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.
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.
Lybia edmondsoni is a species of small crab in the family Xanthidae and is endemic to the Hawaiian Islands. Like other members of the genus Lybia, it is commonly known as the pom-pom crab or boxer crab because of its habit of carrying a sea anemone around in each of its claws, these resembling pom-poms or boxing gloves. Its Hawaiian name is kūmimi pua, meaning "inedible flower crab". In ancient times, this animal was used by men claiming to be sorcerers.
Anthopleura michaelseni, commonly known as the long-tentacled anemone or crevice anemone, is a species of sea anemone in the family Actiniidae. It is native to very shallow water round the coasts of southern Africa between Lüderitz and Durban.
Peachia cylindrica is a large species of sea anemone in the family Haloclavidae. It is normally found burrowed into soft substrates, the only visible part of the animal being the oral disc and tentacles which usually lie flat on the sand. It is the type species of the genus Peachia.
Triactis is a genus of sea anemone in the family Aliciidae. It is monotypic, having only one species – Triactis producta. This is found in shallow waters in the Indo-Pacific where it lives on the seabed, rocks and corals. It derives much of its energy needs from the symbiotic algae it contains. It also forms a mutualistic relationship with small Lybia crabs.
Cerianthus lloydii is a species of tube-dwelling sea anemone in the family Cerianthidae. It is sometimes called the lesser cylinder anemone and is found in shallow seas around the coasts of north west Europe.
The burrowing anemone is a species of tube-dwelling anemone in the family Cerianthidae.
Heteractis malu, also known as the malu anemone, delicate sea anemone or white sand anemone, is a species of sea anemone in the family Stichodactylidae.
Condylactis aurantiaca, commonly known as the golden anemone, is a species of sea anemone in the family Actiniidae. This species always remains largely buried in sand or sediment, attached to the substrate, with only the oral disc and tentacles visible.
Phlyctenanthus australis, commonly known as red anemone and southern anemone, is a species of sea anemone in the family Actiniidae. It grows to a maximum size of 10 cm in diameter. The column is red-brown in colour with blue vesicles covering it. The tentacles are reddish-brown and short, and number up to around 100. This species is found in south Australia, New South Wales, down to Tasmania. This species lives on exposed reefs at depths of between 1 and 35 metres.
Anthopleura ballii, commonly known as the red speckled anemone, is a species of sea anemone in the family Actiniidae. It is found in shallow water in the northeastern Atlantic Ocean.
Cerianthus membranaceus, the cylinder anemone or coloured tube anemone, is a species of large, tube-dwelling anemone in the family Cerianthidae. It is native to the Mediterranean Sea and adjoining parts of the northeastern Atlantic Ocean.
Ceriantheopsis americana is a species of tube-dwelling anemone in the family Cerianthidae. It is a burrowing species and lives in deep sand or muddy sand in a long slender tube that it creates.
Diadumene leucolena, commonly known as the white anemone or ghost anemone, is a species of sea anemone in the family Diadumenidae. It is an inconspicuous species found in the intertidal and subtidal areas of the northeastern Atlantic Ocean, the Caribbean Sea and the northern Pacific Ocean. Diadumene, "diadem-bearer", referring to the crown of tentacles, is a female form intended to bring to mind the Diadumenos, the renowned Greek sculpture of an athlete crowning himself with the victor's ribbon diadem.
Edwardsiella lineata, the lined anemone, is a species of sea anemone in the family Edwardsiidae. It is native to the northwestern Atlantic Ocean where it occurs in the subtidal zone.
Haloclava is a genus of sea anemones in the family Haloclavidae. Members of this genus typically burrow into soft sediment.
Paranthus rapiformis, the onion anemone, is a species of sea anemone in the family Actinostolidae. It was first described by the French naturalist Charles Alexandre Lesueur in 1817 and is native to the northwestern Atlantic Ocean and the Gulf of Mexico.
Mesacmaea mitchellii is a species of sea anemone in the family Haloclavidae. It is found in the northeastern Atlantic Ocean and the Mediterranean Sea where it burrows in soft sediment.
Edwardsia neozelanica, commonly known as the burrowing anemone, is a small cryptic sea anemone from New Zealand. It burrows into soft mud or sand, and when covered with water extends its tentacles to feed on tiny particles of detritus.
