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.
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.
Porites astreoides, commonly known as mustard hill coral or yellow porites, is a colonial species of stony coral in the family Poritidae.
The Pocilloporidae are a family of stony corals in the order Scleractinia occurring in the Pacific and Indian Oceans.
Porites lobata, known by the common name lobe coral, is a species of stony coral in the family Poritidae. It is found growing on coral reefs in tropical parts of the Indian and Pacific Oceans.
Favia fragrum is a species of colonial stony coral in the family Mussidae. It is commonly known as the golfball coral and is found in tropical waters on either side of the Atlantic Ocean.
Eusmilia is a genus of stony coral in the family Meandrinidae. It is a monotypic genus represented by the species Eusmilia fastigiata, commonly known as the smooth flower coral. It is found on reefs in the Caribbean Sea.
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.
Stylophora pistillata, commonly known as hood coral or smooth cauliflower coral, is a species of stony coral in the family Pocilloporidae. It is native to the Indo-Pacific region and is commonly used in scientific investigations.
Pseudodiploria clivosa, the knobby brain coral, is a colonial species of stony coral in the family Mussidae. It occurs in shallow water in the West Atlantic Ocean and Caribbean Sea.
Plexaurella nutans, the giant slit-pore sea rod, is a tall species of soft coral in the family Plexauridae. It is a relatively uncommon species and is found in shallow seas in the Caribbean region.
Pocillopora verrucosa, commonly known as cauliflower coral, rasp coral, or knob-horned coral, is a species of stony coral in the family Pocilloporidae. It is native to tropical and subtropical parts of the Indian and Pacific Oceans.
Astrangia poculata, the northern star coral or northern cup coral, is a species of non-reefbuilding stony coral in the family Rhizangiidae. It is native to shallow water in the western Atlantic Ocean and the Caribbean Sea. It is also found on the western coast of Africa. The International Union for Conservation of Nature lists this coral as being of "least concern". Astrangia poculata is an emerging model organism for corals because it harbors a facultative photosymbiosis, is a calcifying coral, and has a large geographic range. Research on this emerging model system is showcased annually by the Astrangia Research Working Group, collaboratively hosted by Roger Williams University, Boston University, and Southern Connecticut State University
Astrangia solitaria, the dwarf cup coral or southern cup coral, is a species of stony coral in the family Rhizangiidae. It is native to shallow water in the western Atlantic Ocean and the Caribbean Sea.
Carijoa riisei, the snowflake coral or branched pipe coral, is a species of soft coral in the family Clavulariidae. It was originally thought to have been native to the tropical western Atlantic Ocean and subsequently spread to other areas of the world such as Hawaii and the greater tropical Pacific, where it is regarded as an invasive species. The notion that it is native to the tropical western Atlantic was perpetuated from the fact that the type specimen, described by Duchassaing & Michelotti in 1860, was collected from the US Virgin Islands. It has subsequently been shown through molecular evidence that it is more likely that the species is in fact native to the Indo-Pacific and subsequently spread to the western tropical Atlantic most likely as a hull fouling species prior to its original description.
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 Red Sea. 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 of "least concern".
Euphylliidae are known as a family of polyped stony corals under the order Scleractinia.
Manicina areolata, commonly known as rose coral, is a colonial species of stony coral. It occurs in shallow water in the West Atlantic Ocean and Caribbean Sea, sometimes as small solid heads and sometimes as unattached cone-shaped forms.
Stylophora madagascarensis is a species of stony coral in the family Pocilloporidae. It is native to the tropical western Indian Ocean where it is confined to the coasts of Madagascar, growing in shallow water.
