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Macroneuropteris
''Macroneuropteris'' is a genus of Carboniferous seed plants in the order Medullosales. The genus is best known for the species ''Macroneuropteris scheuchzeri'', a medium-size tree that was common throughout the late Carboniferous Euramerica. Three similar species, ''M. macrophylla'', ''M. britannica'' and ''M. subauriculata'' are also included in the genus. Taxonomic history The most abundant species of this genus, ''Macroneuropteris scheuchzeri'', has had a long taxonomic history since it was first recognized in fossils found near Oxford, England by Edward Lhuyd in 1669. He referred to these leaves as ''Phyllites mineralis.'' It is illustrated and noted in Lhuyd's ''Lythophylacii Britannici Ichnographia'', an early manuscript on English fossils published in 1699 with the financial help of Isaac Newton. The species was further described in the ''Herbarium Diluvianum'' written in 1723 by the botanist Johann Jakob Scheuchzer. Nearly hundred years after Scheuchzer's death, the sp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Macroneuropteris Hair Structure
''Macroneuropteris'' is a genus of Carboniferous seed plants in the order Medullosales. The genus is best known for the species ''Macroneuropteris scheuchzeri'', a medium-size tree that was common throughout the late Carboniferous Euramerica. Three similar species, ''M. macrophylla'', ''M. britannica'' and ''M. subauriculata'' are also included in the genus. Taxonomic history The most abundant species of this genus, ''Macroneuropteris scheuchzeri'', has had a long taxonomic history since it was first recognized in fossils found near Oxford, England by Edward Lhuyd in 1669. He referred to these leaves as ''Phyllites mineralis.'' It is illustrated and noted in Lhuyd's ''Lythophylacii Britannici Ichnographia'', an early manuscript on English fossils published in 1699 with the financial help of Isaac Newton. The species was further described in the ''Herbarium Diluvianum'' written in 1723 by the botanist Johann Jakob Scheuchzer. Nearly hundred years after Scheuchzer's death, the sp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mazon Creek Fossil Beds
The Mazon Creek fossil beds are a conservation ' found near Morris, in Grundy County, Illinois. The fossils are preserved in ironstone concretions, formed approximately in the mid- Pennsylvanian epoch of the Carboniferous period. These concretions frequently preserve both hard and soft tissues of animal and plant materials, as well as many soft-bodied organisms that do not normally fossilize. The quality, quantity and diversity of fossils in the area, known since the mid-nineteenth century, make the Mazon Creek ' important to paleontologists, in attempting to reconstruct the paleoecology of the sites. The locality was declared a National Historic Landmark in 1997.. Geology The Mazon Creek fossils are found in the Upper Carboniferous Francis Creek Shale; the type locality is the Mazon River (or Mazon Creek), a tributary of the Illinois River near Morris, Grundy County, Illinois. The 25 to 30 meters of shale were formed approximately , during the Pennsylvanian period. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Medullosales
The Medullosales is an extinct order of pteridospermous seed plants characterised by large ovules with circular cross-section and a vascularised nucellus, complex pollen-organs, stems and rachides with a dissected stele, and frond-like leaves. Their nearest still-living relatives are the cycads. Most medullosales were small to medium-sized trees. The largest specimens were probably of genus ''Alethopteris'', whose fronds could be 7 metres long and the trees were perhaps up to 10 metres tall. Especially in Moscovian times, many medullosales were rather smaller, with fronds only about 2 metres long, and apparently growing in dense, mutually supporting stands. During Kasimovian and Gzhelian times there were also non-arboreal forms with smaller fronds (e.g. ''Odontopteris'') that were probably scrambling or possibly climbing plants. Ovules Ovules in different medullosalean species could vary from maybe 1 cm to over 10 cm long - the latter being the largest k ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mazon Creek Fossil Beds
The Mazon Creek fossil beds are a conservation ' found near Morris, in Grundy County, Illinois. The fossils are preserved in ironstone concretions, formed approximately in the mid- Pennsylvanian epoch of the Carboniferous period. These concretions frequently preserve both hard and soft tissues of animal and plant materials, as well as many soft-bodied organisms that do not normally fossilize. The quality, quantity and diversity of fossils in the area, known since the mid-nineteenth century, make the Mazon Creek ' important to paleontologists, in attempting to reconstruct the paleoecology of the sites. The locality was declared a National Historic Landmark in 1997.. Geology The Mazon Creek fossils are found in the Upper Carboniferous Francis Creek Shale; the type locality is the Mazon River (or Mazon Creek), a tributary of the Illinois River near Morris, Grundy County, Illinois. The 25 to 30 meters of shale were formed approximately , during the Pennsylvanian period. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arthropleura
''Arthropleura'' () is a genus of extinct millipede arthropods that lived in what is now North America and Europe around 345 to 290 million years ago, from the Viséan stage of the lower Carboniferous Period to the Sakmarian stage of the lower Permian Period. The species of the genus are the largest known land invertebrates of all time, and would have had few, if any, predators. Morphology File:20211224 Arthropleura armata anterior.png, Anterior morphology of ''A. armata'' File:20211225 Arthropleura leg associated structures.png, Leg and associated structures File:Millipede anterior anatomy.png, Modern millipede anatomy for comparison File:20211226 Largest Arthropleura.png, Size estimation of the largest specimen ''A. armata'' grew to be long. Tracks from ''Arthropleura'' up to wide have been found at Joggins, Nova Scotia. In 2021 a fossil was reported, probably a shed exoskeleton (exuviae) of an ''Arthropleura'' with an estimated width of , length of to and body mass of . ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cycads
