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Dakosaurus Nicaeensis
''Aggiosaurus'' is an extinct genus of geosaurine metriorhynchid crocodyliform known from the Late Jurassic (late Oxfordian stage) of Nice, southeastern France. It contains a single species, ''Aggiosaurus nicaeensis'', which was named by H. Ambayrac in 1913.H. Ambayrac. (1913). Découverte d'une mâchoire de reptile jurassique iscovery of a jaw from a Jurassic reptile ''Bulletin Mensuel des Naturalistes des Alpes-Maritimes'' 15:65-68 History of discovery ''Aggiosaurus'' is known only from its holotype, an unnumbered, poorly preserved upper jaw collected by H. Ambayrac in 1912, Maury, E. (1915). New observations on the Jurassic reptile localities on the road from Cap d'Ail to La Turbie. ''Riviera Scientifique. Bulletin de l'Association des Naturalistes de Nice et des Alpes-Maritimes'' 2(1):4-6 preserved in limestone which is now housed in the Muséum d'histoire naturelle de Nice. It was collected from the late Oxfordian-aged locality of Cap d’Aggio-La Turbie, in Nice, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Late Jurassic
The Late Jurassic is the third epoch of the Jurassic Period, and it spans the geologic time from 163.5 ± 1.0 to 145.0 ± 0.8 million years ago (Ma), which is preserved in Upper Jurassic strata.Owen 1987. In European lithostratigraphy, the name "Malm" indicates rocks of Late Jurassic age. In the past, ''Malm'' was also used to indicate the unit of geological time, but this usage is now discouraged to make a clear distinction between lithostratigraphic and geochronologic/chronostratigraphic units. Subdivisions The Late Jurassic is divided into three ages, which correspond with the three (faunal) stages of Upper Jurassic rock: Paleogeography During the Late Jurassic Epoch, Pangaea broke up into two supercontinents, Laurasia to the north, and Gondwana to the south. The result of this break-up was the spawning of the Atlantic Ocean. However, at this time, the Atlantic Ocean was relatively narrow. Life forms of the epoch This epoch is well known for many famous types of din ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Megalosaurid
Megalosauridae is a monophyletic family of carnivorous theropod dinosaurs within the group Megalosauroidea. Appearing in the Middle Jurassic, megalosaurids were among the first major radiation of large theropod dinosaurs. They were a relatively primitive group of basal tetanurans containing two main subfamilies, Megalosaurinae and Afrovenatorinae, along with the basal genus '' Eustreptospondylus'', an unresolved taxon which differs from both subfamilies. The defining megalosaurid, '' Megalosaurus bucklandii'', was first named and described in 1824 by William Buckland after multiple finds in Stonesfield, Oxfordshire, UK. ''Megalosaurus'' was the first formally described dinosaur and was the basis for the establishment of the clade Dinosauria. It is also one of the largest known Middle Jurassic carnivorous dinosaurs, with the best-preserved femur at 805 mm and a proposed body mass of around 943 kg. Megalosauridae has mainly been recognized as a European group of din ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ancient Greek
Ancient Greek includes the forms of the Greek language used in ancient Greece and the ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek (), Dark Ages (), the Archaic period (), and the Classical period (). Ancient Greek was the language of Homer and of fifth-century Athenian historians, playwrights, and philosophers. It has contributed many words to English vocabulary and has been a standard subject of study in educational institutions of the Western world since the Renaissance. This article primarily contains information about the Epic and Classical periods of the language. From the Hellenistic period (), Ancient Greek was followed by Koine Greek, which is regarded as a separate historical stage, although its earliest form closely resembles Attic Greek and its latest form approaches Medieval Greek. There were several regional dialects of Ancient Greek, of which Attic Greek developed into Koi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Name Of A Biological Genus
Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nomenclature, the genus name forms the first part of the binomial species name for each species within the genus. :E.g. '' Panthera leo'' (lion) and '' Panthera onca'' (jaguar) are two species within the genus ''Panthera''. ''Panthera'' is a genus within the family Felidae. The composition of a genus is determined by taxonomists. The standards for genus classification are not strictly codified, so different authorities often produce different classifications for genera. There are some general practices used, however, including the idea that a newly defined genus should fulfill these three criteria to be descriptively useful: # monophyly – all descendants of an ancestral taxon are grouped together (i.e. phylogenetic analysis should clearly demo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Homoplasy
Homoplasy, in biology and phylogenetics, is the term used to describe a feature that has been gained or lost independently in separate lineages over the course of evolution. This is different from homology, which is the term used to characterize the similarity of features that can be parsimoniously explained by common ancestry. Homoplasy can arise from both similar selection pressures acting on adapting species, and the effects of genetic drift. Most often, homoplasy is viewed as a similarity in morphological characters. However, homoplasy may also appear in other character types, such as similarity in the genetic sequence, life cycle types or even behavioral traits. Etymology The term homoplasy was first used by Ray Lankester in 1870. The corresponding adjective is either ''homoplasic'' or ''homoplastic''. It is derived from the two Ancient Greek words (), meaning "similar, alike, the same", and (), meaning "to shape, to mold". Parallelism and convergence Parallel a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geosaurini
Geosaurinae is a subfamily of metriorhynchid crocodyliforms from the Middle Jurassic to the Early Cretaceous (Bathonian - Aptian) of Europe, North America and South America. Named by Richard Lydekker, in 1889, it contains the metriorhynchids ''Suchodus'', '' Purranisaurus'', '' Neptunidraco'', '' Tyrannoneustes'', '' Torvoneustes'', '' Dakosaurus'', ''Geosaurus'' and '' Plesiosuchus''. The last four taxa form a tribe within Geosaurinae, the Geosaurini. Geosaurinae is one of two subfamilies of Metriorhynchidae, the other being Metriorhynchinae. These marine reptiles were widespread during the Late Jurassic and Early Cretaceous, their fossilized remains are being frequently found on various places around the world.Daniel Madzia, Sven Sachs, Mark T. Young, Alexander Lukeneder and Petr Skupien (2021)Evidence of two lineages of metriorhynchid crocodylomorphs in the Lower Cretaceous of the Czech Republic ''Acta Palaeontologica Polonica''. doi: https://doi.org/10.4202/app.00801.2020 Ph ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Basal (phylogenetics)
In phylogenetics, basal is the direction of the ''base'' (or root) of a rooted phylogenetic tree or cladogram. The term may be more strictly applied only to nodes adjacent to the root, or more loosely applied to nodes regarded as being close to the root. Note that extant taxa that lie on branches connecting directly to the root are not more closely related to the root than any other extant taxa. While there must always be two or more equally "basal" clades sprouting from the root of every cladogram, those clades may differ widely in taxonomic rank, species diversity, or both. If ''C'' is a basal clade within ''D'' that has the lowest rank of all basal clades within ''D'', ''C'' may be described as ''the'' basal taxon of that rank within ''D''. The concept of a 'key innovation' implies some degree of correlation between evolutionary innovation and diversification. However, such a correlation does not make a given case predicable, so ancestral characters should not be imputed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paraphyletic
In taxonomy (general), taxonomy, a group is paraphyletic if it consists of the group's most recent common ancestor, last common ancestor and most of its descendants, excluding a few Monophyly, monophyletic subgroups. The group is said to be paraphyletic ''with respect to'' the excluded subgroups. In contrast, a monophyletic group (a clade) includes a common ancestor and ''all'' of its descendants. The terms are commonly used in phylogenetics (a subfield of biology) and in the tree model of historical linguistics. Paraphyletic groups are identified by a combination of Synapomorphy and apomorphy, synapomorphies and symplesiomorphy, symplesiomorphies. If many subgroups are missing from the named group, it is said to be polyparaphyletic. The term was coined by Willi Hennig to apply to well-known taxa like Reptilia (reptiles) which, as commonly named and traditionally defined, is paraphyletic with respect to mammals and birds. Reptilia contains the last common ancestor of reptiles a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plesiosuchus
