| Cyclosalpa bakeri | |
|---|---|
Scientific classification  | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Subphylum: | Tunicata |
| Class: | Thaliacea |
| Order: | Salpida |
| Family: | Salpidae |
| Genus: | Cyclosalpa |
| Species: | C. bakeri |
| Binomial name | |
| Cyclosalpa bakeri | |
Cyclosalpa bakeri is a salp, a marine tunicate in the class Thaliacea. It is found floating in the open sea in the Indo-Pacific region.
Like other salps, Cyclosalpa bakeri has two different phases. In one of these forms, individuals live a solitary life. They are cylindrical, transparent, gelatinous animals with a rather flabby test, growing to about 15 cm (6ins) long. There are openings at the anterior and posterior ends of the cylinder which can be opened or closed as needed. The bodies have seven transverse bands of muscle interspersed by white, translucent patches. A stolon grows from near the endostyle (an elongated glandular structure producing mucus for trapping food particles). The stolon is a ribbon-like organ on which a batch of aggregate forms of the animal are produced by budding. The aggregate is the second, colonial form of the salp and is also gelatinous, transparent and flabby. It takes the shape of a radial whorl of individuals up to about 20 cm (4 in) in diameter. It is formed of approximately 12 zooids linked side by side in a shape that resembles a crown. [2] [3]
Cyclosalpa bakeri has an Indo-Pacific distribution. Its range includes tropical and temperate waters and extends as far north as Alaska. [1]
Cyclosalpa bakeri moves by contracting its bands of muscles rhythmically at the same time opening and closing the front and rear openings appropriately. This squeezes water out from the hollow interior and the animal moves in the opposite direction, a form of jet propulsion. [3] This water movement brings in suspended phytoplankton which are caught by a mucus net. Cyclosalpa bakeri is an extremely efficient feeder. The aggregates can grow by a quarter of their size each day and individuals can eat more than half their body mass daily. [2]
Individuals within the aggregate are sequential hermaphrodites. They usually start life as females but later develop into males. [3] Eggs are produced by the females and are fertilised by sperm from another aggregate. There is no larval form and a single embryo develops in each individual in the aggregate. This later becomes detached from the aggregate and becomes a solitary individual ready to undergo asexual reproduction by budding again. The animal's rapid growth and this alternation of generations means that the population can build up rapidly when there is a plentiful food supply such as a bloom of phytoplankton. The salps themselves are eaten by fish, turtles, birds, jellyfish, heteropods, siphonophores and ctenophores. [2]
Zooplankton are the heterotrophic component of the planktonic community, having to consume other organisms to thrive. Plankton are aquatic organisms that are unable to swim effectively against currents. Consequently, they drift or are carried along by currents in the ocean, or by currents in seas, lakes or rivers.
A tunicate is an exclusively marine invertebrate animal, a member of the subphylum Tunicata. This grouping is part of the Chordata, a phylum which includes all animals with dorsal nerve cords and notochords. The subphylum was at one time called Urochordata, and the term urochordates is still sometimes used for these animals. They are the only chordates that have lost their myomeric segmentation, with the possible exception of the seriation of the gill slits. However, doliolids still display segmentation of the muscle bands.
Anthozoa is a subphylum of marine invertebrates which includes sessile cnidarians such as the sea anemones, stony corals, soft corals and sea pens. Adult anthozoans are almost all attached to the seabed, while their larvae can disperse as planktons. 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.
Thaliacea is a class of marine chordates within the subphylum Tunicata, comprising the salps, pyrosomes and doliolids. Unlike their benthic relatives the ascidians, from which they are believed to have emerged, thaliaceans are free-floating (pelagic) for their entire lifespan. The group includes species with complex life cycles, with both solitary and colonial forms.
Ascidiacea, commonly known as the ascidians or sea squirts, is a paraphyletic class in the subphylum Tunicata of sac-like marine invertebrate filter feeders. Ascidians are characterized by a tough outer "tunic" made of a polysaccharide.
The Doliolida are an order of small marine chordates of the subphylum Tunicata. They are in the class Thaliacea, which also includes the salps and pyrosomes. The doliolid body is small, typically 1–2 mm long, and barrel-shaped; it features two wide siphons, one at the front and the other at the back end, and eight or nine circular muscle strands reminiscent of barrel bands.
A salp or salpa is a barrel-shaped, planktonic tunicate in the family Salpidae. It moves by contracting, thereby pumping water through its gelatinous body; it is one of the most efficient examples of jet propulsion in the animal kingdom. The salp strains the pumped water through its internal feeding filters, feeding on phytoplankton.
Pyrosomes are free-floating colonial tunicates in family Pyrosomatidae. There are three genera, Pyrosoma, Pyrosomella and Pyrostremma, and eight species. They usually live in the upper layers of the open ocean in warm seas, although some may be found at greater depths.
Botrylloides leachii is a colonial tunicate of the family Styelidae. Its unique methods of propagation and regeneration make it an ideal model organism for use in biological study of development, immunology, stem cells, and regeneration.
Dolioletta is a genus of tunicates in the family Doliolidae.
Doliolidae is a family of tunicates in the order Doliolida. Members of the family are pelagic and often found far away from coastlines.
Dolioletta gegenbauri is a species of tunicate in the family Doliolidae. It is small, exists in various forms and is sometimes found in great abundance in the Atlantic and Pacific waters where it lives.
Aplidium californicum is a species of colonial sea squirt, a tunicate in the family Polyclinidae. It is commonly known as sea pork.
Aplidium solidum is a species of colonial sea squirts, a tunicate in the family Polyclinidae. It is commonly known as the red ascidian or sea pork.
Ecteinascidia turbinata, commonly known as the mangrove tunicate, is a species of tunicate in the family Perophoridae. It was described to science in 1880 by William Abbott Herdman. The cancer drug trabectedin can be isolated from this species.
Didemnum molle is a species of colonial tunicate in the family Didemnidae. It is commonly known as the tall urn ascidian, the green barrel sea squirt or the green reef sea-squirt. It is native to the Red Sea and the tropical waters of the Indo-Pacific region.
Ciona savignyi is a marine animal sometimes known as the Pacific transparent sea squirt or solitary sea squirt. It is a species of tunicates in the family Cionidae. It is found in shallow waters around Japan and has spread to the west coast of North America where it is regarded as an invasive species.
Perophora viridis, the honeysuckle tunicate, is a species of colonial sea squirt in the genus Perophora found in the tropical western Atlantic Ocean.
Thetys vagina, or the twin-sailed salp, is the largest known solitary species of salp and the only valid species of the genus Thetys. First described by W.G Tilesius in 1802, the species is transparent and gelatinous, making it difficult to be seen in water, which is helpful in avoiding predators. The fossil range is very recent. Other animals often mistaken for T. vagina are Salpa fusiformis, Aurelia aurita, and Pegea confoederata. There is no known status of conservation in this species. T. vagina DNA was sequenced as part of a larger project in 2014 where spiny lobster larvae were found attached to T. vagina and consuming it.
Polyclinum planum is a compound ascidian commonly known as the elephant ear tunicate. It is an ascidian tunicate in the family Polyclinidae. Ascidians are also known as sea squirts.