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Siderastrea Siderea
''Siderastrea siderea'', commonly known as massive starlet coral or round starlet coral, is a stony coral in the family Siderastreidae. It is found in shallow parts of the western Atlantic Ocean as solid boulder-shaped or domed structures. Description ''Siderastrea siderea'' is a colonial coral that forms low domes or boulder-shaped structures with a smooth dimpled surface as much as wide on the seabed. It can be encrusting when young. The corallites, the calcareous cup-shaped depressions in which the polyps sit, are about wide with about 50 or 60 little ridges called septa. The general colour is reddish brown. This species can be confused with the closely related lesser starlet coral ('' Siderastrea radians'') but that is usually smaller and has deeper, more angular corallites, each with 30 to 40 septa. Distribution and habitat ''Siderastrea siderea'' is found in the Caribbean Sea and the northern Gulf of Mexico and round the coasts of southern Florida, the Bahamas and Berm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Family (biology)
Family ( la, familia, plural ') is one of the eight major hierarchical taxonomic ranks in Linnaean taxonomy. It is classified between order and genus. A family may be divided into subfamilies, which are intermediate ranks between the ranks of family and genus. The official family names are Latin in origin; however, popular names are often used: for example, walnut trees and hickory trees belong to the family Juglandaceae, but that family is commonly referred to as the "walnut family". What belongs to a family—or if a described family should be recognized at all—are proposed and determined by practicing taxonomists. There are no hard rules for describing or recognizing a family, but in plants, they can be characterized on the basis of both vegetative and reproductive features of plant species. Taxonomists often take different positions about descriptions, and there may be no broad consensus across the scientific community for some time. The publishing of new data and opin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Siderastreidae
Siderastreidae is a family of reef building stony corals. Members of the family include symbiotic algae called Zooxanthellae in their tissues which help provide their energy requirements. Description Members of this family are colonial, hermatypic (reef-building) corals. The corals vary in form and include massive, thickly encrusting, columnar, and irregular forms. The corallites are linked by flowing septa that have granular margins and that are fused in the centre to give fan-shaped or star-shaped groupings. The corallites do not project from the surface of the coral and have ill-defined walls formed from thickened septa.Family Siderastreidae WetWebMedia.com. Retrieved 2011-12-18. Genera The World Register of Marine Species includes the following |
Colony (biology)
In biology, a colony is composed of two or more conspecific individuals living in close association with, or connected to, one another. This association is usually for mutual benefit such as stronger defense or the ability to attack bigger prey. Colonies can form in various shapes and ways depending on the organism involved. For instance, the bacterial colony is a cluster of identical cells (clones). These colonies often form and grow on the surface of (or within) a solid medium, usually derived from a single parent cell. Colonies, in the context of development, may be composed of two or more unitary (or solitary) organisms or be modular organisms. Unitary organisms have determinate development (set life stages) from zygote to adult form and individuals or groups of individuals (colonies) are visually distinct. Modular organisms have indeterminate growth forms (life stages not set) through repeated iteration of genetically identical modules (or individuals), and it can be diffi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Corallite
A corallite is the skeletal cup, formed by an individual stony coral polyp, in which the polyp sits and into which it can retract. The cup is composed of aragonite, a crystalline form of calcium carbonate, and is secreted by the polyp. Corallites vary in size, but in most colonial corals they are less than in diameter. The inner surface of the corallite is known as the calyx. The vertical blades inside the calyx are known as septa and in some species, these ridges continue outside the corallite wall as costae. Where there is no corallite wall, the blades are known as septocostae. The septa, costae and septocostae may have ornamentation in the form of teeth and may be thick, thin or variable in size. Sometimes there are paliform lobes, in the form of rods or blades, rising from the inner margins of the septa. These may form a neat circle called the paliform crown. The septa do not usually unite in the centre of the corallite, instead they form a columella, a tangled mass of i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polyp (zoology)