''Plesiosuchus'' is an extinct genus of geosaurine metriorhynchid crocodyliform known from the Late Jurassic (late Kimmeridgian to early Tithonian stage) of Dorset, England and possibly also Spain. It contains a single species, ''Plesiosuchus manselii''. Discovery The type and referred specimens of ''Plesiosuchus'' were discovered by John Clavell Mansel-Pleydell in the 1860s alongside the remains of several other large-bodied marine reptiles along the coast of Dorset. Mansel-Pleydell gave these remains to the British Museum (now in the Natural History Museum) in 1866. Part of the holotype of ''P. manselii'' (NHMUK PV OR40103a) was first described by John Hulke in 1869. He referred it to ''Steneosaurus rostro-minor'' Geoffroy (1825), alongside ''Dakosaurus maximus'' and other specimens. Initially, the skull (NHMUK PV OR40103) was believed to be pliosaurian; it was the preparator Mr Davies that suggested a crocodylian nature for the skull. In 1870, Hulke ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Torvoneustes
''Torvoneustes'' is an extinct genus of metriorhynchid thalattosuchian. It is known from skull and postcranial remains found in the Kimmeridge Clay Formation of Dorset and Wiltshire, England, and also from Oaxaca, Mexico . The holotype skull of the type species was initially assigned to the species '' Metriorhynchus superciliosus''. Postcranial remains were later discovered from the same quarry as the skull, and then these specimens were recognised as belonging to a new species of '' Dakosaurus'', as ''D. carpenteri''. The species was named to honour Simon Carpenter, an amateur geologist from Frome in Somerset, who discovered the fossils. ''Dakosaurus carpenteri'' was later reassigned to the genus ''Geosaurus'' in 2008. Two years later, it was assigned to its own genus, ''Torvoneustes''. When ''T. carpenteri'' was considered a species of ''Dakosaurus'', its relatively long snout and smaller, more numerous teeth were thought to be features retained from more basal metriorhynch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 of organisms. These relationships are determined by Computational phylogenetics, phylogenetic inference methods that focus on observed heritable traits, such as DNA sequences, protein amino acid sequences, or morphology. The result of such an analysis is a phylogenetic tree—a diagram containing a hypothesis of relationships that reflects the evolutionary history of a group of organisms. The tips of a phylogenetic tree can be living taxa or fossils, and represent the "end" or the present time in an evolutionary lineage. A phylogenetic diagram can be rooted or unrooted. A rooted tree diagram indicates the hypothetical common ancestor of the tree. An unrooted tree diagram (a network) makes no assumption about the ancestral line, and does ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thalattosuchia
Thalattosuchia is a clade of marine crocodylomorphs from the Early Jurassic to the Early Cretaceous that had a cosmopolitan distribution. They are colloquially referred to as marine crocodiles or sea crocodiles, though they are not members of Crocodilia and records from Thailand and China suggest that some members lived in freshwater. The clade contains two major subgroupings, the Teleosauroidea and Metriorhynchoidea. Teleosauroids are not greatly specialised for oceanic life, with back osteoderms similar to other crocodyliformes. Within Metriorhynchoidea, the Metriorhynchidae displayed extreme adaptions for life in the open ocean, including the transformation of limbs into flippers, the development of a tail fluke, and smooth, scaleless skin. Discovery and naming The term Thalattosuchia was coined by Fraas in 1901.Fraas E. 1901. Die Meerkrokodile (Thalattosuchia n. g.) eine neue Sauriergruppe der Juraformation. ''Jahreshefte des Vereins für vaterländische Naturkunde, Wür ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
