Bioluminescence is the production and emission of light by living organisms. It is a form of chemiluminescence. Bioluminescence occurs widely in marine vertebrates and invertebrates, as well as in some fungi, microorganisms including some bioluminescent bacteria, and terrestrial arthropods such as fireflies. In some animals, the light is bacteriogenic, produced by symbiotic bacteria such as those from the genus Vibrio; in others, it is autogenic, produced by the animals themselves.
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.
Siphonophorae is an order within Hydrozoa, which is a class of marine organisms within the phylum Cnidaria. According to the World Register of Marine Species, the order contains 175 species described thus far.
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.
Botryllus schlosseri is a colonial ascidian tunicate. It is commonly known as the star tunicate, but it also has several other common names, including star ascidian and golden star tunicate. Colonies grow on slow-moving, submerged objects, plants, and animals in nearshore saltwater environments.
A zooid or zoöid is a single animal that is part of a colonial animal. This lifestyle has been adopted by animals from separate unrelated taxa. Zooids are multicellular; their structure is similar to that of other solitary animals. The zooids can either be directly connected by tissue or share a common exoskeleton. The colonial organism as a whole is called a zoon, plural zoa.
Praya dubia, the giant siphonophore, lives in the mesopelagic zone to bathypelagic zone at 700 m (2,300 ft) to 1,000 m (3,300 ft) below sea level. It has been found off the coasts around the world, from Iceland in the North Atlantic to Chile in the South Pacific.
Pyrosoma is a genus of pyrosomes, marine colonial tunicates in the class Thaliacea. It contains four pelagic species found in temperate waters worldwide. Pyrosomes are filter feeders that uniquely use a type of continuous jet propulsion, generated by individual zooids, to slowly move forward while grazing; the species P. atlanticum has the highest known food clearance rate among zooplankton grazers. Colonies can reach lengths of up to 20 m (66 ft).
Pycnoclavella diminuta, known as the white-spotted sea squirt, white-spot ascidian, and white-spotted ascidian, is a species of tunicate, in the genus Pycnoclavella. Like all ascidians, these sessile animals are filter feeders.
Pyrosoma atlanticum is a pelagic species of marine colonial tunicate in the class Thaliacea found in temperate waters worldwide. The name of the genus comes from the Greek words pyros meaning 'fire' and soma meaning 'body', referring to the bright bioluminescence sometimes emitted. The specific epithet atlanticum refers to the Atlantic Ocean, from where the first specimen of the species was collected for scientific description; it was described in 1804 by François Péron, a French naturalist.
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 aurantium is a species of colonial sea squirt, a tunicate in the family Polyclinidae. It is native to shallow water in the northeastern Atlantic Ocean and Mediterranean Sea.
Stolonica socialis is a species of tunicate or sea squirt in the family Styelidae, commonly known as orange sea grapes. It is native to the northeastern Atlantic Ocean, where it lives on the rocky seabed in shallow water.
Clavelina minuta is a species of sea squirt found in Japan, that has been demonstrated to produce an intrinsic (non-secreted) green bioluminescence of 535 nm. Notably, this bioluminescence is not thought to be due to bacterial symbionts. Clavelina minuta is currently the only sea squirt (Ascidiacea) known to produce light, however old reports also report luminescence in Botryllus and Ciona. Amongst other tunicates, the unrelated Pyrosoma and Appendicularia, which produce an intrinsic blue light, are bioluminescent, and genera Doliolum (Doliolidae) and Cyclosalpa (Salpidae) may also be bioluminescent.
Pyrosomella is a genus of pyrosome that is usually smaller than typical pyrosoma.
Pyrosomella verticillata, the fire salp, is a species of colonial pyrosome with an Indo-Pacific distribution.
