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Hecticoceratinae
Hecticoceratinae is a subfamily of oppeliids from the Middle and Upper Jurassic typically with strong falcoid or falcate ribbing that covers whorl sides completely. Venters are usually keeled and may be tricarinate.Treatise on Invertebrate Paleontology Part L, ''L276'' (Ammonoidea) The Hecticocerainae, which has its origin in the Oppeliinae, give rise to the Distichoceratinae near the beginning of the Middle Jurassic Callovian, and to the Glochiceratinae early in the Upper Jurassic Oxfordian.Classification of Jurassic Ammonitina, D.T. Donovan, et al., Systematics Assoc., 1981 Neither apparently gave rise to any subsequent groups. Genera ''Hecticoceras'', ''Brightia'', ''Eochetoceras'', ''Hecticoceratoides'', ''Lunuloceras'', ''Kheraites'', ''Proheticoceras'', ''Pseudobrightia'', and ''Pseudobrightia'', listed as separate genera in the Treatise are regarded as subgenera of ''Hecticoceras ''Hecticoceras'' is an ammonite genus belonging to the haploceratoid family Oppeliid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oppeliidae
Oppeliidae are compressed to oxyconic, sculptured Haploceratoidea, either unkeeled, unicarinate, bicarinate, or tricarinate; with sutures in great variety, but ribbing usually more or less falcoid or falcate. The Oppeliidae is the principal family of the Haploceratoidea, with the longest duration, extending from the Middle Jurassic (Bajocian) to the Upper Cretaceous (Cenomanian) Their derivation is from the Hildoceratoidea. Subfamilies Nine subfamilies are recognized, the first eight of which are included in the earlier Treatise, Part L. They are the: :Oppeliinae :Hecticoceratinae :Distchoceratinae :Teramelliceratinae :Phlycticeratinae :Streblitinae :Mazapilitinae :Aconeceratinae :Binneyitinae The Binneyitinae was added by Donovan ''et al'', 1981, transferred from the Stephanoceratoidea. References * D.T Donavan, J.H. Callomon, and M.K Howarth. 1981. Classification of the Jurassic Ammonitina. In The Ammonoidea. M.R. House and J.R. Senior, eds. Systematics Assoc. Pub Acad ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oppeliinae
Oppeliinae is a subfamily within the Oppeliidae, a family of Jurassic ammonites characterized by forms that are mainly oxyconic, compressed with sharp venters, in the adult and with keeled inner whorls. Sutures are complex, consisting of a long series of evenly graded lobes and saddles with finely frilled endings.Treatise on Invertebrate Paleontology Part L ''L274'',(Ammonoidea) The Oppeliinae gave rise to the Hecticoceratinae in the early Bathonian stage, near the middle of their range and to the Taramelliceratinae, in the late Callovian, near the end of their tange, which in turn gave rise to the Streblitinae in the early Kimmeridgian and to the Haploceratidae in the late Kimmeridgian.Classification of Jurassic Ammonitina, D.T. Donovan, ''et al.'' Systematics Assoc no 18 Distribution is worldwide, from the Middle Jurassic, except for Boreal regions. List of genera The Oppeliinae includes the following genera, listed in order of appearance. :'' Bradfordia'' :''Oppelia'' :''O ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hecticoceras
''Hecticoceras'' is an ammonite genus belonging to the haploceratoid family Oppeliidae, that lived during the Middle and Late Jurassic, from the Callovian. ''Hecticoceras'' may be seen as a series of some nine subgenera, beginning with the lower Callovian ''H. (Hecticoceras)'' and ''H. (Hecticoceratoides)'' and ending with the lower Oxfordian ''H. (Pseudobrightia)'' and ''H. (Eochetoceras)''. ''Hecticoceras'' ''sensu lato'' and ''Prohecticoceras'' from the underlying Bathonian In the geologic timescale the Bathonian is an age and stage of the Middle Jurassic. It lasted from approximately 168.3 Ma to around 166.1 Ma (million years ago). The Bathonian Age succeeds the Bajocian Age and precedes the Callovian Age. Strat ... form the oppeliid subfamily, Hecticoceratinae. ''Hecticoceras'', including its various subgenera, have a widespread distribution and have been found in the late Middle and early Upper Jurassic of Europe, North Africa, Somalia, India, Madagascar, and possib ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jurassic
The Jurassic ( ) is a Geological period, geologic period and System (stratigraphy), stratigraphic system that spanned from the end of the Triassic Period million years ago (Mya) to the beginning of the Cretaceous Period, approximately Mya. The Jurassic constitutes the middle period of the Mesozoic, Mesozoic Era and is named after the Jura Mountains, where limestone strata from the period were first identified. The start of the Jurassic was marked by the major Triassic–Jurassic extinction event, associated with the eruption of the Central Atlantic magmatic province, Central Atlantic Magmatic Province. The beginning of the Toarcian Stage started around 183 million years ago and is marked by an extinction event associated with widespread Anoxic event, oceanic anoxia, ocean acidification, and elevated temperatures likely caused by the eruption of the Karoo-Ferrar, Karoo-Ferrar large igneous provinces. The end of the Jurassic, however, has no clear boundary with the Cretaceous and i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Callovian
