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Charales
Charales is an order of freshwater green algae in the division Charophyta, class Charophyceae, commonly known as stoneworts. Depending on the treatment of the genus '' Nitellopsis'', living (extant) species are placed into either one family ( Characeae) or two (Characeae and Feistiellaceae). Further families are used for fossil members of the order. Linnaeus established the genus '' Chara'' in 1753. Taxonomy The higher level classification of green algae was unsettled . AlgaeBase places Charales within the class Charophyceae and its circumscription of the division Charophyta. Families The number of families and their division into genera varies. , AlgaeBase accepts two families containing some extant species and four families containing only fossil species: * Characeae S.F.Gray * Feistiellaceae Schudack *† Aclistocharaceae X.G.Zhou (may be included in Characeae) *† Atopocharaceae R.E.Peck (may be included in Clavatoraceae) *† Clavatoraceae Pia *† Porocharaceae Gr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Charophyta
Charophyta () is a paraphyletic group of freshwater green algae, called charophytes (), sometimes treated as a division, yet also as a superdivision. The terrestrial plants, the Embryophyta emerged deep within Charophyta, possibly from terrestrial unicellular charophytes, with the class Zygnematophyceae as a sister group. With the Embryophyta now cladistically placed in the Charophyta, it is a synonym of Streptophyta. The sister group of the charophytes are the Chlorophyta. In some charophyte groups, such as the Zygnematophyceae or conjugating green algae, flagella are absent and sexual reproduction does not involve free-swimming flagellate sperm. Flagellate sperm, however, are found in stoneworts ( Charales) and Coleochaetales, orders of parenchymatous charophytes that are the closest relatives of the land plants, where flagellate sperm are also present in all except the conifers and flowering plants. Fossil stoneworts of early Devonian age that are similar to those of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Charophyceae
Charophyceae is a class of charophyte green algae. AlgaeBase places it in division Charophyta. Extant (living) species are placed in a single order Charales, commonly known as "stoneworts" and "brittleworts". Fossil members of the class may be placed in separate orders, e.g. Sycidiales and Trochiliscales. Charophyceae is basal in the Phragmoplastophyta clade which contains the embryophytes (land plants).Hoek, C. van den, Mann, D. G. & Jahns, H. M. 1995''Algae: An Introduction to Phycology'' Cambridge University Press, Cambridge. McCourt, R. M., Chapman, R. L., Buchheim, M. & Mishler, B. D“Green Plants” Accessed 13 December 2007 In 2018, the first nuclear genome sequence from a species belonging to the Charophyceae was published: that of '' Chara braunii''. Description The thallus is erect with regular nodes and internodes. At each node there is a whorl of branches. The whole plant is calcified and ''Equisetum ''Equisetum'' (; horsetail) is the only living genus in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chara (alga)
''Chara'' is a genus of charophyte green algae in the family Characeae. They are multicellular and superficially resemble land plants because of stem-like and leaf-like structures. They are found in freshwater, particularly in limestone areas throughout the northern temperate zone, where they grow submerged, attached to the muddy bottom. They prefer less oxygenated and hard water and are not found in waters where mosquito larvae are present. They are covered with calcium carbonate (CaCO3) deposits and are commonly known as stoneworts. Cyanobacteria have been found growing as epiphytes on the surfaces of ''Chara'', where they may be involved in fixing nitrogen, which is important to plant nutrition. Structure The branching system of ''Chara'' species is complex with branches derived from apical cells which cut off segments at the base to form nodal and internodal cells alternately.Round, F.E. 1965.''The Biology of the algae.'' Ernest Arnold. The main axes bear whorls of bra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Characeae
Characeae is a family of freshwater green algae in the order Charales, commonly known as stoneworts. They are also known as brittleworts or skunkweed, from the fragility of their lime-encrusted stems, and from the foul odor these produce when stepped on. In some treatments, the Characeae includes all the living (extant) species of Charales; this circumscription is followed here. In other treatments, the genus '' Nitellopsis'', which has both extant and extinct species, is placed in a separate family, Feistiellaceae. Description Living members of the Characeae ''sensu lato'' grow in freshwater and brackish environments worldwide, and have large, macroscopic thalli growing up to 120 cm long, they are branched, multicellular, and use chlorophyll to photosynthesize. Their only diploid stage in the life cycle is the unicellular oospore. They may be called ''stoneworts'', because the plants can become encrusted in lime (calcium carbonate) after some time. The "stem" is actual ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Feistiellaceae
