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Leptosporangiate Ferns
The Polypodiidae, commonly called leptosporangiate ferns, formerly Leptosporangiatae, are one of four subclasses of ferns, the largest of these being the largest group of living ferns, including some 11,000 species worldwide. The group has also been treated as the class Pteridopsida or Polypodiopsida, although other classifications assign them a different rank. Older names for the group include Filicidae and Filicales, although at least the "water ferns" (now the Salviniales) were then treated separately. The leptosporangiate ferns are one of the four major groups of ferns, with the other three being the eusporangiate ferns comprising the marattioid ferns (Marattiidae, Marattiaceae), the horsetails (Equisetiidae, Equisetaceae), and whisk ferns and moonworts. There are approximately 8465 species of living leptosporangiate ferns, compared with about 2070 for all other ferns, totalling 10535 species of ferns. Almost a third of leptosporangiate fern species are epiphytes. These ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Early Carboniferous
Early may refer to: Places in the United States * Early, Iowa, a city * Early, Texas, a city * Early Branch, a stream in Missouri * Early County, Georgia * Fort Early, Georgia, an early 19th century fort Music * Early B, stage name of Jamaican dancehall and reggae deejay Earlando Arrington Neil (1957–1994) * Early James, stage name of American singer-songwriter Fredrick Mullis Jr. (born 1993) * Early (Scritti Politti album), ''Early'' (Scritti Politti album), 2005 * Early (A Certain Ratio album), ''Early'' (A Certain Ratio album), 2002 * Early Records, a record label Other uses * Early (name), a list of people and fictional characters with the given name or surname * Early effect, an effect in transistor physics * Early, a synonym for ''hotter'' in Stellar classification#"Early" and "late" nomenclature, stellar classification See also * * The Earlies, a 21st century band * Earley (other) * Earlie, a given name {{disambiguation, geo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Equisetaceae
Equisetaceae, also known as the horsetail family, is a family of ferns and the only surviving family of the order Equisetales, with one surviving genus, ''Equisetum'', comprising about twenty species. Evolution and systematics Equisetaceae is the only surviving family of the Equisetales, a group with many fossils of large tree-like plants that possessed ribbed stems similar to modern horsetails. '' Pseudobornia'' is the oldest known relative of ''Equisetum''; it grew in the late Devonian, about 375 million years ago and is assigned to its own order. All living horsetails are placed in the genus ''Equisetum''. But there are some fossil species that are not assignable to the modern genus. '' Equisetites'' is a " wastebin taxon" uniting all sorts of large horsetails from the Mesozoic; it is almost certainly paraphyletic and would probably warrant being subsumed in ''Equisetum''. But while some of the species placed there are likely to be ancestral to the modern horsetails, there ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heterosporous
Heterospory is the production of spores of two different sizes and sexes by the sporophytes of land plants. The smaller of these, the microspore, is male and the larger megaspore is female. Heterospory evolved during the Devonian period from isospory independently in several plant groups: the clubmosses, the ferns including the arborescent horsetails, and progymnosperms. This occurred as part of the process of evolution of the timing of sex differentiation.Sussex, I.M. (1966) The origin and development of heterospory in vascular plants. Chapter 9 in ''Trends in Plant morphogenesis'', ed. by E.G. Cutter, Longmans. Four extant groups of plants are heterosporous; Selaginella, Isoetes, Salviniales and seed plants. Origin of heterospory Heterospory evolved due to natural selection that favoured an increase in propagule size compared with the smaller spores of homosporous plants. Heterosporous plants, similar to anisosporic plants, produce two different sized spores in separa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Molecular Phylogenetic
Molecular phylogenetics () is the branch of phylogeny that analyzes genetic, hereditary molecular differences, predominantly in DNA sequences, to gain information on an organism's evolutionary relationships. From these analyses, it is possible to determine the processes by which diversity among species has been achieved. The result of a molecular phylogenetic analysis is expressed in a phylogenetic tree. Molecular phylogenetics is one aspect of molecular systematics, a broader term that also includes the use of molecular data in taxonomy and biogeography. Molecular phylogenetics and molecular evolution correlate. Molecular evolution is the process of selective changes (mutations) at a molecular level (genes, proteins, etc.) throughout various branches in the tree of life (evolution). Molecular phylogenetics makes inferences of the evolutionary relationships that arise due to molecular evolution and results in the construction of a phylogenetic tree. History The theoretical fra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polypodium
''Polypodium'' is a genus of ferns in the family Polypodiaceae, subfamily Polypodioideae, according to the Pteridophyte Phylogeny Group classification of 2016 (PPG I). The genus is widely distributed throughout the world, with the highest species diversity in the tropics. The name is derived from Ancient Greek ''poly'' ("many") + ''podion'' ("little foot"), on account of the foot-like appearance of the rhizome and its branches. They are commonly called polypodies or rockcap ferns, but for many species unique vernacular names exist. They are terrestrial or epiphytic ferns, with a creeping, densely hairy or scaly rhizome bearing fronds at intervals along its length. The species differ in size and general appearance and in the character of the fronds, which are evergreen, persisting for 1–2 years, pinnate or pinnatifid (rarely simple entire), and from 10 to 80 cm or more long. The sori or groups of spore-cases (sporangia) are borne on the back of the frond; they are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Homosporous
