| Orange-striped sea anemone | |
|---|---|
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Scientific classification  | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Cnidaria |
| Class: | Hexacorallia |
| Order: | Actiniaria |
| Family: | Diadumenidae |
| Genus: | Diadumene |
| Species: | D. lineata |
| Binomial name | |
| Diadumene lineata | |
| Synonyms [1] | |
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Diadumene lineata, the orange-striped green sea anemone, has several morphotypes which have been described multiple times. [2]
This is a smaller species, measuring approximately 3.5 centimeters in diameter across its tentacles and 3 centimeters in height. Its central column is green-gray to brown color and smooth. The column, which houses the gastro vascular central cavity extends from the mouth to the attached base called the pedal disc. It does not always have vertical stripes, which can be orange or white. There are 50 to 100 slender and tapered tentacles which are able to retract completely into the column. They are commonly transparent and can be gray or light green with white flecks (Christine 2001). Many morphs occur for this species: Sagartia lineata (Verill, 1869 Hong Kong), Diadumene lineata (Verill 1870); Diaumene luciae (Stephenson, 1925); Haliplanella luciae (Hand, 1955); Properly named D. lineata (Hand 1989). In a single population there may be one or several functioning variations of the species description (Hand, 1955b; Williams, 1973b). [3] [4] Population studies exhibiting morphs of several different communities were done along with personal communication from the following individuals (Parker 1919, Allee 1923, Stephenson 1935). An un-striped population was found by D.F. Dunn in San Francisco Bay, California. Two morphs were found, one with twelve orange stripes on a green-brown column and one with 48 paired white stripes on a green column. These population studies were done in Indian Field Creek, Virginia and Barnstable Town Dock, Massachusetts by C.P. Mangum.
This species originated from the Pacific coast of Asia, but is currently found in the Northern Hemisphere. It has been found in Japan, [5] the Gulf of Mexico (Verrill), Plymouth and Wells, Norfolk, England (R.B. Williams), Western Europe, [6] the Mediterranean Sea, the Suez Canal, Malaysia (D. F. Dunn, California Academy of Sciences), and North America on the East Coast from Maine to Florida (L. L. Minasian, Myers 1977, Stephenson 1935, Sassaman and Mangum 1970, Shick, J. H. Ting 1983, Uchida 1932, G. M. Watson, W. E. Zamer 1999). [7] It has also been found in Hawaii and other sites of the Pacific Ocean. [8] Recently it has appeared in Argentina and other localities of South America. [9] Distribution away from Asia may have occurred by attachment to ship bottoms, oyster shipments, and seaweed. These anemones target ecosystems that are barren landscapes or with low species diversity. Appearing suddenly, populations quickly proliferate and colonize zones and alter natural balances. Within short durations, they are known to vanish from the area quickly with no warning (Stephenson 1953). It is a member of the fouling community, but does not cause significant economic impacts.
Diadumene anemones display high tolerance to inter-tidal exposure and drying out in extreme summer heat. They form encystments when locked in freezing climates. They acclimatize to severely low salinities. In Blue Hill Flls, Maine 100 percent survival of a population of 4000 individuals was observed after two weeks of temperatures of 1.0°- 27.5 °C, and salinities of 0.5 - 35‰. [10]
Physiological races, which are eurytolerant (tolerant of extreme environments) diverse species, that exhibit different resistances in remote and secluded places. [11] This species demonstrates strong genetic selection of certain physiological strains (Prosser 1957).
