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39-712: Grypoceratidae is the longest-lived family of the Trigonoceratoidea , or of the near equivalent Centroceratina ; members of the Nautilida from the Upper Paleozoic and Triassic . The Grypoceratidae are characterized by evolute to involute shells that may have some modification to the venter (the outer rim) varying from flattened to subangular , or bearing a keel. Most are smooth but some have nodes or carinae (auxiliary keels). Sutures generally have distinct ventral and lateral lobes but in some,

78-631: A conodont, Misikella posthernsteini . As of 2010 , the base of the Norian has not yet been established, but will likely be based on conodonts. The late Triassic is also divided into land-vertebrate faunachrons . These are, from oldest to youngest, the Berdyankian , Otischalkian , Adamanian , Revueltian and Apachean . Following the Permian–Triassic extinction event , surviving organisms diversified. On land, archosauriforms , most notably

117-457: A consensus over time. The naming of families is codified by various international bodies using the following suffixes: The taxonomic term familia was first used by French botanist Pierre Magnol in his Prodromus historiae generalis plantarum, in quo familiae plantarum per tabulas disponuntur (1689) where he called the seventy-six groups of plants he recognised in his tables families ( familiae ). The concept of rank at that time

156-479: A deep ventral lobe; Pselioceras , a smooth evolute form with a perforate umbilicus , ovoid whorl section, and suture crossing straight over the venter; and Virgaloceras , also similar to Domatoceras but with a row of nodes on the umbilical wall and a ventral saddle instead of the ventral lobe in the suture. Parastenopoceras , Plummeroceras , and Pselioceras are from the Lower Permian; Virgaloceras

195-446: A family, yet in the realm of plants, these classifications often rely on both the vegetative and reproductive characteristics of plant species. Taxonomists frequently hold varying perspectives on these descriptions, leading to a lack of widespread consensus within the scientific community for extended periods. The continual publication of new data and diverse opinions plays a crucial role in facilitating adjustments and ultimately reaching

234-577: A shallow ventral lobe and siphuncle positioned against the venter. Gryponautilus from the Upper Triassic is broadly involute with a narrowly rounded, keel-like venter at maturity and shallow ventral and lateral lobes in the suture. All members of the Grypoceratidae have a ventral lobe with the exception of Stenoporceras , Parastenopoceras , and Virgaloceras , which have a ventral saddle instead. The derivation of these three within

273-546: A type of large scale volcanic activity that releases a huge volume of lava in addition to sulfur dioxide and carbon dioxide. The sudden increase in carbon dioxide levels is believed to have enhanced the greenhouse effect , which acidified the oceans and raised average air temperature. As a result of the change in biological conditions in the oceans, 22% of marine families became extinct. In addition, 53% of marine genera and about 76–86% of all species became extinct, which vacated ecological niches; thus, enabling dinosaurs to become

312-471: A ventral saddle. Whorl sections are generally compressed but may be subquadrate to subtrapezoidal or coronate (heart shaped), or slightly depressed dorso-ventrally. The Grypoceratidae begin with Epidomatodceras from the Lower Carboniferous (Mississippian), an evolute form with a smooth shell, subquadrate whorl section, and a sharp angular ventral lobe in the suture. Epidomatoceras

351-476: A year. The epoch had a fluctuating, warm climate in which it was occasionally marked by instances of powerful heat. Different basins in certain areas of Europe provided evidence of the emergence of the "Middle Carnian Pluvial Event." For example, the Western Tethys and German Basin was defined by the theory of a middle Carnian wet climate phase. This event stands as the most distinctive climate change within

390-858: Is followed by Domatoceras , Paradomatoceras , Stearoceras , Stenopoceras , and Titanoceras from the Upper Carboniferous (Pennsylvanian) and Lower Permian . Domatoceras , Paradomatoceras , and Titanoceras are rather similar in that they are somewhat large, evolute with whorls in contact but not deeply impressed along the inner margin of the whorls, and with straight flanks and flattened venters. Whorl sections vary from strongly compressed side to side with height much greater than width in Paradomatoceras to slightly depressed with height less than width in Titanoceras , with Domatoceras subquadrate in between. Stearoceras

429-668: Is from the Upper Permian . The last three genera are from the Triassic , none having crossed from the Permian. Grypoceras , given simply a Triassic, is like Domatoceras but tending to be more involute and to have more rounded ventral shoulders. Menuthionautilus from the Lower Triassic has a rapidly expanding, smooth involute shell with a deep dorsal impression, broadly convex flanks and rounded venter, suture with

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468-456: Is involute with a depressed subtrapizoidal whorl section and slight ventral and lateral lobes. Stenoporceras is subdiscoidal, flattened laterally, and has a suture with broad lateral lobes and a deep ventral saddle as found in syringonautilids . Permian genera include Parastenopoceras , a smooth, involute form with a semiellptical whorl section and ventral saddle; Plummeroceras , a form similar to Domatoceras but more evolute and with

