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Pavona Decussata
''Pavona decussata'', sometimes known as leaf coral, is a species of colonial stony coral in the family Agariciidae. It is found in shallow water in various reef habitats, particularly on gently sloping surfaces, in tropical parts of the western and central Indo-Pacific region. Description Colonies of ''Pavona decussata'' are submasive structures, usually with leafy appendages or branches. These leaves are between thick and have corallites on both sides. The corallites are between in diameter and are mostly scattered irregularly, but are sometimes in rows parallel to the margins of the leaves or of the radial ridges. The colour varies, but may be greenish or some shade of brown, orange or creamy yellow. Distribution and habitat ''Pavona decussata'' is native to the western and central Indo-Pacific region. Its range extends from East Africa and the Red Sea to Japan, the East China Sea, the Philippines, Papua New Guinea and eastern Australia. It is a fairly common species and o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Species
In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. Other ways of defining species include their karyotype, DNA sequence, morphology, behaviour or ecological niche. In addition, paleontologists use the concept of the chronospecies since fossil reproduction cannot be examined. The most recent rigorous estimate for the total number of species of eukaryotes is between 8 and 8.7 million. However, only about 14% of these had been described by 2011. All species (except viruses) are given a two-part name, a "binomial". The first part of a binomial is the genus to which the species belongs. The second part is called the specific name or the specific epithet (in botanical nomenclature, also sometimes i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 diffic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scleractinia
Scleractinia, also called stony corals or hard corals, are marine animals in the phylum Cnidaria that build themselves a hard skeleton. The individual animals are known as polyp (zoology), polyps and have a cylindrical body crowned by an oral disc in which a mouth is fringed with tentacles. Although some species are solitary, most are Colony (biology), colonial. The founding polyp settles and starts to secrete calcium carbonate to protect its soft body. Solitary corals can be as much as across but in colonial species the polyps are usually only a few millimetres in diameter. These polyps reproduce asexually by budding, but remain attached to each other, forming a multi-polyp colony of cloning, clones with a common skeleton, which may be up to several metres in diameter or height according to species. The shape and appearance of each coral colony depends not only on the species, but also on its location, depth, the amount of water movement and other factors. Many shallow-water co ... [...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 opini ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Agariciidae
The Agariciidae are a family of reef-building stony corals. This family includes cactus corals, plate corals, and lettuce corals. Members of the family include symbiotic algae called zooxanthellae in their tissues which help provide their energy requirements. Cactus, Elephant Skin, Plate, Lettuce Corals of the Family Agariciidae WetWebMedia.com. Retrieved 2011-12-18. Description Members of this family are , hermatypic (reef-building) corals. The corals form massive structures, often of a laminar or foliate form. The[...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Indo-Pacific
The Indo-Pacific is a vast biogeographic region of Earth. In a narrow sense, sometimes known as the Indo-West Pacific or Indo-Pacific Asia, it comprises the tropical waters of the Indian Ocean, the western and central Pacific Ocean, and the seas connecting the two in the general area of Indonesia. It does not include the temperate and polar regions of the Indian and Pacific oceans, nor the Tropical Eastern Pacific, along the Pacific coast of the Americas, which is also a distinct marine realm. The term is especially useful in marine biology, ichthyology, and similar fields, since many marine habitats are continuously connected from Madagascar to Japan and Oceania, and a number of species occur over that range, but are not found in the Atlantic Ocean. The region has an exceptionally high species richness, with the world's highest species richness being found in at its heart in the Coral Triangle, and a remarkable gradient of decreasing species richness radiating outward in al ... [...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 int ... [...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 Environment Pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vulnerable Species
A vulnerable species is a species which has been Conservation status, categorized by the International Union for Conservation of Nature as being threatened species, threatened with extinction unless the circumstances that are threatened species, threatening its survival and reproduction improve. Vulnerability is mainly caused by habitat loss or destruction of the species' home. Vulnerable habitat or species are monitored and can become increasingly threatened. Some species listed as "vulnerable" may be common in captivity (animal), captivity, an example being the military macaw. There are currently 5196 animals and 6789 plants classified as Vulnerable, compared with 1998 levels of 2815 and 3222, respectively. Practices such as cryoconservation of animal genetic resources have been enforced in efforts to conserve vulnerable breeds of livestock specifically. Criteria The International Union for Conservation of Nature uses several criteria to enter species in this category. A tax ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
International Union For Conservation Of Nature
The International Union for Conservation of Nature (IUCN; officially International Union for Conservation of Nature and Natural Resources) is an international organization working in the field of nature conservation and sustainable use of natural resources. It is involved in data gathering and analysis, research, field projects, advocacy, and education. IUCN's mission is to "influence, encourage and assist societies throughout the world to conserve nature and to ensure that any use of natural resources is equitable and ecologically sustainable". Over the past decades, IUCN has widened its focus beyond conservation ecology and now incorporates issues related to sustainable development in its projects. IUCN does not itself aim to mobilize the public in support of nature conservation. It tries to influence the actions of governments, business and other stakeholders by providing information and advice and through building partnerships. The organization is best known to the wider pu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Corals Described In 1846
Corals are marine invertebrates within the class Anthozoa of the phylum Cnidaria. They typically form compact colonies of many identical individual polyps. Coral species include the important reef builders that inhabit tropical oceans and secrete calcium carbonate to form a hard skeleton. A coral "group" is a colony of very many genetically identical polyps. Each polyp is a sac-like animal typically only a few millimeters in diameter and a few centimeters in height. A set of tentacles surround a central mouth opening. Each polyp excretes an exoskeleton near the base. Over many generations, the colony thus creates a skeleton characteristic of the species which can measure up to several meters in size. Individual colonies grow by asexual reproduction of polyps. Corals also breed sexually by spawning: polyps of the same species release gametes simultaneously overnight, often around a full moon. Fertilized eggs form planulae, a mobile early form of the coral polyp which, when matu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