Feistiellaceae is a family of freshwater green algae in the order Charales. Genera , AlgaeBase and Fossilworks accepted three genera: *†'' Amblyochara'' Grambast – 6 species *†'' Feistiella'' Schudack – 8 species *'' Nitellopsis'' Hy – 24 species With this circumscription, the family as a whole is not extinct, since ''Nitellopsis'' contains living (extant) species, including the widely dispersed ''Nitellopsis obtusa''. Other sources place ''Nitellopsis'' in the family Characeae Characeae is a family of freshwater green algae in the order Charales, commonly known as stoneworts. They are also known as brittleworts or skunkweed, from the fragility of their lime-encrusted stems, and from the foul odor these produce when ste ..., leaving Feistiellaceae with only extinct genera. References Charophyta Chlorophyta families {{Green alga-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chara Globularis
''Chara globularis'' is a species of charophyte green algae The green algae (: green alga) are a group of chlorophyll-containing autotrophic eukaryotes consisting of the phylum Prasinodermophyta and its unnamed sister group that contains the Chlorophyta and Charophyta/ Streptophyta. The land plants ... in the family Characeae. Native to Europe, but widespread among the world, it inhabits fresh and brackish-water environments. The ''Chara globularis'' originally documented was identified as the short-end segment(SH) type, with a black fossa wall containing a granulate, papillate, or fine pusticular pattern. An elongate-end(EL) type was previously thought to belong to this same species, but upon re-examination was determined to be phylogenetically separate from the ''Chara globularis,'' indicating that it was a different species and, thus, being reclassified as the ''Chara leptospira''. References Charophyta Freshwater algae Plants described in 1799 {{Green a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paleogene
The Paleogene Period ( ; also spelled Palaeogene or Palæogene) is a geologic period and system that spans 43 million years from the end of the Cretaceous Period Ma (million years ago) to the beginning of the Neogene Period Ma. It is the first period of the Cenozoic Era, the tenth period of the Phanerozoic and is divided into the Paleocene, Eocene, and Oligocene epochs. The earlier term Tertiary Period was used to define the time now covered by the Paleogene Period and subsequent Neogene Period; despite no longer being recognized as a formal stratigraphic term, "Tertiary" still sometimes remains in informal use. Paleogene is often abbreviated "Pg", although the United States Geological Survey uses the abbreviation "" for the Paleogene on the Survey's geologic maps. Much of the world's modern vertebrate diversity originated in a rapid surge of diversification in the early Paleogene, as survivors of the Cretaceous–Paleogene extinction event took advantage of empty ecolo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neontology
Neontology is a part of biology that, in contrast to paleontology, studies and deals with living (or, more generally, '' recent'') organisms. It is the study of extant taxa (singular: extant taxon): taxa (such as species, genera and families) with members still alive, as opposed to (all) being extinct. For example: * The Indian elephant (''Elephas maximus'') is an extant species, and the woolly mammoth (''Mammuthus primigenius'') is an extinct species. * The moose (''Alces alces'') is an extant species, and the Irish elk (''Megaloceros giganteus'') is an extinct species. * In the group of molluscs known as the cephalopods, there were approximately 600 extant species and 7,500 extinct species. A taxon can be classified as extinct if it is broadly agreed or certified that no members of the group are still alive. Conversely, an extinct taxon can be reclassified as extant if there are new discoveries of living species (" Lazarus species"), or if previously known extant species ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paleontology
Paleontology, also spelled as palaeontology or palæontology, is the scientific study of the life of the past, mainly but not exclusively through the study of fossils. Paleontologists use fossils as a means to classify organisms, measure geologic time, and assess the interactions between prehistoric organisms and their natural environment. While paleontological observations are known from at least the 6th century BC, the foundation of paleontology as a science dates back to the work of Georges Cuvier in 1796. Cuvier demonstrated evidence for the concept of extinction and how life of the past was not necessarily the same as that of the present. The field developed rapidly over the course of the following decades, and the French word ''paléontologie'' was introduced for the study in 1822, which was derived from the Ancient Greek word for "ancient" and words describing relatedness and a field of study. Further advances in the field accompanied the work of Charles Darwin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