507-476: The Genera Plantarum of George Bentham and Joseph Dalton Hooker this word ordo was used for what now is given the rank of family. Families serve as valuable units for evolutionary, paleontological, and genetic studies due to their relatively greater stability compared to lower taxonomic levels like genera and species. Upper Triassic Many of the first dinosaurs evolved during

546-538: The dinosaurs became an important faunal component in the Late Triassic. Likewise, bony fishes diversified in aquatic environments, most notably the Neopterygii , to which nearly all extant species of fish belong. Among the neopterygians, stem-group teleosts and the now extinct Pycnodontiformes became more abundant in the Late Triassic. The Carnian is the first age of the Late Triassic, covering

585-1009: The Centroceratina into two superfamilies, the Tribolocerataceae with one family and the Centrocerataceae with six families. Among the Centroceratacea the Domatoceratidae and Grypoceratidae (sensu Shimansky) are equivalent to the Gypoceratidae of the Treatise. The Domatoceratidae which include forms with ventral lobes and ventral saddles extends from the Carboniferous barely into the Triassic. The Grypoceratidae of Shimansky contains

624-596: The Grypoceratidae is uncertain. Stenopoceras or Parastenopoceras is the likely ancestor of the Syringonautilidae from the Triassic. The taxonomy of the Grypoceratidae in the Treatise on Invertebrate Paleontology is straightforward with no attempt to define subdivisions within the family. The taxonomy of the Centroceratina of Shimansky (1962) in Kummel (1964) is more involved. Shimansky first of all divided

663-634: The Late Triassic Epoch did not prove to be as destructive as the preceding Permian Period, which took place approximately 50 million years earlier and destroyed about 70% of land species, 57% of insect families as well as 95% of marine life , it resulted in great decreases in population sizes of many living organism populations. The environment of the Late Triassic had negative effects on the conodonts and ammonoid groups. These groups once served as vital index fossils , which made it possible to identify feasible life span to multiple strata of

702-474: The Late Triassic, including Plateosaurus , Coelophysis , Herrerasaurus , and Eoraptor . The Triassic–Jurassic extinction event began during this epoch and is one of the five major mass extinction events of the Earth. The Triassic was named in 1834 by Friedrich von Alberti , after a succession of three distinct rock layers (Greek triás meaning 'triad') that are widespread in southern Germany :

741-448: The Late Triassic. Conclusions summarized that the correlation of these sediments led to the modified version of the new map of Central Eastern Pangea, as well as that the sediment's relation to the "Carnian Pluvial Event" is greater than expected. The extinction event that began during the Late Triassic resulted in the disappearance of about 76% of all terrestrial and marine life species, as well as almost 20% of taxonomic families. Although

780-538: The Triassic Period. Sediments that include red beds, which are sandstones and shales of color, may suggest seasonal precipitation. Rocks also included dinosaur tracks, mudcracks, and fossils of crustaceans and fish, which provide climate evidence, since animals and plants can only live during periods of which they can survive through. The Late Triassic is described as semiarid. Semiarid is characterized by light rainfall, having up to 10–20 inches of precipitation

819-454: The Triassic Period. Propositions for its cause include: Theories and concepts are supported universally, due to extensive areal proof of Carnian siliciclastic sediments. The physical positions as well as comparisons of that location to surrounding sediments and layers stood as basis for recording data. Multiple resourced and recurring patterns in results of evaluations allowed for the satisfactory clarification of facts and common conceptions on

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858-556: The Triassic genera of Kummel's larger Grypoceraidae and are derived, probably in the Late Permian, from the more restricted Domatoceratidae. Family (taxonomy) Family ( Latin : familia , pl. : familiae ) is one of the eight major hierarchical taxonomic ranks in Linnaean taxonomy . It is classified between order and genus . A family may be divided into subfamilies , which are intermediate ranks between

897-503: The Triassic strata. These groups were severely affected during the epoch, and conodonts became extinct soon after (in the earliest Jurassic). Despite the large populations that withered away with the coming of the Late Triassic, many families, such as the pterosaurs , crocodiles , mammals and fish were very minimally affected. However, such families as the bivalves, gastropods , marine reptiles and brachiopods were greatly affected and many species became extinct during this time. Most of

936-514: The book's morphological section, where he delved into discussions regarding the vegetative and generative aspects of plants. Subsequently, in French botanical publications, from Michel Adanson 's Familles naturelles des plantes (1763) and until the end of the 19th century, the word famille was used as a French equivalent of the Latin ordo (or ordo naturalis ). In zoology ,

975-530: The dominant presence in the Jurassic Period. While the majority of the scientists agree that volcanic activity was the main cause of the extinction, other theories suggest the extinction was triggered by the impact of an asteroid, climate change, or rising sea levels . The impacts that the Late Triassic had on surrounding environments and organisms were wildfire destruction of habitats and prevention of photosynthesis. Climatic cooling also occurred due to

1014-544: The end of the period, continental drift occurred which separated Pangea. At this time, polar ice was not present because of the large differences between the equator and the poles. A single, large landmass similar to Pangea would be expected to have extreme seasons; however, evidence offers contradictions. Evidence suggests that there is arid climate as well as proof of strong precipitation. The planet's atmosphere and temperature components were mainly warm and dry, with other seasonal changes in certain ranges. The Middle Triassic