While this sea anemone can reproduce sexually, it normally reproduces asexually by longitudinal fission. The asexual process is where a new polyp develops from a portion of the original polyp after pulling away (anemone splits in half). In many localities, there is little or no genetic variability between individual polyps as they are all clones of each other. This leads to a situation where apparently thriving populations can suddenly vanish from a locality. This happens because there is a lack of genetic variability among the population, and as the limits of tolerance of some parameter is approached, there is a sudden incidence of mortality among the whole population. [12]
Anemones, like all cnidarians, have nematocysts, which are stinging organelles used for defense and catching prey. Studies of nematocyst development on tentacle tips of this and several species reveals several different stages of tentacle morphology (Watson and Mariscal, Florida State University 1983). Comparisons to hydrozoans in terms of growth stages or bulb pulses of tentacle development are explained by growth of individual tentacles by widening or an increasing length of the column (Campbell 1980). The nematocysts are found on both catch tentacles and feeding tentacles. The catch tentacles used for aggression and capturing of prey have larger length and width than feeding tentacles, which aid in the capture of food. Feeding tentacles are displaced by catch tentacles during growth cycles, and migrate towards the central column. This is commonly found in aggressive sea anemones who share food sources. [13] During aggressive interactions, individual catch tentacles will strike a non-clone-mate in the upper column or tentacles. They break when withdrawn, separating the nematocyst—containing tip from the remaining tentacle. This can have life-threatening consequences, such as necrosis (cellular death) for the struck organism.
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 a 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.
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.
Heteractis magnifica, also known by the common names magnificent sea anemone or Ritteri anemone, is a species of sea anemone belonging to the Stichodactylidae family native to the Indo-Pacific area.
The aggregating anemone, or clonal anemone, is the most abundant species of sea anemone found on rocky, tide swept shores along the Pacific coast of North America. This cnidarian hosts endosymbiotic algae called zooxanthellae that contribute substantially to primary productivity in the intertidal zone. The aggregating anemone has become a model organism for the study of temperate cnidarian-algal symbioses.
Bubble-tip anemone is a species of sea anemone in the family Actiniidae. Like several anemone species, E. quadricolor can support several anemonefish species, and displays two growth types based on where they live in the water column, one of which gives it the common name, due to the bulbous tips on its tentacles.
Hexacorallia is a class of Anthozoa comprising approximately 4,300 species of aquatic organisms formed of polyps, generally with 6-fold symmetry. It includes all of the stony corals, most of which are colonial and reef-forming, as well as all sea anemones, and zoanthids, arranged within five extant 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 sessile phase. Hexacorallia also include the significant extinct order of rugose corals.
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 a group of predatory marine invertebrates constituting 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.
Epiactis prolifera, the brooding, proliferating or small green anemone, is a species of marine invertebrate in the family Actiniidae. It is found in the north-eastern Pacific. It has a feature rare among animals in that all individuals start life as females but develop testes later in their lives to become hermaphrodites.
Epiactis is a genus of sea anemones in the family Actiniidae. There are about nineteen recognised species and the type species is Epiactis prolifera.
Sagartia ichthystoma is a species of sea anemone in the family Sagartiidae, also known as the fish-mouth anemone. The species name refers to the short pointed tentacles round the edge of the disc which resemble the sharp teeth of certain fish.
Sagartia elegans, the elegant anemone, is a species of sea anemone in the family Sagartiidae. It is found in coastal areas of northwest Europe at depths down to 50 metres.
Metridium farcimen is a species of sea anemone in the family Metridiidae. It is commonly known as the giant plumose anemone or white-plumed anemone. It is found in the eastern Pacific Ocean from Alaska down to Catalina Island, California.
Lebrunia coralligens, commonly known as the hidden anemone, is a species of sea anemone in the family Aliciidae. It is found in shallow water in the Bahamas, the Caribbean, and Brazil. It lives in fissures in corals and rocks.
The Enthemonae is a suborder of sea anemones in the order Actiniaria. It comprises those sea anemones with typical arrangement of mesenteries for actiniarians.
Diadumene cincta is a small and delicate, usually orange, sea anemone. It has a smooth slender column and up to 200 long tentacles, and normally grows to a length of up to 35 mm (1.4 in), with a base of 10 mm (0.4 in), but specimens twice this size have been recorded. Diadumene cincta is found in the northeastern Atlantic Ocean.
Actinostola callosa is a species of sea anemones in the family Actinostolidae in the order Actiniaria. It is a deep sea species and occurs in both Pacific and Atlantic Oceans from the continental shelf to abyssal depths.
Diadumene is a genus of sea anemones. It is the only genus in the monotypic family Diadumenidae.
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.