Actinia cari | |
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Scientific classification | |
Kingdom: | Animalia |
Phylum: | Cnidaria |
Class: | Hexacorallia |
Order: | Actiniaria |
Family: | Actiniidae |
Genus: | Actinia |
Species: | A. cari |
Binomial name | |
Actinia cari Delle Chiaje, 1822 | |
Actinia cari is a species of sea anemone in the family Actiniidae. [1] It is native to the Mediterranean Sea where it is an uncommon species.
Actinia cari grows to approximately 4-5 centimetres wide, and 8 centimetres high. It can fully retract its tentacles. It has a brown-green to reddish colour, [2] with concentric, dark, longitudinal rings on the body wall, [3] and is roughly cylindrical to conical in shape. [4]
This is a common species that occurs mainly in the Mediterranean Sea, and can also be found in the adjacent parts of the Atlantic Ocean. [5] Actinia cari lives in rocky areas, attaching itself to rocks and the underside of smooth stones. It is a common species and is found in the infralittoral zone and the subtidal zone to a depth of a few metres. [6]
This is a nocturnal species. [7] It catches small prey with its tentacles.
This sea anemone contains toxins that can be extracted by the "milking" method using gel and ion exchange chromatography. Two hemolytic polypeptides have been extracted in this manner. The two caritoxins, known as CTX I and CTX II, had a similar compositions of amino acids which did not include cysteine. The molecular weight of the pure toxin was found to be 19,800 daltons. The lethal dose (LD50) for mice injected intravenously, was found to be 54 μg/kg for CTX 1 and 90 μg/kg for CTX II. [8] Another caritoxin, CTX III, has also been isolated using controlled autolysis of the tentacles through a nylon sieve, and separated using gel chromatography. This had a molecular weight in the range 20,000 to 25,000 daltons. The hemolytic activity of all three caritoxins was permanently and irreversibly inhibited by sphingomyelin. [9]
Tube-dwelling anemones or ceriantharians look very similar to sea anemones but belong to an entirely different subclass of anthozoans. They are solitary, living buried in soft sediments. Tube anemones live inside and can withdraw into tubes, which are composed of a fibrous material made from secreted mucus and threads of nematocyst-like organelles known as ptychocysts. Within the tubes of these ceriantharians, more than one polyp is present, which is an exceptional trait because species that create tube systems usually contain only one polyp per tube. Ceriantharians were formerly classified in the taxon Ceriantipatharia along with the black corals but have since been moved to their own subclass, Ceriantharia.
Actinia fragacea, commonly known as the strawberry anemone, is a species of sea anemone of the order Actiniaria, that occurs from Norway to Africa, including adjacent islands and the Mediterranean. It is generally found on rocks of the lower shoreline and depths up to 8–10 metres (26–33 ft).
The beadlet anemone is a common sea anemone found on rocky shores around all coasts of the British Isles. Its range extends to the rest of Western Europe and the Mediterranean Sea, and along the Atlantic coast of Africa as far south as South Africa.
Corynactis californica is a brightly colored colonial anthozoan corallimorph. Unlike the Atlantic true sea anemone, Actinia fragacea, that bears the same common name, strawberry anemone, this species is a member of the order Corallimorpharia, and is the only member found in the North American West Coast. Other common names include club-tipped anemone and strawberry corallimorpharian. The anemone can live up to at least 50 meters deep on vertical rock walls, and at the bottom of kelp forests. It is known to carpet the bottom of some areas, like Campbell River in British Columbia, and Monterey Bay in California.
Anemonia sulcata, or Mediterranean snakelocks sea anemone, is a species of sea anemone in the family Actiniidae from the Mediterranean Sea. Whether A. sulcata should be recognized as a synonym of A. viridis remains a matter of dispute.
Sea anemones are a group of predatory marine animals 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.
