Scleractinia in the context of "Fragmentation (reproduction)"

A carbonate platform is a sedimentary body which possesses topographic relief, and is composed of autochthonic calcareous deposits. Platform growth is mediated by sessile organisms whose skeletons build up the reef or by organisms (usually microbes) which induce carbonate precipitation through their metabolism. Therefore, carbonate platforms can not grow up everywhere: they are not present in places where limiting factors to the life of reef-building organisms exist. Such limiting factors are, among others: light, water temperature, transparency and pH. For example, carbonate sedimentation along the Atlantic South American coasts takes place everywhere but at the mouth of the Amazon River, because of the intense turbidity of the water there. Spectacular examples of present-day carbonate platforms are the Bahama Banks under which the platform is roughly 8 km thick, the Yucatan Peninsula which is up to 2 km thick, the Florida platform, the platform on which the Great Barrier Reef is growing, and the Maldive atolls. All these carbonate platforms and their associated reefs are confined to tropical latitudes. Today's reefs are built mainly by scleractinian corals, but in the distant past other organisms, like archaeocyatha (during the Cambrian) or extinct cnidaria (tabulata and rugosa) were important reef builders.

Seriatopora hystrix is a species of colonial stony coral in the family Pocilloporidae. It forms a branching clump and is commonly known as thin birdsnest coral. It grows in shallow water on fore-reef slopes or in sheltered lagoons, the type locality being the Fiji Islands. It is native to East Africa, the Red Sea and the western Indo-Pacific region. It is a common species and the International Union for Conservation of Nature has assessed its conservation status as being a "Vulnerable species".

Anthozoa is one of the three subphyla of Cnidaria, along with Medusozoa and Endocnidozoa. It includes sessile marine invertebrates and invertebrates of brackish water, such as sea anemones, stony corals, soft corals and sea pens. Almost all adult anthozoans are attached to the seabed, while their larvae can disperse as plankton. The basic unit of the adult is the polyp, an individual animal consisting of a cylindrical column topped by a disc with a central mouth surrounded by tentacles. Sea anemones are mostly solitary, but the majority of corals are colonial, being formed by the budding of new polyps from an original, founding individual. Colonies of stony corals are strengthened by mainly aragonite and other materials, and can take various massive, plate-like, bushy or leafy forms.

Members of Anthozoa possess cnidocytes, a feature shared among other cnidarians such as the jellyfish, box jellies and parasitic Myxozoa and Polypodiozoa. The two classes of Anthozoa are class Hexacorallia, with members that have six-fold symmetry such as stony corals, sea anemones, tube anemones and zoanthids, and class Octocorallia, with members that have eight-fold symmetry, such as soft corals, gorgonians (sea pens, sea fans and sea whips), and sea pansies. Some additional species are also included as incertae sedis until their exact taxonomic position can be ascertained.

Acropora is a genus of small polyp stony coral in the phylum Cnidaria. Some of its species are known as table coral, elkhorn coral, and staghorn coral. Over 149 species are described. Acropora species are some of the major reef corals responsible for building the immense calcium carbonate substructure that supports the thin living skin of a reef.

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 3 mm (0.12 in) 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 intertwined septa, or a dome-shaped or pillar-like projection. In the living coral, the lower part of the polyp is in intimate contact with the corallite, and has radial mesenteries between the septa which increase the surface area of the body cavity and aid digestion. The septa, palliform lobes and costae can often be seen through the coenosarc, the layer of living tissue that covers the coenosteum, the part of the skeleton between the corallites.

In colonial species, when the corallites each have a surrounding wall, the colony is said to be plocoid. When the walls are tall and tubular, the colony is phaceloid, and when several polyps share a common wall, the colony is cerioid. Sometimes the polyps are in valleys on the surface of solid corals, they are then known as meandroid. Branching corals have two forms of corallites, axial and radial. The axial corallites tend to be shallow and are found near the tips of the branches, while the radial corallites are on the sides of the branches. Corallites can be rounded or polygonal and may be inclined (tilted obliquely to one side).

The Pocilloporidae are a family of stony corals in the order Scleractinia occurring in the Pacific and Indian Oceans.

The crown-of-thorns starfish (frequently abbreviated to COTS), Acanthaster planci, is a large starfish that preys upon hard, or stony, coral polyps (Scleractinia). The crown-of-thorns starfish receives its name from venomous thornlike spines that cover its upper surface, resembling the biblical crown of thorns. It is one of the largest starfish in the world.

A. planci has a very wide Indo-Pacific distribution. It is perhaps most common around Australia, but can occur at tropical and subtropical latitudes from the Red Sea and the East African coast across the Indian Ocean, and across the Pacific Ocean to the west coast of Central America. It occurs where coral reefs or hard coral communities occur in the region.

The staghorn coral (Acropora cervicornis) is a branching, stony coral, within the Order Scleractinia. It is characterized by thick, upright branches which can grow in excess of 2 meters (6.5 ft) in height and resemble the antlers of a stag, hence the name, Staghorn. It grows within various areas of a reef but is most commonly found within shallow fore and back reefs, as well as patch reefs, where water depths rarely exceed 20 meters (65 ft). Staghorn corals can exhibit very fast growth, adding up to 5 cm (~2 in) in new skeleton for every 1 cm of existing skeleton each year, making them one of the fastest growing fringe coral species in the Western Atlantic. Due to this fast growth, Acropora cervicornis, serve as one of the most important reef building corals, functioning as marine nurseries for juvenile fish, buffer zones for erosion and storms, and center points of biodiversity in the Western Atlantic.

Up until the late 1970s, much of the fore reef zones within the Atlantic around the coasts of Southern Florida and the Caribbean Islands were covered with vast, dense colonies of Staghorn coral consisting largely of single-species stands; however, a combination of white-band disease and various anthropogenic factors have reduced this coral coverage by over 95% in some areas.

The Carnian pluvial episode (CPE), often called the Carnian pluvial event, was a period of major change in global climate that coincided with significant changes in Earth's biota both in the sea and on land. It occurred during the latter part of the Carnian Stage, the first subdivision of the Late Triassic Epoch, and lasted for perhaps 1–2 million years (around 234–232 million years ago). Volcanic activity off the coast of North America led to global warming and increased rainfall on land, alongside a reduction of carbonate platforms in the oceans. Pluvial means "of or relating to rain; characterized by much rain, rainy."

The CPE corresponds to a significant episode in the evolution and diversification of many taxa that are important today. The earliest dinosaurs (which include the ancestors of birds), lepidosaurs (the ancestors of modern-day lizards, snakes, and the tuatara) and potentially mammaliaforms (ancestors of mammals) all diversified during the event. In the marine realm it saw the first appearance among the microplankton of coccoliths and dinoflagellates, with the latter linked to the rapid diversification of scleractinian corals through the establishment of symbiotic zooxanthellae within them. The CPE also saw the extinction of many aquatic invertebrate species, especially among ammonoids, bryozoans, and crinoids.