Corals are colonial marine invertebrates within the subphylum 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.
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 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 colonial. The founding polyp settles and starts to secrete calcium carbonate to protect its soft body. Solitary corals can be as much as 25 cm (10 in) 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 clones with a common skeleton, which may be up to several metres in diameter or height according to species.
Pillar coral is a hard coral found in the western Atlantic Ocean and the Caribbean Sea. It is the only species in the monotypic genus Dendrogyra. It is a digitate coral -that is, it resembles fingers or a cluster of cigars, growing up from the sea floor without any secondary branching. It is large and can grow on both flat and sloping surfaces at depths down to 20 m (65 ft). It is one of the few types of hard coral in which the polyps can commonly be seen feeding during the day.
Brain coral is a common name given to various corals in the families Mussidae and Merulinidae, so called due to their generally spheroid shape and grooved surface which resembles a brain. Each head of coral is formed by a colony of genetically identical polyps which secrete a hard skeleton of calcium carbonate; this makes them important coral reef builders like other stony corals in the order Scleractinia. Brain corals are found in shallow warm water coral reefs in all the world's oceans. They are part of the phylum Cnidaria, in a class called Anthozoa or "flower animals". The lifespan of the largest brain corals is 900 years. Colonies can grow as large as 1.8 m (6 ft) or more in height.
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.
The organ pipe coral is an alcyonarian octocoral native to the waters of the Indian Ocean and the central and western regions of the Pacific Ocean. It is the only known species of the genus Tubipora. This species is a soft coral but with a unique, hard skeleton of calcium carbonate that contains many organ pipe-like tubes. On each tube is a series of polyps which each have eight feather-like tentacles. These tentacles are usually extended during the day, but will swiftly withdraw with any sort of disturbance. The skeleton is a bright red color, but is typically obscured by numerous polyps. Because of this, living colonies are typically green, blue, or purple due to the color of the expanded polyps. Colonies are typically dome-shaped and can reach up to 3 meters across, while the individual polyps are typically less than 3 mm wide and a few mm long. They are close relatives to other soft coral and sea fans. This species is a popular aquarium coral due to its ease to maintain, as well as higher tolerance compared to most true corals. However, its popularity presents a problem: along with its potential as an aquarium coral, the species' coloration makes it a popular commodity for tourists, leading to a variety of threats to the population.
Alcyonacea are an order of sessile colonial cnidarians that are found throughout the oceans of the world, especially in the deep sea, polar waters, tropics and subtropics. Whilst not in a strict taxonomic sense, Alcyonacea are commonly known as soft corals. The term "soft coral" generally applies to organisms in the two orders Pennatulacea and Alcyonacea with their polyps embedded within a fleshy mass of coenenchymal tissue. Consequently, the term "gorgonian coral" is commonly handed to multiple species in the order Alcyonacea that produce a mineralized skeletal axis composed of calcite and the proteinaceous material gorgonin only and corresponds to only one of several families within the formally accepted taxon Gorgoniidae (Scleractinia). These can be found in order Malacalcyonacea (taxonomic synonyms of include : Alcyoniina, Holaxonia, Protoalcyonaria, Scleraxonia, and Stolonifera. They are sessile colonial cnidarians that are found throughout the oceans of the world, especially in the deep sea, polar waters, tropics and subtropics. Common names for subsets of this order are sea fans and sea whips; others are similar to the sea pens of related order Pennatulacea. Individual tiny polyps form colonies that are normally erect, flattened, branching, and reminiscent of a fan. Others may be whiplike, bushy, or even encrusting. A colony can be several feet high and across, but only a few inches thick. They may be brightly coloured, often purple, red, or yellow. Photosynthetic gorgonians can be successfully kept in captive aquaria.
Montipora is a genus of Scleractinian corals in the phylum Cnidaria. Members of the genus Montipora may exhibit many different growth morphologies. With eighty five known species, Montipora is the second most species rich coral genus after Acropora.
Blue coral is a species of colonial coral. It is the only octocoral known to produce a massive skeleton. This skeleton is formed of aragonite, similar to that of scleractinia. Individual polyps live in tubes within the skeleton and are connected by a thin layer of tissue over the outside of the skeleton.
Phyllodesmium colemani is a species of sea slug, an aeolid nudibranch, a marine gastropod mollusc in the family Facelinidae.
Lobophyllia, commonly called lobed brain coral or lobo coral, is a genus of large polyp stony corals. Members of this genus are sometimes found in reef aquariums.
Pavona is a genus of colonial stony corals in the family Agariciidae. These corals are found in shallow waters in the Indo-Pacific region.
Goniastrea is a genus of stony corals in the family Merulinidae. Species belonging to the genus Goniastrea forms massive colonies, usually spherical or elongate, with well developed paliform lobes. Polyps can be seen only at night.
Seriatopora is a genus of colonial stony corals in the family Pocilloporidae. They are commonly known as needle corals, birdsnest corals or finger corals. They are native to the Red Sea, the Indo-Pacific region and some parts of the Central Pacific Ocean.
Favites is a genus of stony corals in the family Merulinidae. Members of this genus are native to the Indo-Pacific region and their ranges extend from the Red Sea through the Indian Ocean and Western Pacific Ocean as far as Japan, the Line Islands and the Tuamotu Islands.
Merulina is a genus of stony corals in the family Merulinidae. Members of this genus are native to the Indo-Pacific region and their ranges extend from the Red Sea through the Indian Ocean as far as Japan and the southern central Pacific Ocean. Merulina ampliata is the type species.
Acropora hemprichii is a species of acroporid coral that was first described by Christian Gottfried Ehrenberg in 1834. It lives in reefs at depths of 3 to 15 m for between 13 and 24 years. The species is listed as vulnerable on the IUCN Red List, and has a decreasing population. It is common with a wide range, and is listed on Appendix II of CITES.
Acropora microclados is a species of acroporid coral that was first described by Christian Gottfried Ehrenberg in 1834. Found in marine, tropical shallow reefs on the upper slopes, it is found at depths of 5 to 20 m. It is listed as a vulnerable species on the IUCN Red List, and its population is decreasing. It is uncommon but found over a large area, including in five regions of Indonesia, and is classified under CITES Appendix II.
Orbicella is a genus of stony corals in the Merulinidae family. The Orbicella species complex comprises three sister species, namely Orbicella faveolata, Orbicella annularis and Orbicella franksi, all of which are shallow-water, zooxanthellate species and are native to the tropical western Atlantic Ocean, the Caribbean Sea and the Gulf of Mexico.