In the geologic timescale, the Callovian is an age and stage in the Middle Jurassic, lasting between 166.1 ± 4.0 Ma (million years ago) and 163.5 ± 4.0 Ma. It is the last stage of the Middle Jurassic, following the Bathonian and preceding the Oxfordian. Stratigraphic definitions The Callovian Stage was first described by French palaeontologist Alcide d'Orbigny in 1852. Its name derives from the latinized name for Kellaways Bridge, a small hamlet 3 km north-east of Chippenham, Wiltshire, England. The base of the Callovian is defined as the place in the stratigraphic column where the ammonite genus ''Kepplerites'' first appears, which is the base of the biozone of '' Macrocephalites herveyi''. A global reference profile (a GSSP) for the base had in 2009 not yet been assigned. The top of the Callovian (the base of the Oxfordian) is at the first appearance of ammonite species '' Brightia thuouxensis''. Subdivision The Callovian is often subdivided into three substages ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxfordian (stage)
The Oxfordian is, in the ICS' geologic timescale, the earliest age of the Late Jurassic Epoch, or the lowest stage of the Upper Jurassic Series. It spans the time between 163.5 ± 1.0 Ma and 157.3 ± 1.0 Ma (million years ago). The Oxfordian is preceded by the Callovian and is followed by the Kimmeridgian. Stratigraphic definitions The Oxfordian Stage was called "Clunch Clay and Shale" by William Smith (1815–1816); in 1818 W. Buckland described them under the unwieldy title "Oxford, Forest or Fen Clay". The term Oxfordian was introduced by Alcide d'Orbigny in 1844. The name is derived from the English city of Oxford, where the beds are well developed, but they crop out almost continuously from Dorset to the coast of Yorkshire, generally forming low, broad valleys. They are well exposed at Weymouth, Oxford, Bedford, Peterborough, and in the cliffs at Scarborough, Red Cliff and Gristhorpe Bay. Rocks of this age are found also in Uig and Skye. The base of the Oxfordian Stage ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Treatise On Invertebrate Paleontology
The ''Treatise on Invertebrate Paleontology'' (or ''TIP'') published by the Geological Society of America and the University of Kansas Press, is a definitive multi-authored work of some 50 volumes, written by more than 300 paleontologists, and covering every phylum, class, order, family, and genus of fossil and extant (still living) invertebrate animals. The prehistoric invertebrates are described as to their taxonomy, morphology, paleoecology, stratigraphic and paleogeographic range. However, taxa with no fossil record whatsoever have just a very brief listing. Publication of the decades-long ''Treatise on Invertebrate Paleontology'' is a work-in-progress; and therefore it is not yet complete: For example, there is no volume yet published regarding the post-Paleozoic era caenogastropods (a molluscan group including the whelk and Common periwinkle, periwinkle). Furthermore, every so often, previously published volumes of the ''Treatise'' are revised. Evolution of the proje ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jurassic Ammonites
The Jurassic ( ) is a geologic period and stratigraphic system that spanned from the end of the Triassic Period million years ago (Mya) to the beginning of the Cretaceous Period, approximately Mya. The Jurassic constitutes the middle period of the Mesozoic Era and is named after the Jura Mountains, where limestone strata from the period were first identified. The start of the Jurassic was marked by the major Triassic–Jurassic extinction event, associated with the eruption of the Central Atlantic Magmatic Province. The beginning of the Toarcian Stage started around 183 million years ago and is marked by an extinction event associated with widespread oceanic anoxia, ocean acidification, and elevated temperatures likely caused by the eruption of the Karoo-Ferrar large igneous provinces. The end of the Jurassic, however, has no clear boundary with the Cretaceous and is the only boundary between geological periods to remain formally undefined. By the beginning of the Jurassic, t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bathonian First Appearances
In the geologic timescale the Bathonian is an age and stage of the Middle Jurassic. It lasted from approximately 168.3 Ma to around 166.1 Ma (million years ago). The Bathonian Age succeeds the Bajocian Age and precedes the Callovian Age. Stratigraphic definitions The Bathonian Stage takes its name from Bath, a spa town in England built on Jurassic limestone (the Latinized form of the town name is ''Bathonium''). The name was introduced in scientific literature by Belgian geologist d'Omalius d'Halloy in 1843. The original type locality was located near Bath. The French palaeontologist Alcide d'Orbigny was in 1852 the first to define the exact length of the stage. The base of the Bathonian is at the first appearance of ammonite species '' Parkinsonia (Gonolkites) convergens'' in the stratigraphic column. The global reference profile for the base of the Bathonian (a GSSP) was ratified as Ravin du Bès, Bas-Auran area, Alpes de Haute Provence, France in 2009. The top of the Ba ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
