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Armoricaphyton
''Armoricaphyton'' is an extinct monospecific genus of vascular land plants described from Early Devonian (late Pragian-earliest Emsian) outcrops of the Chalonnes Formation in western France. The plant consists of small, leafless, longitudinally-ribbed axes that branch pseudomonopodially. Pairs of fusiform-shaped, twisted sporangia preserved as adpressions were found in association with the axes and may belong to this species. Permineralized specimens reveal the oldest documented wood or secondary xylem of any known fossil plant. The water-conducting tissues or tracheids consisted of extinct P-type cell walls. This type of cell wall consisted of scalariform bordered pits and perforated sheets that covered the openings (apertures) of the pits. ''A. chateaupannense'' is anatomically similar in some respects to other members of the Euphyllophytina such as ''Psilophyton'' and ''Franhueberia''. ''Franhueberia gerriennei'' is also one of the earliest land plants described from the Ear ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Devonian
The Devonian ( ) is a geologic period and system of the Paleozoic era, spanning 60.3 million years from the end of the Silurian, million years ago (Mya), to the beginning of the Carboniferous, Mya. It is named after Devon, England, where rocks from this period were first studied. The first significant adaptive radiation of life on dry land occurred during the Devonian. Free-sporing vascular plants began to spread across dry land, forming extensive forests which covered the continents. By the middle of the Devonian, several groups of plants had evolved leaves and true roots, and by the end of the period the first seed-bearing plants appeared. The arthropod groups of myriapods, arachnids and hexapods also became well-established early in this period, after starting their expansion to land at least from the Ordovician period. Fish reached substantial diversity during this time, leading the Devonian to often be dubbed the Age of Fishes. The placoderms began dominat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Franhueberia
''Franhueberia'' is an extinct monospecific genus of vascular land plants described from Early Devonian (mid to late Emsian) outcrops of the Battery Point Formation along the south shore of Gaspé Bay, Quebec, Canada. Description The plant is preserved as a cellular permineralization within a single cobble and consists of a small axis with a centrarch protostele. The secondary tissues of the vascular cambium contain extinct P-type cell walls. This type of cell wall consisted of scalariform bordered pits and multiaperturate pit membranes. The secondary vascular tissues in ''Franhueberia gerriennei'' represent one of the oldest examples of secondary growth. Wood or secondary xylem with P-type cell walls have also been observed in the slightly older (late Pragian-earliest Emsian) '' Armoricaphyton chateaupannense'' from western France and in an unnamed basal euphyllophyte from late Emsian outcrops of the Campbellton Formation in New Brunswick, Canada. Taxonomy ''Franhueberia g ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Early Devonian Land Plants
The list of Early Devonian (419.2 ± 2.8 to 393.3 ± 2.5 million years ago) land plants includes currently known vascular and potentially vascular plants, along with some possibly non-vascular plants, that have been described from global Early Devonian fossil 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 ... assemblages. List of land plants References {{reflist * * * * See also * Devonian Devonian plants ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Early Devonian
The Early Devonian is the first of three epochs comprising the Devonian period, corresponding to the Lower Devonian series. It lasted from and began with the Lochkovian Stage , which was followed by the Pragian from and then by the Emsian, which lasted until the Middle Devonian began, . During this time, the first ammonoids appeared, descending from bactritoid nautiloids. Ammonoids during this time period were simple and differed little from their nautiloid counterparts. These ammonoids belong to the order Agoniatitida, which in later epochs evolved to new ammonoid orders, for example Goniatitida and Clymeniida. This class of cephalopod molluscs would dominate the marine fauna until the beginning of the Mesozoic The Mesozoic Era ( ), also called the Age of Reptiles, the Age of Conifers, and colloquially as the Age of the Dinosaurs is the second-to-last era of Earth's geological history, lasting from about , comprising the Triassic, Jurassic and Cretace ... Era. Refe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chalonnes Formation , in the Maine-et-Loire ''département''
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Chalonnes is part of the name of two ''communes'' in France: * Chalonnes-sous-le-Lude, in the Maine-et-Loire ''département'' * Chalonnes-sur-Loire Chalonnes-sur-Loire is a commune in the Maine-et-Loire department in western France. It is located on the left bank of the river Loire in the Loire Valley UNESCO World Heritage Site area. Geography The town is in the heart of the Anjou, a hist ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sporangia
A sporangium (; from Late Latin, ) is an enclosure in which spores are formed. It can be composed of a single cell or can be multicellular. Virtually all plants, fungi, and many other lineages form sporangia at some point in their life cycle. Sporangia can produce spores by mitosis, but in nearly all land plants and many fungi, sporangia are the site of meiosis and produce genetically distinct haploid spores. Fungi In some phyla of fungi, the sporangium plays a role in asexual reproduction, and may play an indirect role in sexual reproduction. The sporangium forms on the sporangiophore and contains haploid nuclei and cytoplasm. Spores are formed in the sporangiophore by encasing each haploid nucleus and cytoplasm in a tough outer membrane. During asexual reproduction, these spores are dispersed via wind and germinate into haploid hyphae. Although sexual reproduction in fungi varies between phyla, for some fungi the sporangium plays an indirect role in sexual reproductio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Permineralized
