|
Hexacorallia
Hexacorallia is a Class (biology), class of Anthozoa comprising approximately 4,300 species of aquatic organisms formed of polyp (zoology), polyps, generally with 6-fold symmetry. It includes all of the stony corals, most of which are Colony (biology), colonial and reef-forming, as well as all sea anemones, and zoanthids, arranged within five extant Order (biology), orders. The hexacorallia are distinguished from another class of Anthozoa, Octocorallia, in having six or fewer axes of symmetry in their body structure; the tentacles are simple and unbranched and normally number more than eight. These organisms are formed of individual soft polyps which in some species live in colonies and can secrete a calcite skeleton. As with all Cnidarians, these organisms have a complex life cycle including a motile planktonic phase and a later characteristic Sessility (zoology), sessile phase. Hexacorallia also include the significant extinct order of rugose corals. Phylogeny Hexacorallia is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anthozoa
Anthozoa is a subphylum of marine invertebrates which includes the sea anemones, Scleractinia, stony corals and Alcyonacea, 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 (zoology), 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 Colony (biology), 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. Anthozoa is included within the phylum Cnidaria, which also includes the jellyfish, Box jellyfish, box jellies and parasitic Myxozoa and Polypodiozoa. The two main subclasses of Anthozoa are the Hexacorallia, members of which have six-fold symmetry in biology, symmetry and includes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zoantharia
Zoanthids ( order Zoantharia also called Zoanthidea or Zoanthiniaria) are an order of cnidarians commonly found in coral reefs, the deep sea and many other marine environments around the world. These animals come in a variety of different colonizing formations and in numerous different colors. They can be found as individual polyps, attached by a fleshy stolon or a mat that can be created from small pieces of sediment, sand and rock. The term "zoanthid" refers to all animals within this order Zoantharia, and should not be confused with "'' Zoanthus''", which is one genus within Zoantharia. These are among the most commonly collected corals in reef aquaria, easily propagating and very durable in many water conditions. Nomenclature controversy The name of the order is controversial. Non-specialists often use the term Zoanthidea whereas most taxonomists use Zoantharia. The term Zoantharia in turn is used temporarily instead of Hexacorallia. However, major taxonomic papers published ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zoanthids
Zoanthids ( order Zoantharia also called Zoanthidea or Zoanthiniaria) are an order of cnidarians commonly found in coral reefs, the deep sea and many other marine environments around the world. These animals come in a variety of different colonizing formations and in numerous different colors. They can be found as individual polyps, attached by a fleshy stolon or a mat that can be created from small pieces of sediment, sand and rock. The term "zoanthid" refers to all animals within this order Zoantharia, and should not be confused with "'' Zoanthus''", which is one genus within Zoantharia. These are among the most commonly collected corals in reef aquaria, easily propagating and very durable in many water conditions. Nomenclature controversy The name of the order is controversial. Non-specialists often use the term Zoanthidea whereas most taxonomists use Zoantharia. The term Zoantharia in turn is used temporarily instead of Hexacorallia. However, major taxonomic papers published ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hexacorallia
Hexacorallia is a Class (biology), class of Anthozoa comprising approximately 4,300 species of aquatic organisms formed of polyp (zoology), polyps, generally with 6-fold symmetry. It includes all of the stony corals, most of which are Colony (biology), colonial and reef-forming, as well as all sea anemones, and zoanthids, arranged within five extant Order (biology), orders. The hexacorallia are distinguished from another class of Anthozoa, Octocorallia, in having six or fewer axes of symmetry in their body structure; the tentacles are simple and unbranched and normally number more than eight. These organisms are formed of individual soft polyps which in some species live in colonies and can secrete a calcite skeleton. As with all Cnidarians, these organisms have a complex life cycle including a motile planktonic phase and a later characteristic Sessility (zoology), sessile phase. Hexacorallia also include the significant extinct order of rugose corals. Phylogeny Hexacorallia is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sea Anemone
Sea anemones are a group of predation, predatory marine invertebrates of the order (biology), order Actiniaria. Because of their colourful appearance, they are named after the ''Anemone'', a terrestrial flowering plant. 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 (genus), Hydra''. Unlike jellyfish, sea anemones do not have a Jellyfish#Life history and behavior, medusa stage in their life cycle. A typical sea anemone is a single polyp (zoology), polyp attached to a hard surface by its base, but some species live in soft sediment, and a few float near the surface of the water. The polyp has a columnar trunk topped by an oral disc with a ring of tentacles and a central mouth. The tentacles can be retracted inside the body cavity or expanded to catch passing prey. They are armed with cnidocytes (stinging cells). In many species, additional n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Actiniaria
