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Posidoniaceae
''Posidonia'' is a genus of flowering plants. It contains nine species of marine plants ("seagrass"), found in the seas of the Mediterranean and around the south coast of Australia. The APG system (1998) and APG II system (2003) accept this genus as constituting the sole genus in the family Posidoniaceae, which it places in the order Alismatales, in the clade monocots. The AP-Website concludes that the three families Cymodoceaceae, Posidoniaceae and Ruppiaceae form a monophyletic group. Earlier systems classified this genus in the family Potamogetonaceae or in the family Posidoniaceae but belonging to order Zosterales. ''Posidonia oceanica'' has nitrogen fixation capabilities via symbiosis and other species may as well. Species This is a list of species that are contained by the genus: *''Posidonia angustifolia'' Cambridge and Kuo *''Posidonia australis'' Hook.f. South coast of Australia. *''Posidonia coriacea'' Cambridge and Kuo *''Posidonia denhartogii'' Kuo and Cambridge ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Posidonia Denhartogii
''Posidonia'' is a genus of flowering plants. It contains nine species of marine plants ("seagrass"), found in the seas of the Mediterranean and around the south coast of Australia. The APG system (1998) and APG II system (2003) accept this genus as constituting the sole genus in the family Posidoniaceae, which it places in the order Alismatales, in the clade monocots. The AP-Website concludes that the three families Cymodoceaceae, Posidoniaceae and Ruppiaceae form a monophyletic group. Earlier systems classified this genus in the family Potamogetonaceae or in the family Posidoniaceae but belonging to order Zosterales. ''Posidonia oceanica'' has nitrogen fixation capabilities via symbiosis and other species may as well. Species This is a list of species that are contained by the genus: *'' Posidonia angustifolia'' Cambridge and Kuo *''Posidonia australis'' Hook.f. South coast of Australia. *''Posidonia coriacea'' Cambridge and Kuo *'' Posidonia denhartogii'' Kuo and Cambri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Posidonia Angustifolia
''Posidonia'' is a genus of flowering plants. It contains nine species of marine plants ("seagrass"), found in the seas of the Mediterranean and around the south coast of Australia. The APG system (1998) and APG II system (2003) accept this genus as constituting the sole genus in the family Posidoniaceae, which it places in the order Alismatales, in the clade monocots. The AP-Website concludes that the three families Cymodoceaceae, Posidoniaceae and Ruppiaceae form a monophyletic group. Earlier systems classified this genus in the family Potamogetonaceae or in the family Posidoniaceae but belonging to order Zosterales. ''Posidonia oceanica'' has nitrogen fixation capabilities via symbiosis and other species may as well. Species This is a list of species that are contained by the genus: *'' Posidonia angustifolia'' Cambridge and Kuo *''Posidonia australis'' Hook.f. South coast of Australia. *''Posidonia coriacea'' Cambridge and Kuo *''Posidonia denhartogii'' Kuo and Cambrid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Posidonia Kirkmanii
''Posidonia'' is a genus of flowering plants. It contains nine species of marine plants ("seagrass"), found in the seas of the Mediterranean and around the south coast of Australia. The APG system (1998) and APG II system (2003) accept this genus as constituting the sole genus in the family Posidoniaceae, which it places in the order Alismatales, in the clade monocots. The AP-Website concludes that the three families Cymodoceaceae, Posidoniaceae and Ruppiaceae form a monophyletic group. Earlier systems classified this genus in the family Potamogetonaceae or in the family Posidoniaceae but belonging to order Zosterales. ''Posidonia oceanica'' has nitrogen fixation capabilities via symbiosis and other species may as well. Species This is a list of species that are contained by the genus: *'' Posidonia angustifolia'' Cambridge and Kuo *''Posidonia australis'' Hook.f. South coast of Australia. *''Posidonia coriacea'' Cambridge and Kuo *'' Posidonia denhartogii'' Kuo and Cambri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Seagrass
