Parborlasia corrugatus
Encyclopedia
Parborlasia corrugatus is a proboscis worm
in the family Cerebratulidae. This species of proboscis or ribbon worm can grow to 2 metres (6.6 ft) in length, and lives primarily in marine environments down to 4000 metres (13,123.4 ft). It is a widely distributed scavenger
and predator.
as a means of defense, and to capture prey. This organ has adhesive secretion to aid in securing its meal.
Although this creature does not have a dedicated respiratory system, Parborlasia corrugatus is able to obtain oxygen by absorbing it through its skin. An animal of its size would typically find it difficult to receive enough oxygen this way, but this worm has a low metabolic rate, and also enjoys the advantage of its environment which is the cold Antarctic waters which are rich in oxygen. When Parborlasia corrugatus experiences lower levels of oxygen in the water, it flattens and elongates its body to aid in the uptake of oxygen by increasing its skin area. This manoevre also reduces the distance that the oxygen must travel to diffuse into its body.
Potential predators avoid this species as it has a chemical defense: acidic mucus with a pH
3.5.
to depths of up to 3,950 metres. It is found throughout the following areas:
Densities range greatly from 0.3 m−2 recorded in McMurdo Sound
, to the substantially higher densitiy of 26.2 m−2 around Signy Island
.
species broadcasts spawn. The resulting pilidium larvae
survive in the water column for up to 150 days.
and a predator, and feeds upon detritus diatoms, gastropods, amphipods, isopods, various vertebrate carrion sponges (including Homaxinella balfourensis), jellyfish
, seastars, molluscs, anemones, and polychaete worms.
Nemertea
Nemertea is a phylum of invertebrate animals also known as "ribbon worms" or "proboscis worms". Alternative names for the phylum have included Nemertini, Nemertinea and Rhynchocoela. Although most are less than long, one specimen has been estimated at , which would make it the longest animal ever...
in the family Cerebratulidae. This species of proboscis or ribbon worm can grow to 2 metres (6.6 ft) in length, and lives primarily in marine environments down to 4000 metres (13,123.4 ft). It is a widely distributed scavenger
Scavenger
Scavenging is both a carnivorous and herbivorous feeding behavior in which individual scavengers search out dead animal and dead plant biomass on which to feed. The eating of carrion from the same species is referred to as cannibalism. Scavengers play an important role in the ecosystem by...
and predator.
Description
Parborlasia corrugatus is smooth and flat. Adults measure 1–2 m (3.3–6.6 ), with a diameter of approximately 2 cm (0.78740157480315 in). Specimens can weigh up to 140 grams (4.9 oz). Their colouration is variable, ranging from cream through various tones of black. This worm has a wedge-shaped head containing a cavity filled with fluid. It uses this to fire an adhesive, barbed proboscisProboscis
A proboscis is an elongated appendage from the head of an animal, either a vertebrate or an invertebrate. In simpler terms, a proboscis is the straw-like mouth found in several varieties of species.-Etymology:...
as a means of defense, and to capture prey. This organ has adhesive secretion to aid in securing its meal.
Although this creature does not have a dedicated respiratory system, Parborlasia corrugatus is able to obtain oxygen by absorbing it through its skin. An animal of its size would typically find it difficult to receive enough oxygen this way, but this worm has a low metabolic rate, and also enjoys the advantage of its environment which is the cold Antarctic waters which are rich in oxygen. When Parborlasia corrugatus experiences lower levels of oxygen in the water, it flattens and elongates its body to aid in the uptake of oxygen by increasing its skin area. This manoevre also reduces the distance that the oxygen must travel to diffuse into its body.
Potential predators avoid this species as it has a chemical defense: acidic mucus with a pH
PH
In chemistry, pH is a measure of the acidity or basicity of an aqueous solution. Pure water is said to be neutral, with a pH close to 7.0 at . Solutions with a pH less than 7 are said to be acidic and solutions with a pH greater than 7 are basic or alkaline...
3.5.
Distribution
This species is found from the intertidal zoneIntertidal zone
The intertidal zone is the area that is above water at low tide and under water at high tide . This area can include many different types of habitats, with many types of animals like starfish, sea urchins, and some species of coral...
to depths of up to 3,950 metres. It is found throughout the following areas:
- Antarctica
- Antarctic PeninsulaAntarctic PeninsulaThe Antarctic Peninsula is the northernmost part of the mainland of Antarctica. It extends from a line between Cape Adams and a point on the mainland south of Eklund Islands....
- south Atlantic OceanAtlantic OceanThe Atlantic Ocean is the second-largest of the world's oceanic divisions. With a total area of about , it covers approximately 20% of the Earth's surface and about 26% of its water surface area...
- South Shetland IslandsSouth Shetland IslandsThe South Shetland Islands are a group of Antarctic islands, lying about north of the Antarctic Peninsula, with a total area of . By the Antarctic Treaty of 1959, the Islands' sovereignty is neither recognized nor disputed by the signatories and they are free for use by any signatory for...
(62°00′S 58°00′W) - South Orkney IslandsSouth Orkney IslandsThe South Orkney Islands are a group of islands in the Southern Ocean, about north-east of the tip of the Antarctic Peninsula. They have a total area of about ....
(60°35′S 45°30′W) - South Sandwich Islands (57°45′S 26°30′W)
- South Georgia Island (54°15′S 36°45′W)
- Bouvet IslandBouvet IslandBouvet Island is an uninhabited Antarctic volcanic island in the South Atlantic Ocean, 2,525 km south-southwest of South Africa. It is a dependent territory of Norway and, lying north of 60°S latitude, is not subject to the Antarctic Treaty. The centre of the island is an ice-filled crater of an...
