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Sagenopteris
''Sagenopteris'' is a genus of extinct seed ferns from the Triassic to late Early Cretaceous.''Sagenopteris'' at .org Description ''Sagenopteris'' has palmately arranged leaves with anastomosing venation. Different organs attributed to the same original plant can be reconstructed from co-occurrence at the same locality and from similarities in the stomatal apparatus and other anatomical peculiarities of fossilized cuticles. * '' Sagenopteris phillipsii'' may have been produced by the same plant as ''[...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sagenopteris Williamsii
''Sagenopteris williamsii'' is an extinct pteridosperm (seed fern) that is known from the late Jurassic and Early Cretaceous strata of the western interior of North America. It was first described as ''Chiropteris williamsii'' by J.S. Newberry in 1891, based on specimens from the Great Falls coal field in Montana.Newberry, J.S. 1891. The flora of the Great Falls Coal Field, Montana. American Journal of Science, 3rd series, vol. 41, p. 191-201 and plate 14. In 1956, it was referred to ''Sagenopteris'' by W.A. Bell based on additional specimens from western Canada.Bell, W.A. 1956. Lower Cretaceous floras of western Canada; Geological Survey of Canada, Memoir 285, p. 80-81 and plates 31, 33, 34, and 36. Description ''Sagenopteris williamsii'' had four or more palmately arranged, ovate to obovate leaves, each up to 10 cm long and 10 cm wide. They had a petiole, anastomosing venation, and a midvein that thinned toward the apex. Distribution and age Leaves of ''S. william ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sagenopteris Phillipsii
''Sagenopteris phillipsii'' are leaves of extinct species of seed ferns. Description ''Sagenopteris phillipsii'' has narrow, palmately arranged leaves with anastomosing venation Whole plant reconstructions Different organs attributed to the same original plant can be reconstructed from co-occurrence at the same locality and from similarities in the stomatal apparatus and other anatomical peculiarities of fossilized cuticles. *''Sagenopteris phillipsii'' may have been produced by the same plant as '' Caytonia nathorstii'' (ovulate organs) and '' Caytonanthus arberi'' (pollen organs). References Pteridospermatophyta Jurassic plants Fossil record of plants Jurassic first appearances Jurassic extinctions {{jurassic-plant-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sagenopteris Trapialensis
''Sagenopteris trapialensis'' are leaves of extinct species of seed fern from Chubut, Patagonia Argentina. At the moment, ''S. trapialensis'' is based on impression fossils found in the Early Jurassic Lonco Trapial Formation A lonko or lonco (from Mapudungun ''longko'', literally "head"), is a chief of several Mapuche communities. These were often ulmen, the wealthier men in the lof Lof (Spanish: ''levo'' and ''lov'') or caví (Spanish: ''cahuín''); formed the basic ... near Paso del Sapo, Chubut Province. Description ''Sagenopteris trapialensis'' comprises palmately arranged leaves with 4 ovate to obovate leaflets with anastomosing venation. The central leaflets are almost symmetrical, whereas the lateral ones are markedly asymmetrical. Various types of anastomoses are present, and dichotomies are simple. Leaves of various sizes and forms were found, ranging from less than 5 mm. and up to 80 mm long. References Pteridospermatophyta Jurassic plants ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jurassic Canada
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] |
Jurassic Mexico
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 Jura ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jurassic Plants
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 Jura ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jurassic United States
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] |
Valle Alto Formation
The Valle Alto Formation ( es, Formación Valle Alto, Jva) is a geological formation of the Central Ranges of the Colombian Andes. The formation is composed of shales, sandstones and conglomerates and dates to the Late Jurassic period. Ammonites and fossil flora have been found in the Valle Alto Formation. Etymology The formation was described and named in 1977 by González et al. after Hacienda Valle Alto, San Félix, Caldas.Moreno Sánchez et al., 2007Mojica, 1984, p.132 Lithologies The Valle Alto Formation is composed of shales, sandstones and conglomerates.Isagen, 2009, p.9 Stratigraphy, age and depositional environment The Valle Alto Formation, part of the Quebradagrande Complex, is not defined as a proper formation, rather as a collection of rocks of different facies origin segmented by tectonic forces of the Central Ranges. The Valle Alto Formation has been deposited as the result of marine incursions from the proto-Caribbean into Colombia, preceding the la ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Caytonia Nathorstii
''Caytonia nathorstii'' is an extinct species of seed ferns. Description ''Caytonia'' has berry like cupules with numerous small seeds arrayed along axes Whole plant reconstructions Different organs attributed to the same original plant can be reconstructed from co-occurrence at the same locality and from similarities in the stomatal apparatus and other anatomical peculiarities of fossilized cuticles. *''Caytonia nathorstii'' may have been produced by the same plant as '' Caytonanthus arberi'' (pollen organs) and '' Sagenopteris phillipsii'' (leaves). References Fossil record of plants Jurassic plants Pteridospermatophyta {{jurassic-plant-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Caytonanthus Arberi
''Caytonanthus'' is an extinct genus of seed ferns. Description ''Caytonanthus'' is the polliniferous organ-genus of the Caytoniales, and it is often found along '' Sagenopteris'' and ''Caytonia ''Caytonia'' is an extinct genus of seed ferns. Description ''Caytonia'' has berry like cupules with numerous small seeds arrayed along axes Whole plant reconstructions Different organs attributed to the same original plant can ...''. ''Caytonanthus'' remains have been found in Greenland, UK, Hungary Russia, Poland, India, Antarctica and Argentina. ''Caytonanthus'' has simple or multiple orders of branches arrayed along axes, each terminal branch bears one or many synangia, each composed by four, partially fused, pollen sacs. References Pteridospermatophyta Triassic plants Jurassic plants Cretaceous plants Prehistoric plant genera Triassic first appearances Cretaceous extinctions {{jurassic-plant-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fossil Record Of Plants
A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved in amber, hair, petrified wood and DNA remnants. The totality of fossils is known as the ''fossil record''. Paleontology is the study of fossils: their age, method of formation, and evolutionary significance. Specimens are usually considered to be fossils if they are over 10,000 years old. The oldest fossils are around 3.48 billion years old to 4.1 billion years old. Early edition, published online before print. The observation in the 19th century that certain fossils were associated with certain rock strata led to the recognition of a geological timescale and the relative ages of different fossils. The development of radiometric dating techniques in the early 20th century allowed scientists to quantitatively measure the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prehistoric Plants Of South America
Prehistory, also known as pre-literary history, is the period of human history between the use of the first stone tools by hominins 3.3 million years ago and the beginning of recorded history with the invention of writing systems. The use of symbols, marks, and images appears very early among humans, but the earliest known writing systems appeared 5000 years ago. It took thousands of years for writing systems to be widely adopted, with writing spreading to almost all cultures by the 19th century. The end of prehistory therefore came at very different times in different places, and the term is less often used in discussing societies where prehistory ended relatively recently. In the early Bronze Age, Sumer in Mesopotamia, the Indus Valley Civilisation, and ancient Egypt were the first civilizations to develop their own scripts and to keep historical records, with their neighbors following. Most other civilizations reached the end of prehistory during the following Iron Age. T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