Seagrasses are the only flowering plants which grow in marine environments. There are about 60 species of fully marine seagrasses which belong to four families (Posidoniaceae, Zosteraceae, Hydrocharitaceae and Cymodoceaceae), all in the order Alismatales (in the clade of monocotyledons). Seagrasses evolved from terrestrial plants which recolonised the ocean 70 to 100 million years ago. The name ''seagrass'' stems from the many species with long and narrow leaves, which grow by rhizome extension and often spread across large "meadows" resembling grassland; many species superficially resemble terrestrial grasses of the family Poaceae. Like all autotrophic plants, seagrasses photosynthesize, in the submerged photic zone, and most occur in shallow and sheltered coastal waters anchored in sand or mud bottoms. Most species undergo submarine pollination and complete their life cycle underwater. While it was previously believed this pollination was carried out without pollinators ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Posidonia Oceanica
''Posidonia oceanica'', commonly known as Neptune grass or Mediterranean tapeweed, is a seagrass species that is endemic to the Mediterranean Sea. It forms large underwater meadows that are an important part of the ecosystem. The fruit is free floating and known in Italy as "the olive of the sea" (''l'oliva di mare''). Balls of fibrous material from its foliage, known as ''egagropili'' or ''Neptune balls'', wash up to nearby shorelines. The Posidonia has a very high carbon absorption capacity, being able to soak up 15 times more carbon dioxide every year than a similar sized piece of the Amazon rainforest. Morphology Posidonia oceanica has roots (which mainly serve to anchor the plant to the substrate), rhizome and tapeform leaves. The rhizomes, up to 1 cm thick, grow both horizontally (plagiotropic rhizomes), and vertically (orthotropic rhizomes). The former, thanks to the presence at the bottom of lignited roots up to 15 cm long, anchor the plant to the substrate. The latte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ruppiaceae
''Ruppia'', also known as the widgeonweeds, ditch grasses or widgeon grass, is the only extant genus in the family Ruppiaceae, with eight known species. These are aquatic plants widespread over much of the world. The genus name honours Heinrich Bernhard Rupp, a German botanist (1688-1719). They are widespread outside of frigid zones and the tropics. Description The leaf is simple and not rhizomatous. They can be annual (commonly) or perennial (rarely); stem growth is conspicuously sympodial, but sometimes is not. These species are adapted to be in brackish water (and salt marshes). The leaves are small or medium-sized. Their disposition can be alternate, opposite, or whorled (usually alternate except when subtending an inflorescence). Even, lamina keep entire and are setaceous or linear. The leaf just shows one vein without cross-venules. Stomata are not present. The mesophyll leaks calcium oxalate crystals. The minor leaf veins do not present phloem transfer cells and leaks ves ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cymodoceaceae
Cymodoceaceae is a family of flowering plants, sometimes known as the "manatee-grass family", which includes only marine species. The 2016 APG IV does recognize Cymodoceaceae and places it in the order Alismatales, in the clade monocots. The family includes five genera, totaling 17 species occurring in tropical seas and oceans (so-called seagrasses). According to thAP-Websiteit is doubtful if the family Ruppiaceae is distinct enough to be kept apart. The inclusion of the sole genus ''Ruppia'' in Ruppiaceae in Cymodoceaceae is being considered. The plants in the three families Cymodoceaceae, Posidoniaceae and Ruppiaceae form a monophyletic group. Its fossil record shows that Cymodoceaceae was established in its current Indo-West Pacific distribution by the early Eocene and perhaps even during the late Paleocene. Fossils of ''Thalassodendron auriculalopris'' den Hartog and ''Cymodocea floridana'' den Hartog (both extant) were also found in west-central Florida and date back to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alismatales
The Alismatales (alismatids) are an order of flowering plants including about 4,500 species. Plants assigned to this order are mostly tropical or aquatic. Some grow in fresh water, some in marine habitats. Description The Alismatales comprise herbaceous flowering plants of often aquatic and marshy habitats, and the only monocots known to have green embryos other than the Amaryllidaceae. They also include the only marine angiosperms growing completely submerged, the seagrasses. The flowers are usually arranged in inflorescences, and the mature seeds lack endosperm. Both marine and freshwater forms include those with staminate flowers that detach from the parent plant and float to the surface. There they can pollinate carpellate flowers floating on the surface via long pedicels. In others, pollination occurs underwater, where pollen may form elongated strands, increasing chance of success. Most aquatic species have a totally submerged juvenile phase, and flowers are either ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Potamogetonaceae