(54°26′S 03°24′E) - Kerguelen Island (49°15′S 69°35′E)
- Cargados Carajos Shoals in the Indian OceanIndian OceanThe Indian Ocean is the third largest of the world's oceanic divisions, covering approximately 20% of the water on the Earth's surface. It is bounded on the north by the Indian Subcontinent and Arabian Peninsula ; on the west by eastern Africa; on the east by Indochina, the Sunda Islands, and...
- Falkland IslandsFalkland IslandsThe Falkland Islands are an archipelago in the South Atlantic Ocean, located about from the coast of mainland South America. The archipelago consists of East Falkland, West Falkland and 776 lesser islands. The capital, Stanley, is on East Falkland...
- Tierra del FuegoTierra del FuegoTierra del Fuego is an archipelago off the southernmost tip of the South American mainland, across the Strait of Magellan. The archipelago consists of a main island Isla Grande de Tierra del Fuego divided between Chile and Argentina with an area of , and a group of smaller islands including Cape...
(54°00′S 70°00′W) - southern ArgentinaArgentinaArgentina , officially the Argentine Republic , is the second largest country in South America by land area, after Brazil. It is constituted as a federation of 23 provinces and an autonomous city, Buenos Aires...
- PeruPeruPeru , officially the Republic of Peru , is a country in western South America. It is bordered on the north by Ecuador and Colombia, on the east by Brazil, on the southeast by Bolivia, on the south by Chile, and on the west by the Pacific Ocean....
- ChileChileChile ,officially the Republic of Chile , is a country in South America occupying a long, narrow coastal strip between the Andes mountains to the east and the Pacific Ocean to the west. It borders Peru to the north, Bolivia to the northeast, Argentina to the east, and the Drake Passage in the far...
Densities range greatly from 0.3 m−2 recorded in McMurdo Sound
McMurdo Sound
The ice-clogged waters of Antarctica's McMurdo Sound extend about 55 km long and wide. The sound opens into the Ross Sea to the north. The Royal Society Range rises from sea level to 13,205 feet on the western shoreline. The nearby McMurdo Ice Shelf scribes McMurdo Sound's southern boundary...
, to the substantially higher densitiy of 26.2 m−2 around Signy Island
Signy Island
Signy Island is a small sub-antarctic island in the South Orkney Islands group locted at . It is about long and wide and rises to above sea level. Much of the island is permanently covered with ice. The average temperature range is to about in winter...
.
Reproduction
This dioeciousDioecious
Dioecy is the property of a group of biological organisms that have males and females, but not members that have organs of both sexes at the same time. I.e., those whose individual members can usually produce only one type of gamete; each individual organism is thus distinctly female or male...
species broadcasts spawn. The resulting pilidium larvae
Larvae
In Roman mythology, lemures were shades or spirits of the restless or malignant dead, and are probably cognate with an extended sense of larvae as disturbing or frightening...
survive in the water column for up to 150 days.
Diet
Parborlasia corrugatus is both a scavengerScavenger
Scavenging is both a carnivorous and herbivorous feeding behavior in which individual scavengers search out dead animal and dead plant biomass on which to feed. The eating of carrion from the same species is referred to as cannibalism. Scavengers play an important role in the ecosystem by...
and a predator, and feeds upon detritus diatoms, gastropods, amphipods, isopods, various vertebrate carrion sponges (including Homaxinella balfourensis), jellyfish
Jellyfish
Jellyfish are free-swimming members of the phylum Cnidaria. Medusa is another word for jellyfish, and refers to any free-swimming jellyfish stages in the phylum Cnidaria...
, seastars, molluscs, anemones, and polychaete worms.
Further reading
- Clarke, A.; Johnston, N.M. (2003). Antarctic marine benthic diversity. Oceanogr. Mar. Biol. Ann. Rev. 41: 47–114
- Biology of the Antarctic Seas XIV, Antarctic Research Series 39(4):289–316, 1983
- Science 245:1484–1486, 1989
- Ecological Monographs 44(1):105–128, 1974
- Journal of Experimental Marine Biology and Ecology 153(1):15–25, 1991
- Antarctic Science 10(4):369–375, 1998
- Polar Biology 25(3):238–240, 2002
- Polar Biology 29(2):106–113, 2006
- Clarke A, Prothero-Thomas E (1997) The influence of feeding on oxygen consumption and nitrogen excretion in the Antarctic nemertean Parborlasia corrugatus. Physiological Zoology, 70, 639–649.
- Gibson R (1983) Antarctic nemerteans: the anatomy, distribution, and biology of Parborlasia corrugatus (McIntosh, 1876) (Heter-onemertea, Lineidae). Biology of the Antarctic seas. XIV. Antarctic Research Series, 39, 289–316.
- Heine JN, McClintock JB, Slattery M, Weston J (1991) Energetic composition, biomass, and chemical defense in the common Antarctic nemertean Parborlasia corrugatus McIntosh. Journal of Experimental Marine Biology and Ecology, 153, 15–25.
- Peck LS (1993) Larval development in the Antarctic nemertean Parbolasia corrugatus (Heteronemertea, Lineidae). Marine Biology, 116, 301–310.
- Rogers AD, Clarke A, Peck LS (1998) Population genetics of the Antarctic heteronemertean Parbolasia corrugatus from the South Orkney Islands. Marine Biology, 131, 1–13.