Polycarpa fibrosa

Polycarpa fibrosa
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Subphylum:	Tunicata
Class:	Ascidiacea
Order:	Stolidobranchia
Family:	Styelidae
Genus:	Polycarpa
Species:	P. fibrosa
Binomial name
	Polycarpa fibrosa; (Stimpson, 1852)
Synonyms
	Glandula fibrosaStimpson, 1852; Glandula tubularisSars, 1859; Pandocia fibrosa(Stimpson, 1852); Tethyum fibrosum(Stimpson, 1852);

Last updated October 26, 2024

Polycarpa fibrosa is a species of tunicate in the family Styelidae. It is brown and globular and its outer surface is covered with a mat of fibrils. It normally lies buried in soft sediment on the seabed with only its two siphons protruding. It occurs in the Arctic Ocean and northern Atlantic Ocean. P. fibrosa was first identified and described by the American malacologist William Stimpson in 1852.

Description

Polycarpa fibrosa is globular or ovoid in shape and is about 35 mm (1.4 in) in diameter. It has a sac-like body with a tough covering known as a tunic, and is densely clad in short fibrils. There are two long, tapering, four-lobed siphons on the upper surface. Water is drawn into the body cavity through one of these, the buccal siphon, and expelled through the atrial siphon. The buccal siphon has a ring of up to 60 tentacles round the rim. These function to prevent particles that are too large from being drawn into the body cavity. This tunicate is a brownish colour and is well camouflaged, as particles of sand, shell fragments and mud adhere to the fibrils. It is usually partially buried in the sediment on the seabed with the two siphons projecting.^[2]

Distribution

This species is found in the boreal-arctic region. Its range includes the Arctic Ocean and North Atlantic, the Mediterranean Sea, the North Sea, the Gulf of Saint Lawrence, the Bay of Fundy and the Gulf of Maine.^[1] It lives loosely attached to the seabed on soft sediment at depths varying between shallow water and over 1,000 metres (3,300 ft).^[2] It prefers clean gravel, or coarse sand and shell gravel, which is in contrast to the rather similar Molgula occulta which favours muddy sediments and Molgula oculata which is found among coarser material.^[3]

Biology

Polycarpa fibrosa is a hermaphrodite and is viviparous. Sperm is shed into the sea and sucked in through the buccal siphon of another individual, a batch of eggs is liberated from the oviduct, and fertilisation takes place within the body cavity. The eggs are opaque with pigmented yolks and are about 0.16 mm (0.006 in) in diameter. The developing embryos are brooded in the body cavity.^[4] Hatching is initiated by the release of enzymes which rupture the egg membranes. The larvae have notochords (stiffening rods) and resemble salamander tadpoles. They have fluid-filled sensory organs known as otocysts. The larvae continue to be brooded at first but are later liberated into the sea.^[4] After a short free-swimming period, they sink to the seabed, their tails are absorbed, they lose their notochords and undergo metamorphosis into the adult form.^[4]

Related Research Articles

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.

Corella willmeriana is a solitary tunicate in the family Corellidae. It is native to the eastern Pacific Ocean where it lives on the seabed at depths down to about 75 m (250 ft) between Alaska and California.

Clavelina picta, common name the painted tunicate, is a species of tunicate, in the genus Clavelina. These animals, like all ascidians, are sessile filter feeders.

<i>Ecteinascidia turbinata</i> Species of sea squirt

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.

Atriolum robustum is a colonial tunicate or sea squirt in the family Didemnidae. It is native to the western and central Indo-Pacific where it is usually found anchored to a hard surface in shallow water.

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.

Didemnum vexillum is a species of colonial tunicate in the family Didemnidae. It is commonly called sea vomit, marine vomit, pancake batter tunicate, or carpet sea squirt. It is thought to be native to Japan, but it has been reported as an invasive species in a number of places in Europe, North America and New Zealand. It is sometimes given the nickname "D. vex" because of the vexing way in which it dominates marine ecosystems when introduced into new locations; however, the species epithet vexillum actually derives from the Latin word for flag, and the species was so named because of the way colonies' long tendrils appear to wave in the water like a flag.

Molgula oculata, commonly known as the sea grape, is a species of solitary tunicate in the family Molgulidae. It is native to the north eastern Atlantic Ocean and the North Sea. The specific name oculata means "having eyes"; the species has orifices which "seem like dark eyes within a spectacle-formed frame".

Molgula occulta is a species of solitary tunicate in the family Molgulidae. It is native to the north eastern Atlantic Ocean, the North Sea and the Mediterranean Sea. The specific name occulta means "tailless" and refers to the tunicate's larva, which lacks the tail found in some other species in the genus Molgula.