The Potamogetonaceae, commonly referred to as the pondweed family, is an aquatic family of monocotyledonous flowering plants. The roughly 110 known species are divided over six genera. The largest genus in the family by far is ''Potamogeton'', which contains about 100 species. The family has a subcosmopolitan distribution, and is considered to be one of the most important angiosperm groups in the aquatic environment because of its use as food and habitat for aquatic animals.Haynes, R. R. 1975. A revision of North American ''Potamogeton'' subsection Pusilli (Potamogetonaceae). Rhodora 76: 564--64 Taxonomy The Potamogetonaceae are currently placed in the early diverging monocot order Alismatales by the Angiosperm Phylogeny Group. Their concept of the family includes the plants sometimes treated in the separate family Zannichelliaceae, but excludes the genus '' Ruppia''. So circumscribed, the family currently consists of six genera: ''Althenia'', ''Groenlandia'', ''Lepilaena'', '' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Posidonia Robertsoniae
''Posidonia robertsoniae'' is one of the seagrasses of Western Australia, submerged flowering plants that occurs in the southern coastal waters. Description A species of ''Posidonia'', submerged flowering plants found in Mediterranean climates. A perennial rhizomatous herb that appears as stands in marine habitat. This species is found at depths from 0.5 to 20 metres on white sands, in coastal waters that may be sheltered or subject to intense wave action. The habit of ''Posidonia robertsoniae'' is as a clumping stand, it is rhizomatous plant that puts out shoots with one or two leaves. The leaf blades are 2.5 to 4 millimetres wide, and 1.5 metres long. They are slightly leathery and uneven on the upper surfaces. Between 6 and 9 veins appear on each leaf. The flowering period is primarily during the months of August and September. Distribution ''Posidonia robertsoniae'' is recorded at coasts of Southwest Australia, from Warnbro Sound to Israelite Bay. Taxonomy This species ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Posidonia Australis
''Posidonia australis'', also known as fibre-ball weed or ribbon weed, is a species of seagrass that occurs in the southern waters of Australia. It forms large meadows important to environmental conservation. Balls of decomposing detritus from the foliage are found along nearby shore-lines. In 2022, a single stand in Shark Bay was reported by scientists to be the largest plant in the world. Description ''Posidonia australis'' is a flowering plant occurring in dense meadows, or along channels, in white sand. It is found at depths from . Subsurface rhizomes and roots provide stability in the sands it occupies. Erect rhizomes and leaves reduce the accumulation of silt. The leaves are ribbon-like and wide. They are bright green, perhaps becoming browned with age. The terminus of the leaf is rounded or absent through damage. They are arranged in groups with older leaves on the outside, longer and differing in form from the younger leaves they surround. The species is monoecious. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
APG System
The APG system (Angiosperm Phylogeny Group system) of plant classification is the first version of a modern, mostly molecular-based, system of plant taxonomy. Published in 1998 by the Angiosperm Phylogeny Group, it was replaced by the improved APG II in 2003, APG III system in 2009 and APG IV system in 2016. History The original APG system is unusual in being based, not on total evidence, but on the cladistic analysis of the DNA sequences of three genes, two chloroplast genes and one gene coding for ribosomes. Although based on molecular evidence only, its constituent groups prove to be supported by other evidence as well, for example pollen morphology supports the split between the eudicots and the rest of the former dicotyledons. The system is rather controversial in its decisions at the family level, splitting a number of long-established families and submerging some other families. It also is unusual in not using botanical names above the level of order, that is, an orde ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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