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Sagenopteris
''Sagenopteris'' is a genus of extinct seed ferns from the Triassic to late Early Cretaceous.''Sagenopteris'' at Fossilworks.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. * '''' may have been produced by the same plant as '' |
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. williamsii'' ... [...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 ''Caytonia nathorstii'' is an extinct species of seed fern A seed is an Plant embryogenesis, embryonic plant enclosed in a testa (botany), protective outer covering, along with a food reserve. The formation of the seed is a part of the pro ...'' (ovulate organs) and '' Caytonanthus arberi'' (pollen organs). References Pteridospermatophyta Jurassic plants Fossil record of plants Jurassic first appearances Jurassic extinctio ... [...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 near Paso del Sapo, Chubut Province Chubut ( es, Provincia del Chubut, ; cy, Talaith Chubut) is a province in southern Argentina, situated between the 42nd parallel south (the border with Río Negro Province), the 46th parallel south (bordering Santa Cruz Province), the Ande .... 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 F ... [...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 Jurassic, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