Permineralization is a process of fossilization of bones and tissues in which mineral deposits form internal casts of organisms. Carried by water, these minerals fill the spaces within organic tissue. Because of the nature of the casts, permineralization is particularly useful in studies of the internal structures of organisms, usually of plants. Process Permineralization, a type of fossilization, involves deposits of minerals within the cells of organisms. Water from the ground, lakes, or oceans seeps into the pores of organic tissue and forms a crystal cast with deposited minerals. Crystals begin to form in the porous cell walls. This process continues on the inner surface of the walls until the central cavity of the cell, the lumen, is completely filled. The cell walls themselves remain intact surrounding the crystals. Silicification In silicification, the weathering of rocks releases silicate minerals and the silica makes its way into a body of still water. Eventually, the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wood
Wood is a porous and fibrous structural tissue found in the stems and roots of trees and other woody plants. It is an organic materiala natural composite of cellulose fibers that are strong in tension and embedded in a matrix of lignin that resists compression. Wood is sometimes defined as only the secondary xylem in the stems of trees, or it is defined more broadly to include the same type of tissue elsewhere such as in the roots of trees or shrubs. In a living tree it performs a support function, enabling woody plants to grow large or to stand up by themselves. It also conveys water and nutrients between the leaves, other growing tissues, and the roots. Wood may also refer to other plant materials with comparable properties, and to material engineered from wood, or woodchips or fiber. Wood has been used for thousands of years for fuel, as a construction material, for making tools and weapons, furniture and paper. More recently it emerged as a feedstock for the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Secondary Xylem
Xylem is one of the two types of transport tissue in vascular plants, the other being phloem. The basic function of xylem is to transport water from roots to stems and leaves, but it also transports nutrients. The word ''xylem'' is derived from the Ancient Greek word (''xylon''), meaning "wood"; the best-known xylem tissue is wood, though it is found throughout a plant. The term was introduced by Carl Nägeli in 1858. Structure The most distinctive xylem cells are the long tracheary elements that transport water. Tracheids and vessel elements are distinguished by their shape; vessel elements are shorter, and are connected together into long tubes that are called ''vessels''. Xylem also contains two other type of cells: parenchyma and fibers. Xylem can be found: * in vascular bundles, present in non-woody plants and non-woody parts of woody plants * in secondary xylem, laid down by a meristem called the vascular cambium in woody plants * as part of a stelar arrangement not ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tracheids
A tracheid is a long and tapered lignified cell in the xylem of vascular plants. It is a type of conductive cell called a tracheary element. Angiosperms use another type of tracheary element, called vessel elements, to transport water through the xylem. The main functions of tracheid cells are to transport water and inorganic salts, and to provide structural support for trees. There are often pits on the cell walls of tracheids, which allows for water flow between cells. Tracheids are dead at functional maturity and do not have a protoplast. The wood ( softwood) of gymnosperms such as pines and other conifers is mainly composed of tracheids. Tracheids are also the main conductive cells in the primary xylem of ferns. The tracheid was first named after the German botanist Carl Gustav Sanio in 1863, from the German ''Tracheide''. Evolution Tracheids were the main conductive cells found in early vascular plants. In the first 140-150 million years of vascular plant evolution ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Euphyllophytina
The euphyllophytes are a clade of plants within the tracheophytes (the vascular plants). The group may be treated as an unranked clade, a division Division or divider may refer to: Mathematics *Division (mathematics), the inverse of multiplication *Division algorithm, a method for computing the result of mathematical division Military *Division (military), a formation typically consisting ... under the name Euphyllophyta or a subdivision under the name Euphyllophytina. The euphyllophytes are characterized by the possession of true leaves ("megaphylls"), and comprise one of two major lineages of extant vascular plants. As shown in the cladogram below, the euphyllophytes have a sister relationship to the lycopodiophytes or lycopsids. Unlike the lycopodiophytes, which consist of relatively few presently living or extant taxa, the euphyllophytes comprise the vast majority of vascular plant lineages that have evolved since both groups shared a common ancestor more than 400 mill ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Psilophyton
''Psilophyton'' is a genus (biology), genus of extinct vascular plants. Described in 1859, it was one of the first fossil plants to be found which was of Devonian age (about ). Specimens have been found in northern Maine, USA; Gaspé Bay, Quebec and New Brunswick, Canada; the Czech Republic; and Yunnan, China. Plants lacked leaves or true roots; spore-forming organs or Sporangium, sporangia were borne on the ends of branched clusters. It is significantly more complex than some other plants of comparable age (e.g. ''Rhynia'') and is thought to be part of the group from within which the modern ferns and seed plants evolved. Description Almost all the species of ''Psilophyton'' have been found in rocks of Emsian age (around ). One exception is ''P. krauselii'', from the Czech Republic, which is younger, being from the upper part of the Middle Devonian (around ). ''Psilophyton dawsonii'' is the best-known species. Compressed and mineralized specimens have been found in sever ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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