Molgula citrina is a species of solitary tunicate in the family Molgulidae. It is found on both sides of the northern Atlantic Ocean and in the Arctic Ocean. In 2008 it was found in Kachemak Bay in Alaska, the first time it had been detected in the Pacific Ocean.

Polycarpa pomaria is a species of tunicate or sea squirt in the family Styelidae. It is native to the northeastern Atlantic Ocean where it lives on the seabed at depths down to about 450 metres (1,500 ft).

Dendrodoa grossularia is a species of tunicate or sea squirt in the family Styelidae, commonly known as the baked bean ascidian. It is native to the northeastern Atlantic Ocean where it is common in shallow water and on the lower shore in exposed rocky sites.

Distomus variolosus is a species of tunicate or sea squirt in the family Styelidae. It is native to the northeastern Atlantic Ocean where it lives on the seabed, typically on the stems and fronds of kelp.

Corella eumyota, the orange-tipped sea squirt, is a solitary tunicate in the family Corellidae. It is native to the Southern Ocean, the Antarctic, South America, southern Australia, New Zealand and South Africa, and has been introduced into European waters where it has become invasive.

Molgula occidentalis is a species of marine invertebrate of the family Molgulidae. The scientific name of the species was validated and published for the first time in 1883 by Traustedt. It is a soft-bodied, intertidal ascidian, sac-like filter feeders in the subphylum tunicate characterized by a hard outer covering known as a “tunic,” abundant in the shallow subtidal and intertidal zones of the Northern Gulf of Mexico, where they establish pseudopopulations.

Boltenia villosa is a species of tunicate, a marine invertebrate of the family Pyuridae. Common names include spiny-headed tunicate, hairy sea squirt, stalked hairy sea squirt and bristly tunicate. This species was first described in 1864 by the American marine biologist William Stimpson who gave it the name Cynthia villosa. It was later transferred to the genus Boltenia. The type locality is Puget Sound, Washington state, United States.

Pyura haustor is a species of sessile ascidian, or sea squirt, that lives in coastal waters in the north-eastern Pacific Ocean, attached to rocks or artificial structures. Common names for this species include the wrinkled seapump, the wrinkled sea squirt and the warty tunicate.

Tunicotheres is a monotypic genus of crabs in the family Pinnotheridae, and Tunicotheres moseri is the only species in the genus. This crab lives commensally in the atrial chamber of a small ascidian. It is found in the tropical western Atlantic Ocean, the Caribbean Sea and the Gulf of Mexico.

Halocynthia igaboja, commonly known as sea hedgehog, bristly tunicate or spiny sea squirt, is a species of tunicate in the family Pyuridae. It is native to the northeastern Pacific Ocean. This species was first described in 1906 by the Japanese marine biologist Asajiro Oka, who gave it the name Cynthia ritteri. It was later transferred to the genus Halocynthia.

References

1 2 Karen Sanamyan (2012). "Polycarpa fibrosa (Stimpson, 1852)". WoRMS. World Register of Marine Species . Retrieved 2015-01-12.
1 2 "Polycarpa fibrosa". Macrobenthos of the North Sea: Tunicata. Marine Species Identification Portal. Retrieved 2015-01-12.
↑ Picton, B.E.; Morrow, C.C. (2010). "Polycarpa fibrosa". Encyclopedia of Marine Life of Britain and Ireland. Retrieved 2015-01-14.
1 2 3 Berrill, N. J. (1930). "Studies in Tunicate Development. Part I. General Physiology of Development of Simple Ascidians". Philosophical Transactions of the Royal Society of London B. 218: 37–78. doi: 10.1098/rstb.1930.0002 . JSTOR 92217.

This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.

[WoRMS-1] 1 2 Karen Sanamyan (2012). "Polycarpa fibrosa (Stimpson, 1852)". WoRMS. World Register of Marine Species . Retrieved 2015-01-12.

[MSIP-2] 1 2 "Polycarpa fibrosa". Macrobenthos of the North Sea: Tunicata. Marine Species Identification Portal. Retrieved 2015-01-12.

[3] Picton, B.E.; Morrow, C.C. (2010). "Polycarpa fibrosa". Encyclopedia of Marine Life of Britain and Ireland. Retrieved 2015-01-14.

[Berrill-4] 1 2 3 Berrill, N. J. (1930). "Studies in Tunicate Development. Part I. General Physiology of Development of Simple Ascidians". Philosophical Transactions of the Royal Society of London B. 218: 37–78. doi: 10.1098/rstb.1930.0002 . JSTOR 92217.

[1]

[2]

[3]

[4]