1053-588: The evidence suggests the increase of volcanic activity was the main cause of the extinction. As a result of the rifting of the super continent Pangea , there was an increase in widespread volcanic activity which released large amounts of carbon dioxide. At the end of the Triassic Period, massive eruptions occurred along the rift zone , known as the Central Atlantic Magmatic Province , for about 500,000 years. These intense eruptions were classified as flood basalt eruptions, which are

1092-540: The family as a rank intermediate between order and genus was introduced by Pierre André Latreille in his Précis des caractères génériques des insectes, disposés dans un ordre naturel (1796). He used families (some of them were not named) in some but not in all his orders of "insects" (which then included all arthropods ). In nineteenth-century works such as the Prodromus of Augustin Pyramus de Candolle and

1131-541: The first dinosaurs came at about the same time as the Carnian pluvial episode , at 234 to 232 Ma. This was a humid interval in the generally arid Triassic. It was marked by high extinction rates in marine organisms, but may have opened niches for the radiation of the dinosaurs. The Norian is the second age of the Late Triassic, covering the time interval from about 227 to 208.5 million years ago. During this age, herbiverous sauropodomorphs diversified and began to displace

1170-435: The large herbivorous therapsids , perhaps because they were better able to adapt to the increasingly arid climate. However crurotarsans continued to occupy more ecological niches than dinosaurs. In the oceans, neopterygian fish proliferated at the expense of ceratitid ammonites. The Manicouagan impact event occurred 214 million years ago. However, no extinction event is associated with this impact. The Rhaetian Age

1209-516: The lower Buntsandstein (colourful sandstone ) , the middle Muschelkalk (shell-bearing limestone) and the upper Keuper (coloured clay). The Late Triassic Series corresponds approximately to the middle and upper Keuper. On the geologic time scale , the Late Triassic is usually divided into the Carnian, Norian, and Rhaetian ages, and the corresponding rocks are referred to as the Carnian, Norian, and Rhaetian stages. Triassic chronostratigraphy

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1248-428: The ocean, as well as some organisms known for reef -building, and the pelagic conodonts . In addition to these species that became extinct, the straight-shelled nautiloids , placodonts , bivalves , and many types of reptile did not survive through this age. During the beginning of the Triassic Period, the Earth consisted of a giant landmass known as Pangea, which covered about a quarter of Earth's surface. Towards

1287-491: The ranks of family and genus. The official family names are Latin in origin; however, popular names are often used: for example, walnut trees and hickory trees belong to the family Juglandaceae , but that family is commonly referred to as the "walnut family". The delineation of what constitutes a family— or whether a described family should be acknowledged— is established and decided upon by active taxonomists . There are not strict regulations for outlining or acknowledging

1326-482: The soot in the atmosphere. Studies also show that 103 families of marine invertebrates became extinct at the end of the Triassic, but another 175 families lived on into the Jurassic. Marine and extant species were hit fairly hard by extinctions during this epoch. Almost 20% of 300 extant families became extinct; bivalves, cephalopods, and brachiopods suffered greatly. 92% of bivalves were wiped out episodically throughout

1365-400: The time interval from 237 to 227 million years ago. The earliest true dinosaurs likely appeared during the Carnian and rapidly diversified. They emerged in a world dominated by crurotarsan archosaurs (ancestors of crocodiles ), predatory phytosaurs , herbivorous armored aetosaurs , and giant carnivorous rauisuchians , which the dinosaurs gradually began to displace. The emergence of

1404-425: Was known to have consistent intervals of high levels of humidity. The circulation and movement of these humidity patterns, geographically, are not known however. The major Carnian Pluvial Event stands as one focus point of many studies. Different hypotheses of the events occurrence include eruptions, monsoonal effects, and changes caused by plate tectonics. Continental deposits also support certain ideas relative to

1443-488: Was not yet settled, and in the preface to the Prodromus Magnol spoke of uniting his families into larger genera , which is far from how the term is used today. In his work Philosophia Botanica published in 1751, Carl Linnaeus employed the term familia to categorize significant plant groups such as trees , herbs , ferns , palms , and so on. Notably, he restricted the use of this term solely within

1482-512: Was originally based on ammonite fossils, beginning with the work of Edmund von Mojsisovics in the 1860s. The base of the Late Triassic (which is also the base of the Carnian) is set at the first appearance of an ammonite, Daxatina canadensis . In the 1990s, conodonts became increasingly important in the Triassic timescale, and the base of the Rhaetian is now set at the first appearance of

1521-488: Was the final age of the Late Triassic, following the Norian Age, and it included the last major disruption of life until the end-Cretaceous mass extinction . This age of the Triassic is known for its extinction of marine reptiles , such as nothosaurs and shastasaurs with the ichthyosaurs , similar to today's dolphin . This age was concluded with the disappearance of many species that removed types of plankton from

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