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 end is attached to the substrate by means of a disc-like holdfast called the 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.
Corals are marine invertebrates within the class Anthozoa of the phylum Cnidaria. They typically live in 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.
Anthozoa is a class of marine invertebrates which includes the sea anemones, stony corals and soft corals. Adult anthozoans are almost all attached to the seabed, while their larvae can disperse as part of the plankton. The basic unit of the adult is the polyp; this consists 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 are strengthened by calcium carbonate and other materials and take various massive, plate-like, bushy or leafy forms.
The Atlantic sea nettle, also known as the East Coast sea nettle or US Atlantic sea nettle, is a species of jellyfish that inhabits the Atlantic coast of the United States. Historically it was confused with several Chrysaora species, resulting in incorrect reports of C. quinquecirrha from other parts of the Atlantic and other oceans. Most recently, C. chesapeakei of estuaries on the Atlantic coast of the United States, as well as the Gulf of Mexico, was only fully recognized as separate from C. quinquecirrha in 2017. It is smaller than the Pacific sea nettle, and has more variable coloration, but is typically pale, pinkish or yellowish, often with radiating more deeply colored stripes on the exumbrella, especially near the margin.
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.
Mussidae is a family of stony coral in the order Scleractinia. Following a taxonomic revision in 2012, the family is now restricted to species found in the Atlantic Ocean, with Pacific species transferred to the new family Lobophylliidae. Many species are referred to as brain coral because their generally spheroid form and grooved surface resembles the convolutions of a brain.
Aiptasia is a genus of a symbiotic cnidarian belonging to the class Anthozoa. Aiptasia is a widely distributed genus of temperate and tropical sea anemones of benthic lifestyle typically found living on mangrove roots and hard substrates. These anemones, as well as many other cnidarian species, often contain symbiotic dinoflagellate unicellular algae of the genus Symbiodinium living inside nutritive cells. The symbionts provide food mainly in the form of lipids and sugars produced from photosynthesis to the host while the hosts provides inorganic nutrients and a constant and protective environment to the algae. Species of Aiptasia are relatively weedy anemones able to withstand a relatively wide range of salinities and other water quality conditions. In the case of A. pallida and A. pulchella, their hardiness coupled with their ability to reproduce very quickly and out-compete other species in culture gives these anemones the status of pest from the perspective of coral reef aquarium hobbyists. These very characteristics make them easy to grow in the laboratory and thus they are extensively used as model organisms for scientific study. In this respect, Aiptasia have contributed a significant amount of knowledge regarding cnidarian biology, especially human understanding of cnidarian-algal symbioses, a biological phenomenon crucial to the survival of corals and coral reef ecosystems. The dependence of coral reefs on the health of the symbiosis is dramatically illustrated by the devastating effects experienced by corals due to the loss of algal symbionts in response to environmental stress, a phenomenon known as coral bleaching.
Sea anemones are the marine, predatory animals of the order Actiniaria. They are named after the anemone, a terrestrial flowering plant, because of the colourful appearance of many. Sea anemones are classified in the phylum Cnidaria, class Anthozoa, subclass Hexacorallia. As cnidarians, sea anemones are related to corals, jellyfish, tube-dwelling anemones, and Hydra. Unlike jellyfish, sea anemones do not have a medusa stage in their life cycle.
Porites astreoides, commonly known as mustard hill coral or yellow porites, is a colonial species of stony coral in the family Poritidae.
Tubastraea, also known as sun coral or sun polyps, is a genus of coral in the phylum Cnidaria. It is a cup coral in the family Dendrophylliidae.
Pocillopora is a genus of stony corals in the family Pocilloporidae occurring in the Pacific and Indian Oceans. They are commonly called cauliflower corals and brush corals.
Balanophyllia bonaespei is a species of solitary cup coral, a stony coral in the family Dendrophylliidae. It is an azooxanthellate species that does not contain symbiotic dinoflagellates in its tissues as most corals do.
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.
Cynarina lacrymalis is a species of stony coral in the family Lobophylliidae. It is variously known as the flat cup coral, solitary cup coral, button coral, doughnut coral, or cat's eye coral. It is found in the western Indo-Pacific Ocean and is sometimes kept in reef aquaria.
Balanophyllia europea, called also scarlet coral or pig-tooth coral, is a small species of stony coral in the family Dendrophylliidae.
Leptopsammia pruvoti, the sunset cup coral, is a solitary stony coral in the family Dendrophylliidae. It is an azooxanthellate species, meaning its tissues do not contain the symbiotic unicellular algae (zooxanthellae) of the genus Symbiodinium, as do most corals. It is native to the Mediterranean Sea. The species was described by Henri de Lacaze-Duthiers in 1897 and named to honor the French marine biologist Georges Pruvot.
Astroides is a genus of stony cup corals in the family Dendrophylliidae. It is monotypic and the only species is Astroides calycularis, which is endemic to the western Mediterranean Sea. The species was first described in 1766 by the German naturalist Peter Simon Pallas.
Schizocyathus is a monotypic genus of stony corals in the family Schizocyathidae, the only species being Schizocyathus fissilis. It is a deep water, azooxanthellate coral.
Cycloseris curvata is a species of disc coral in the family Fungiidae. Cyclosteris curvata is a mostly solitary free living scleractinian disc coral found in the indo-pacific region. They grow on soft substrates and are known to tolerate turbid waters. Like other anthozoan corals they lack a medusa stage characteristic of other cnidarians. They have been observed as both green and brown in color in the field.
Flabellum curvatum is a species of marine, cold water coral in the family Flabellidae. It is an azooxanthellate coral, that is to say without symbiotic zooxanthellae. The species is native to deep waters around Antarctica.
