the Cretaceous–Paleogene extinction event, and became extinct in the Miocene epoch. According to paleontologists Hans Larsson and Hans-Dieter Sues, who constructed the clade in 2007, Sebecia also includes genera that were once assigned to Baurusuchidae, namely ''Pabwehshi''. However, other baurusuchids, namely ''Baurusuchus'', were placed outside Sebecia. Therefore, Baurusuchidae was considered polyphyletic and thus not a true clade. Below is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mahajangasuchidae
Mahajangasuchidae is an extinct family of notosuchian crocodyliforms. It currently contains two genera, '' Mahajangasuchus'' and '' Kaprosuchus'', both of which lived during the Late Cretaceous in Gondwana. It is defined as the most inclusive clade containing ''Mahajangasuchus insignis'' but not ''Notosuchus terrestris'', '' Simosuchus clarki'', '' Araripesuchus gomesii'', ''Baurusuchus pachecoi'', '' Peirosaurus torminni'', '' Goniopholis crassidens'', '' Pholidosaurus schaumbergensis'', or ''Crocodylus niloticus''. Phylogenetically, Mahajangasuchidae is placed just outside pholidosaurids and more derived neosuchians. Defining characters of the family include fused nasals, a jaw articulation below the posterior maxillary tooth row, a deep mandibular symphysis that is oriented anterodorsally, and the formation of a hornlike posterodorsal process from the squamosal and parietal (which is much more pronounced in ''Kaprosuchus''). Phylogeny Cladogram showing the phylogenetic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