In biology, a spore is a unit of sexual (in fungi) or asexual reproduction that may be adapted for dispersal and for survival, often for extended periods of time, in unfavourable conditions. Spores form part of the life cycles of many plants, algae, fungi and protozoa. They were thought to have appeared as early as the mid-late Ordovician period as an adaptation of early land plants. Bacterial spores are not part of a sexual cycle, but are resistant structures used for survival under unfavourable conditions. Myxozoan spores release amoeboid infectious germs ("amoebulae") into their hosts for parasitic infection, but also reproduce within the hosts through the pairing of two nuclei within the plasmodium, which develops from the amoebula. In plants, spores are usually haploid and unicellular and are produced by meiosis in the sporangium of a diploid sporophyte. In some rare cases, a diploid spore is also produced in some algae, or fungi. Under favourable conditions, the spore ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Christian Luerssen
Christian Luerssen (6 May 1843, Bremen – 28 June 1916) was a German botanist. He was an authority in the field of pteridology. In 1872, at Leipzig, he graduated as a university teacher of botany, and was later appointed professor of botany at the Forest Academy at Neustadt-Eberswalde (1884). From 1888, he served as a professor at the University of Königsberg. After his death, a portion of his botanical collection (including European pteridophytes) was donated by Otto Bjurling to the Swedish Museum of Natural History. Luerssen was the taxonomic authority of the family Sciadopityaceae (1877). He has a number of plant species named after him, such as ''Koeleria luerssenii'' (grass species) and ''Cassia luerssenii'' (family Fabaceae). Written works * ''Filices Graeffeanae. Beitrag zur kenntniss der farnflora der Viti-, Samoa-, Tonga- und Ellice's inseln'', 1871 - Contribution to the knowledge of ferns of Viti Levu, Samoa, Tonga and the Ellice Islands. * ''Grundzüge der Bo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Karl Ritter Von Goebel
Karl Immanuel Eberhard Ritter von Goebel FRS FRSE (8 March 1855, Billigheim, Baden Germany, Baden – 9 October 1932, Munich) was a German botanist. His main fields of study were comparative functional anatomy, morphology (biology), morphology, and the developmental physiology of plants under the influence of both phylogenetic and extrinsic factors. Life Starting in 1873, Goebel studied theology and philosophy, as well as botany with Wilhelm Hofmeister, at the University of Tuebingen. In 1876 he moved to Strasbourg, where he worked with Anton de Bary, and from which he graduated in 1877 with his Ph.D. In 1878, Goebel became assistant to Julius von Sachs, and in 1880 a lecturer at the University of Würzburg. In 1881 he became first assistant to August Schenk of the University of Leipzig, then an associate professor at Strasbourg, and 1882 associate professor at the University of Rostock, where in 1884 he founded the botanical garden and a botanical institute. From 1887–1891 he ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Annulus (botany)
An annulus in botany is for ferns an arc or a ring of specialized cells on the sporangium. These cells are arranged in a single row, and are associated with the release or dispersal of spores. In mosses it is a ring of cells around the tip of the sporangium. In flowers it is a ring of hairs within the flower tube. Ferns In leptosporangiate ferns, the annulus located on the outer rim of the sporangium and serves in spore dispersal. It consists typically of a ring or belt of dead water-filled cells with differentially thickened cell walls that stretches about two-thirds around each sporangium in leptosporangiate ferns. The thinner walls on the outside allow water to evaporate quickly under dry conditions. This Dehiscence (botany), dehiscence causes the cells to shrink and a contraction and straightening of the annulus ring, eventually rupturing the sporangial wall by ripping apart thin-walled lip cells on the opposite side of the sporangium. The annulus slowly straightens and conti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sorus
A sorus (: sori) is a cluster of sporangia (structures producing and containing spores) in ferns and fungi. A coenosorus (: coenosori) is a compound sorus composed of multiple, fused sori. Etymology This Neo-Latin word is from Ancient Greek σωρός (''sōrós'' 'stack, pile, heap'). Structure In lichens and other fungi, the sorus is surrounded by an external layer. In some red algae, it may take the form of depression into the thallus. In ferns, the sori form a yellowish or brownish mass on the edge or underside of a fertile frond. In some species, they are protected during development by a scale or film of tissue called the indusium (: indusia), which forms an umbrella-like cover. Life cycle significance Sori occur on the sporophyte generation, the sporangia within producing haploid meiospores. As the sporangia mature, the indusium shrivels so that spore release is unimpeded. The sporangia then burst and release the spores. As an aid to identification The shape, arrang ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sporangium
A sporangium (from Late Latin, ; : sporangia) is an enclosure in which spores are formed. It can be composed of a unicellular organism, single cell or can be multicellular organism, multicellular. Virtually all plants, fungus, fungi, and many other groups form sporangia at some point in their biological life cycle, life cycle. Sporangia can produce spores by mitosis, but in land plants and many fungi, sporangia produce genetically distinct haploid spores by meiosis. It's outdated name, sporange, is one of the few perfect rhymes for Orange (colour), orange. 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 Ploidy, haploid Cell nucleus, 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 g ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