Cycads are seed plants that typically have a stout and woody (ligneous) trunk with a crown of large, hard, stiff, evergreen and (usually) pinnate leaves. The species are dioecious, that is, individual plants of a species are either male or female. Cycads vary in size from having trunks only a few centimeters to several meters tall. They typically grow very slowly and live very long. Because of their superficial resemblance, they are sometimes mistaken for palms or ferns, but they are not closely related to either group. Cycads are gymnosperms (naked-seeded), meaning their unfertilized seeds are open to the air to be directly fertilized by pollination, as contrasted with angiosperms, which have enclosed seeds with more complex fertilization arrangements. Cycads have very specialized pollinators, usually a specific species of beetle. Both male and female cycads bear cones (strobili), somewhat similar to conifer cones. Cycads have been reported to fix nitrogen in associatio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thrips
Thrips ( order Thysanoptera) are minute (mostly long or less), slender insects with fringed wings and unique asymmetrical mouthparts. Different thrips species feed mostly on plants by puncturing and sucking up the contents, although a few are predators. Entomologists have described approximately 6,000 species. They fly only weakly and their feathery wings are unsuitable for conventional flight; instead, thrips exploit an unusual mechanism, clap and fling, to create lift using an unsteady circulation pattern with transient vortices near the wings. Many thrips species are pests of commercially important crops. A few species serve as vectors for over 20 viruses that cause plant disease, especially the Tospoviruses. Some species of thrips are beneficial as pollinators or as predators of other insects or mites. In the right conditions, such as in greenhouses, many species can exponentially increase in population size and form large swarms because of a lack of natural predators ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Supercontinent
In geology, a supercontinent is the assembly of most or all of Earth's continent, continental blocks or cratons to form a single large landmass. However, some geologists use a different definition, "a grouping of formerly dispersed continents", which leaves room for interpretation and is easier to apply to Precambrian times. To separate supercontinents from other groupings, a limit has been proposed in which a continent must include at least about 75% of the continental crust then in existence in order to qualify as a supercontinent. Supercontinents have assembled and dispersed multiple times in the geologic past (see table). According to modern definitions, a supercontinent does not exist today; the closest in existence to a supercontinent is the current Afro-Eurasian landmass, which covers approx. 57% of Earth's total land area. The last time the continental landmasses were near to one another was 336 to 175 million years ago as the supercontinent, Pangaea. The positions of con ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Asselian
In the geologic timescale, the Asselian is the earliest geochronologic age or lowermost chronostratigraphic stage of the Permian. It is a subdivision of the Cisuralian Epoch or Series. The Asselian lasted between and million years ago (Ma). It was preceded by the Gzhelian (the latest or uppermost subdivision in the Carboniferous) and followed by the Sakmarian. Stratigraphy The Asselian Stage was introduced into scientific literature in 1954, when the Russian stratigrapher V.E. Ruzhenchev split it from the Artinskian. At that moment the Artinskian still encompassed most of the lower Permian – its current definitions are more restricted. The Asselian is named after the Assel River in the southern Ural Mountains of Kazakhstan and Bashkortostan. The base of the Asselian Stage is at the same time the base of the Cisuralian Series and the Permian System. It is defined as the place in the stratigraphic record where fossils of the conodont ''Streptognathodus isolatus'' first appear ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bashkirian
The Bashkirian is in the ICS geologic timescale the lowest stage or oldest age of the Pennsylvanian. The Bashkirian age lasted from to Ma, is preceded by the Serpukhovian and is followed by the Moscovian. The Bashkirian overlaps with the upper part of the Namurian and lower part of the Westphalian stages from regional European stratigraphy. It also overlaps with the North American Morrowan and Atokan stages and the Chinese Luosuan and lower Huashibanian stages. Name and definition The Bashkirian was named after Bashkiria, the then Russian name of the republic of Bashkortostan in the southern Ural Mountains of Russia, home of the Bashkir people. The stage was introduced by Russian stratigrapher Sofia Semikhatova in 1934. The base of the Bashkirian is at the first appearance of conodont species ''Declinognathodus noduliferus''. The top of the stage (the base of the Moscovian) is at the first appearance of the conodonts ''Declinognathodus donetzianus'' or ''Idiognathoides ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Permian
The Permian ( ) is a geologic period and stratigraphic system which spans 47 million years from the end of the Carboniferous Period million years ago (Mya), to the beginning of the Triassic Period 251.9 Mya. It is the last period of the Paleozoic Era; the following Triassic Period belongs to the Mesozoic Era. The concept of the Permian was introduced in 1841 by geologist Sir Roderick Murchison, who named it after the region of Perm in Russia. The Permian witnessed the diversification of the two groups of amniotes, the synapsids and the sauropsids ( reptiles). The world at the time was dominated by the supercontinent Pangaea, which had formed due to the collision of Euramerica and Gondwana during the Carboniferous. Pangaea was surrounded by the superocean Panthalassa. The Carboniferous rainforest collapse left behind vast regions of desert within the continental interior. Amniotes, which could better cope with these drier conditions, rose to dominance in place of their am ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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