Condylactis gigantea is a tropical species of ball anemone that is found in shallow reefs and other shallow inshore areas in the Caribbean Sea – more specifically the West Indies – and the western Atlantic Ocean including southern Florida through the Florida Keys. It is also commonly known as: giant Caribbean sea anemone, giant golden anemone, condylactis anemone, Haitian anemone, pink-tipped anemone, purple-tipped anemone, and Florida condy. This species can easily be seen growing in lagoons or in inner reefs as either individuals or loose groups, but never as colonies. They are often used as a model organism along with others in their genus for facultative symbiosis with monocellular algae.
Stichodactyla helianthus, commonly known as sun anemone, is a sea anemone of the family Stichodactylidae. Helianthus stems from the Greek words ἡλιος, and ἀνθος, meaning flower. S. helianthus is a large, green, sessile, carpet-like sea anemone, from the Caribbean. It lives in shallow areas with mild to strong currents.
AETX refers to a group of polypeptide neurotoxins isolated from the sea anemone Anemonia erythraea that target ion channels, altering their function. Four subtypes have been identified: AETX I, II, III and K, which vary in their structure and target.
Calliactis parasitica is a species of sea anemone associated with hermit crabs. It lives in the eastern Atlantic Ocean and Mediterranean Sea at depths between the intertidal zone and 60 m (200 ft). It is up to 10 cm × 8 cm in size, with up to 700 tentacles, and is very variable in colour. The relationship between C. parasitica and the hermit crab is mutualistic: the sea anemone protects the hermit crab with its stings, and benefits from the food thrown up by the hermit crab's movements.
In molecular biology, the sea anemone cytotoxic proteins are lethal pore-forming proteins, known collectively as actinoporins, a sub-class of cytolysins. There are several different groups of cytolysins based on their structure and function. This entry represents the most numerous group, the 20kDa highly basic peptides. These cytolysins form cation-selective pores in sphingomyelin-containing membranes. Examples include equinatoxins, sticholysins, magnificalysins, and tenebrosins, which exhibit pore-forming, haemolytic, cytotoxic, and heart stimulatory activities.
Holothuria forskali, the black sea cucumber or cotton-spinner, is a species of sea cucumber in the family Holothuriidae. It is found at shallow depths in the eastern Atlantic Ocean and the Mediterranean Sea. It was placed in the subgenus Panningothuria by Rowe in 1969 and is the typetaxon of the subgenus.
Actinia is a genus of sea anemones in the family Actiniidae. Actinia display a rare form of heteromorphosis in which a cut inflicted on a specimen can develop into a second mouth.
Cereus pedunculatus or the daisy anemone is a species of sea anemone in the family Sagartiidae. It is found in shallow parts of the northeast Atlantic Ocean and in the North Sea and the Mediterranean Sea. It is an omnivore, predator and scavenger.
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.
Actinia bermudensis, the red, maroon or stinging anemone, is a species of sea anemone in the family Actiniidae.
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.
Calitoxin, also known as CLX, is a sea anemone neurotoxin produced by the sea anemone Calliactis parasitica. It targets crabs and octopuses, among other invertebrates. Two isoforms have been identified, both of which are formed from precursors stored in the stinging cells of the anemone. Once the toxin is activated and released, it causes paralysis by increasing neurotransmitter release at invertebrate neuromuscular junctions. Along with several other toxins derived from anemones, CLX is useful in ion channel research. Certain structural aspects of calitoxin are dissimilar from sea anemone toxins that also target the sodium ion channels. Other toxins resembling calitoxin function in completely different ways.
SHTX is a toxin derived from the sea anemone Stichodactyla haddoni; there are four different subtypes, SHTX I, II, III and IV. SHTX I, II and III can paralyze crabs by acting on potassium channels, while SHTX IV works on sodium channels, and is lethal to crabs.
ATX-II, also known as neurotoxin 2, Av2, Anemonia viridis toxin 2 or δ-AITX-Avd1c, is a neurotoxin derived from the venom of the sea anemone Anemonia sulcata. ATX-II slows down the inactivation of different voltage-gated sodium channels, including Nav1.1 and Nav1.2, thus prolonging action potentials.