| Euchaetidae | |
|---|---|
 | |
| Euchaeta marina | |
Scientific classification  | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Arthropoda |
| Subphylum: | Crustacea |
| Class: | Copepoda |
| Order: | Calanoida |
| Family: | Euchaetidae Giesbrecht, 1893 |
| Genera | |
| |
Euchaetidae is a family of marine copepods. [1] The family is cosmopolitan and occurs in all the oceans, including the Southern and Arctic Oceans. [2] [3] Euchaetidae are medium to large-sized copepods. [4]
There are two genera with in total 114 species: [1]
Euchaeta are mostly epipelagic whereas Paraeuchaeta are mostly bathypelagic. [2] Where more than one species occurs, congeneric species (or life stages of a single species, as observed for Paraeuchaeta antarctica) may partition the water column, whereas species representing different genera that occur at similar depths differ in dietary preferences. [3]
Paraeuchaeta can be important predators of fish larvae. Their mode of predation is "drift and wait". The dominant euchaetid in the Southern Ocean is Paraeuchaeta antarctica. It is a dominant predator there, and its fatty acid profile suggests that it mostly preys upon herbivorous calanid copepods. In the Weddell Sea, it contributes as much as 11–18% to total mesozooplankton biomass. [3]
Paraeuchaeta antarctica has a one-year life-cycle around the Kerguelen Islands. [3]
Antarctic krill is a species of krill found in the Antarctic waters of the Southern Ocean. It is a small, swimming crustacean that lives in large schools, called swarms, sometimes reaching densities of 10,000–30,000 individual animals per cubic metre. It feeds directly on minute phytoplankton, thereby using the primary production energy that the phytoplankton originally derived from the sun in order to sustain their pelagic life cycle. It grows to a length of 6 centimetres (2.4 in), weighs up to 2 grams (0.071 oz), and can live for up to six years. It is a key species in the Antarctic ecosystem and in terms of biomass, is one of the most abundant animal species on the planet – approximately 500 million metric tons.
Krill are small and exclusively marine crustaceans of the order Euphausiacea, found in all the world's oceans. The name "krill" comes from the Norwegian word krill, meaning "small fry of fish", which is also often attributed to species of fish.
Nototheniidae, the notothens or cod icefishes, is a family of ray-finned fishes, part of the suborder Notothenioidei which is traditionally placed within the order Perciformes. They are largely found in the Southern Ocean.
The capelin or caplin is a small forage fish of the smelt family found in the North Atlantic, North Pacific and Arctic oceans. In summer, it grazes on dense swarms of plankton at the edge of the ice shelf. Larger capelin also eat a great deal of krill and other crustaceans. Among others, whales, seals, Atlantic cod, Atlantic mackerel, squid and seabirds prey on capelin, in particular during the spawning season while the capelin migrate south. Capelin spawn on sand and gravel bottoms or sandy beaches at the age of two to six years. When spawning on beaches, capelin have an extremely high post-spawning mortality rate which, for males, is close to 100%. Males reach 20 cm (8 in) in length, while females are up to 25.2 cm (10 in) long. They are olive-coloured dorsally, shading to silver on sides. Males have a translucent ridge on both sides of their bodies. The ventral aspects of the males iridesce reddish at the time of spawn.
The Antarctic fur seal, is one of eight seals in the genus Arctocephalus, and one of nine fur seals in the subfamily Arctocephalinae. Despite what its name suggests, the Antarctic fur seal is mostly distributed in Subantarctic islands and its scientific name is thought to have come from the German vessel SMS Gazelle, which was the first to collect specimens of this species from Kerguelen Islands.
Calanoida is an order of copepods, a group of arthropods commonly found as zooplankton. The order includes around 46 families with about 1800 species of both marine and freshwater copepods between them.
The Antarctic silverfish, or Antarctic herring, is a species of marine ray-finned fish belonging to the family Nototheniidae, the notothens or cod icefishes. It is native to the Southern Ocean and the only truly pelagic fish in the waters near Antarctica. It is a keystone species in the ecosystem of the Southern Ocean.
Limacina helicina is a species of small swimming planktonic sea snail in the family Limacinidae, which belong to the group commonly known as sea butterflies (Thecosomata).
Limacina rangii is a species of swimming sea snail in the family Limacinidae, which belong to the group commonly known as sea butterflies (Thecosomata).
The Antarctic scallop is a species of bivalve mollusc in the large family of scallops, the Pectinidae. It was thought to be the only species in the genus Adamussium until an extinct Pliocene species was described in 2016. Its exact relationship to other members of the Pectinidae is unclear. It is found in the ice-cold seas surrounding Antarctica, sometimes at great depths.
The wildlife of Antarctica are extremophiles, having adapted to the dryness, low temperatures, and high exposure common in Antarctica. The extreme weather of the interior contrasts to the relatively mild conditions on the Antarctic Peninsula and the subantarctic islands, which have warmer temperatures and more liquid water. Much of the ocean around the mainland is covered by sea ice. The oceans themselves are a more stable environment for life, both in the water column and on the seabed.
The Antarctic lanternfish or Electrona antarctica mainly inhabits the Antarctic deep, warm waters. It is the dominant species in the Southern Ocean. Their life span is about 4–5 years and they mature after 2–3 years. Their maximum length is 12.5 cm. Their feeding depends upon area to area. Small fish primarily feed on copepods, euphausiid larvae, and hyperiids. This species is mainly the nektonic prey species of seabirds in open water. It is an important krill predator and serves as prey for a majority of seabirds. It is one of the southernmost fish species, being recorded as far south as 74°40′S in the Ross Sea.
Temperature change due to climate change in Antarctica is not stable over the whole continent. West Antarctica is warming rapidly, while the inland regions are cooled by the winds in Antarctica. Water in the West Antarctic has warmed by 1 °C since year 1955. Further increase in temperature in water and on land will affect the climate, ice mass and life on the continent and have global implications. Present-day greenhouse gas concentrations are higher than ever according to ice cores from Antarctica, which indicates that warming on this continent is not part of a natural cycle and attributable to anthropogenic climate change.
Acartia tonsa is a species of marine copepod in the family Acartiidae.
Calanus propinquus is a copepod found in Antarctica, and the surrounding waters.
Pseudocalanus newmani is a copepod found in Arctic and northern Pacific waters. It was described by Frost in 1989. It is found in the Arctic and surrounding waters. There are multiple generations. Unlike some copepods, P. newmani undergoes reverse diel vertical migration, descending during the night, and ascending during the day, although it may undergo normal or no migration at all depending on predation. This copepod is primarily herbivorous.
Metridia gerlachei is a copepod found primarily in Antarctic and sub-Antarctic waters.
Pseudocalanus minutus is a small copepod found in the Arctic Ocean and surrounding waters.
Anasterias antarctica, commonly called the Cinderella starfish, is a species of starfish in the family Asteriidae. It is found in coastal waters in the Southern Ocean and around Antarctica.
Tritoniella is a genus of sea slugs, specifically dendronotid nudibranchs. It is a marine gastropod mollusc in the family Tritoniidae.The genus was described in 1907 by the British diplomat and malacologist Charles Eliot.