A polyp in zoology is one of two forms found in the phylum Cnidaria, the other being the medusa. Polyps are roughly cylindrical in shape and elongated at the axis of the vase-shaped body. In solitary polyps, the aboral (opposite to oral) end is attached to the substrate by means of a disc-like holdfast called a pedal disc, while in colonies of polyps it is connected to other polyps, either directly or indirectly. The oral end contains the mouth, and is surrounded by a circlet of tentacles. Classes In the class Anthozoa, comprising the sea anemones and corals, the individual is always a polyp; in the class Hydrozoa, however, the individual may be either a polyp or a medusa, with most species undergoing a life cycle with both a polyp stage and a medusa stage. In class Scyphozoa, the medusa stage is dominant, and the polyp stage may or may not be present, depending on the family. In those scyphozoans that have the larval planula metamorphose into a polyp, the po ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Septum (coral)
In corals, a septum (plural septa) is one of the radiating vertical plates lying within the corallite A corallite is the skeletal cup, formed by an individual stony coral polyp, in which the polyp sits and into which it can retract. The cup is composed of aragonite, a crystalline form of calcium carbonate, and is secreted by the polyp. Corall ... wall. Outside the corallite wall these plates are known as costae (singular costa). The septa may be thick, thin or vary in size. They may have teeth which range from needle-like to blade-like and are often characteristic of different genera. References {{reflist Cnidarian anatomy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Siderastrea Radians
''Siderastrea radians'', also known as the lesser starlet coral or the shallow-water starlet coral, is a stony coral in the family Siderastreidae. It is found in shallow parts of the western Atlantic Ocean as small, solid mounds or encrusting sheets. Description ''Siderastrea radians'' is either encrusting or grows in small, dimpled hummocks up to across but most colonies are much smaller than this. Occasionally it occurs as small calcareous pebbles that roll around in seagrass meadows or as loose flat discs in shallow rocky places. The corallites are not circular but are triangular or four-sided and deep, with 30 to 40 small ridges called septa. They have a dark interior that contrasts in colour with the pale surface of the coral which is greyish, greenish or light brown. The polyps are retracted back into these corallites during the day but emerge at night, extending their tentacles to feed. Each of these has a small knob of stinging cnidocytes at its tip. The lesser starlet ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IUCN Red List
The International Union for Conservation of Nature (IUCN) Red List of Threatened Species, also known as the IUCN Red List or Red Data Book, founded in 1964, is the world's most comprehensive inventory of the global conservation status of biological species. It uses a set of precise criteria to evaluate the extinction risk of thousands of species and subspecies. These criteria are relevant to all species and all regions of the world. With its strong scientific base, the IUCN Red List is recognized as the most authoritative guide to the status of biological diversity. A series of Regional Red Lists are produced by countries or organizations, which assess the risk of extinction to species within a political management unit. The aim of the IUCN Red List is to convey the urgency of conservation issues to the public and policy makers, as well as help the international community to reduce species extinction. According to IUCN the formally stated goals of the Red List are to provi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coral Bleaching
Coral bleaching is the process when corals become white due to various stressors, such as changes in temperature, light, or nutrients. Bleaching occurs when coral polyps expel the zooxanthellae ( dinoflagellates that are commonly referred to as algae) that live inside their tissue, causing the coral to turn white. The zooxanthellae are photosynthetic, and as the water temperature rises, they begin to produce reactive oxygen species. This is toxic to the coral, so the coral expels the zooxanthellae. Since the zooxanthellae produce the majority of coral colouration, the coral tissue becomes transparent, revealing the coral skeleton made of calcium carbonate. Most bleached corals appear bright white, but some are blue, yellow, or pink due to pigment proteins in the coral. The leading cause of coral bleaching is rising ocean temperature due to climate change. A temperature about 1 °C (or 2 °F) above average can cause bleaching. According to the United Nations Environmen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eutrophication
Eutrophication is the process by which an entire body of water, or parts of it, becomes progressively enriched with minerals and nutrients, particularly nitrogen and phosphorus. It has also been defined as "nutrient-induced increase in phytoplankton productivity". Water bodies with very low nutrient levels are termed oligotrophic and those with moderate nutrient levels are termed mesotrophic. Advanced eutrophication may also be referred to as dystrophic and hypertrophic conditions. Eutrophication can affect freshwater or salt water systems. In freshwater ecosystems it is almost always caused by excess phosphorus. In coastal waters on the other hand, the main contributing nutrient is more likely to be nitrogen, or nitrogen and phosphorus together. This depends on the location and other factors. When occurring naturally, eutrophication is a very slow process in which nutrients, especially phosphorus compounds and organic matter, accumulate in water bodies. These nutrients deri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