Sea anemones are a group of predatory marine invertebrates of the order Actiniaria. Because of their colourful appearance, they are named after the ''Anemone'', a terrestrial flowering plant. 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. A typical sea anemone is a single polyp attached to a hard surface by its base, but some species live in soft sediment, and a few float near the surface of the water. The polyp has a columnar trunk topped by an oral disc with a ring of tentacles and a central mouth. The tentacles can be retracted inside the body cavity or expanded to catch passing prey. They are armed with cnidocytes (stinging cells). In many species, additional nourishment comes from a symbiotic relationship with single-celled dinoflagellates, with zooxa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antipatharia
Antipatharians, also known as black corals or thorn corals, are an order of soft deep-water corals. These corals can be recognized by their jet-black or dark brown chitin skeletons, surrounded by the polyps (part of coral that is alive). Antipatharians are a cosmopolitan order, existing at nearly every location and depth, with the sole exception of brackish waters. However, they are most frequently found on continental slopes under deep. A black coral reproduces both sexually and asexually throughout its lifetime. Many black corals provide housing, shelter, food, and protection for other animals. Black corals were originally classified in the subclass Ceriantipatharia along with ceriantharians (tube-dwelling anemones), but were later reclassified under Hexacorallia. Though they have historically been used by Pacific Islanders for medical treatment and in rituals, its only modern use is making jewelry. Black corals have been declining in numbers and are expected to continue de ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cnidaria
Cnidaria () is a phylum under kingdom Animalia containing over 11,000 species of aquatic animals found both in freshwater and marine environments, predominantly the latter. Their distinguishing feature is cnidocytes, specialized cells that they use mainly for capturing prey. Their bodies consist of mesoglea, a non-living jelly-like substance, sandwiched between two layers of epithelium that are mostly one cell thick. Cnidarians mostly have two basic body forms: swimming medusae and sessile polyps, both of which are radially symmetrical with mouths surrounded by tentacles that bear cnidocytes. Both forms have a single orifice and body cavity that are used for digestion and respiration. Many cnidarian species produce colonies that are single organisms composed of medusa-like or polyp-like zooids, or both (hence they are trimorphic). Cnidarians' activities are coordinated by a decentralized nerve net and simple receptors. Several free-swimming species of Cubozoa and Scyphozo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coral
Corals are marine invertebrates within the class 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. A coral "group" is a colony of very many genetically identical polyps. Each polyp is a sac-like animal typically only a few millimeters in diameter and a few centimeters in height. A set of tentacles surround a central mouth opening. Each polyp excretes an exoskeleton near the base. Over many generations, the colony thus creates a skeleton characteristic of the species which can measure up to several meters in size. Individual colonies grow by asexual reproduction of polyps. Corals also breed sexually by spawning: polyps of the same species release gametes simultaneously overnight, often around a full moon. Fertilized eggs form planulae, a mobile early form of the coral polyp which, when m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scleractinia
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 polyp (zoology), 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 Colony (biology), colonial. The founding polyp settles and starts to secrete calcium carbonate to protect its soft body. Solitary corals can be as much as 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 cloning, clones with a common skeleton, which may be up to several metres in diameter or height according to species. The shape and appearance of each coral colony depends not only on the species, but also on its location, depth, the amount of water movement and other factors. Many shallow-water co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Corallimorpharia
Corallimorpharia is an order of marine cnidarians closely related to stony or reef building corals (Scleractinia). They occur in both temperate and tropical climates, although they are mostly tropical. Temperate forms tend to be very robust, with wide and long columns, whereas tropical forms tend to have very short columns with a wide oral disc and very short tentacles. The tentacles are usually arranged in rows radiating from the mouth. Many species occur together in large groups, although there are recorded instances of individuals. In many respects, they resemble the stony corals, except for the absence of a stony skeleton. Morphological and molecular evidence suggests that they are very closely related to stony corals. Corallimorpharians occur in a wide range of marine habitats, and can be associated with phase shifts in coral reef ecosystems that result in a change from a hard-coral dominated reef to a soft-coral dominated one. They have been observed to overgrow reefs in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tabulata
Tabulata, commonly known as tabulate corals, are an order of extinct forms of coral. They are almost always colonial, forming colonies of individual hexagonal cells known as corallites defined by a skeleton of calcite, similar in appearance to a honeycomb. Adjacent cells are joined by small pores. Their distinguishing feature is their well-developed horizontal internal partitions (''tabulae'') within each cell, but reduced or absent vertical internal partitions ( ''septa''). They are usually smaller than rugose corals, but vary considerably in shape, from flat to conical to spherical. Around 300 species have been described. Among the most common tabulate corals in the fossil record are ''Aulopora'', ''Favosites'', ''Halysites'', ''Heliolites'', ''Pleurodictyum'', ''Sarcinula'' and '' Syringopora''. Tabulate corals with massive skeletons often contain endobiotic symbionts, such as cornulitids and ''Chaetosalpinx''. Like rugose corals, they lived entirely during the Paleozoi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
