Mysis
Encyclopedia
Mysis is a genus of mysid crustacean
s in the family Mysidae
, distributed mainly in the coastal zone of the Arctic
and high boreal
seas. There are also several species that inhabit northern freshwater lakes and the brackish Caspian Sea
. Sixteen species are known. Body lengths range from 1 to 3 cm (0.393700787401575 to 1.2 ).
The freshwater taxa of the genus have been referred to as "glacial relict
s", and they comprise four closely related species, most of which also live in brackish water. Mysis relicta
is a freshwater species from boreal lakes of Northern Europe
, also present in the Baltic Sea
. Mysis salemaai is another North European and Baltic Sea taxon. Mysis segerstralei is a fresh- and brackish-water species of the Eurasian and North American Arctic and sub-Arctic. The North American lakes, including the Great Lakes
, are inhabited by Mysis diluviana
.
Four endemic species inhabit the Caspian Sea
. They have specialized and adapted to the cold, deepwater habitats of the landlocked basin. For example, the bathyal M. amblyops, the smallest mysid in the genus, has reduced eyes. Four species also have circum-arctic distributions (M. oculata, M. nordenskioldi, M. segerstralei, M. polaris).
Generic characters: frontal margin of carapace
convex, angular; antennal scale with setae around all margins, segment 2 of maxilla 2 palp large, axe-shaped, with strong serrated spine-setae; pereiopods long, carpopropodus 7–9-segmented; male pleopod 4 5-segmented, segment 4 as long as segment 3; telson
with cleft.
Crustacean
Crustaceans form a very large group of arthropods, usually treated as a subphylum, which includes such familiar animals as crabs, lobsters, crayfish, shrimp, krill and barnacles. The 50,000 described species range in size from Stygotantulus stocki at , to the Japanese spider crab with a leg span...
s in the family Mysidae
Mysidae
Mysidae is a family of crustaceans in the order Mysida or mysid shrimps. Six sub-families are recognised:* Boreomysinae Holt & W. M. Tattersall, 1905a* Siriellinae Norman, 1892* Rhopalophthalminae Hansen, 1910* Gastrosaccinae Norman, 1892...
, distributed mainly in the coastal zone of the Arctic
Arctic
The Arctic is a region located at the northern-most part of the Earth. The Arctic consists of the Arctic Ocean and parts of Canada, Russia, Greenland, the United States, Norway, Sweden, Finland, and Iceland. The Arctic region consists of a vast, ice-covered ocean, surrounded by treeless permafrost...
and high boreal
Boreal
Boreal may refer to*Boreal ecosystem**Boreal climate, the climate found in a region of boreal forests, and designated Dfc, Dwc or Dsc in the Köppen climate classification scheme.*boreal forest*Boreal forest of Canada*Boreal Bluet...
seas. There are also several species that inhabit northern freshwater lakes and the brackish Caspian Sea
Caspian Sea
The Caspian Sea is the largest enclosed body of water on Earth by area, variously classed as the world's largest lake or a full-fledged sea. The sea has a surface area of and a volume of...
. Sixteen species are known. Body lengths range from 1 to 3 cm (0.393700787401575 to 1.2 ).
The freshwater taxa of the genus have been referred to as "glacial relict
Relict
A relict is a surviving remnant of a natural phenomenon.* In biology a relict is an organism that at an earlier time was abundant in a large area but now occurs at only one or a few small areas....
s", and they comprise four closely related species, most of which also live in brackish water. Mysis relicta
Mysis relicta
Mysis relicta is a shrimp-like crustacean in the Mysida order, native to lakes of Northern Europe and to the brackish Baltic Sea.-Appearance:Mysis is a small, transparent shrimp-like crustacean, of less than 2.5 cm length...
is a freshwater species from boreal lakes of Northern Europe
Northern Europe
Northern Europe is the northern part or region of Europe. Northern Europe typically refers to the seven countries in the northern part of the European subcontinent which includes Denmark, Estonia, Latvia, Lithuania, Norway, Finland and Sweden...
, also present in the Baltic Sea
Baltic Sea
The Baltic Sea is a brackish mediterranean sea located in Northern Europe, from 53°N to 66°N latitude and from 20°E to 26°E longitude. It is bounded by the Scandinavian Peninsula, the mainland of Europe, and the Danish islands. It drains into the Kattegat by way of the Øresund, the Great Belt and...
. Mysis salemaai is another North European and Baltic Sea taxon. Mysis segerstralei is a fresh- and brackish-water species of the Eurasian and North American Arctic and sub-Arctic. The North American lakes, including the Great Lakes
Great Lakes
The Great Lakes are a collection of freshwater lakes located in northeastern North America, on the Canada – United States border. Consisting of Lakes Superior, Michigan, Huron, Erie, and Ontario, they form the largest group of freshwater lakes on Earth by total surface, coming in second by volume...
, are inhabited by Mysis diluviana
Mysis diluviana
Mysis diluviana is a mysid crustacean that inhabits freshwater lakes of northern North America.-Appearance:Mysis is a small, transparent shrimp-like crustacean, of less than length...
.
Four endemic species inhabit the Caspian Sea
Caspian Sea
The Caspian Sea is the largest enclosed body of water on Earth by area, variously classed as the world's largest lake or a full-fledged sea. The sea has a surface area of and a volume of...
. They have specialized and adapted to the cold, deepwater habitats of the landlocked basin. For example, the bathyal M. amblyops, the smallest mysid in the genus, has reduced eyes. Four species also have circum-arctic distributions (M. oculata, M. nordenskioldi, M. segerstralei, M. polaris).
Generic characters: frontal margin of carapace
Carapace
A carapace is a dorsal section of the exoskeleton or shell in a number of animal groups, including arthropods such as crustaceans and arachnids, as well as vertebrates such as turtles and tortoises. In turtles and tortoises, the underside is called the plastron.-Crustaceans:In crustaceans, the...
convex, angular; antennal scale with setae around all margins, segment 2 of maxilla 2 palp large, axe-shaped, with strong serrated spine-setae; pereiopods long, carpopropodus 7–9-segmented; male pleopod 4 5-segmented, segment 4 as long as segment 3; telson
Telson
The telson is the last division of the body of a crustacean. It is not considered a true segment because it does not arise in the embryo from teloblast areas as do real segments. It never carries any appendages, but a forked "tail" called the caudal furca is often present. Together with the...
with cleft.
Species
- Mysis amblyops G. O. Sars, 1907
- Mysis arcticoglacialis Petryashev, 1990
- Mysis caspia G. O. Sars, 1895
- Mysis diluvianaMysis diluvianaMysis diluviana is a mysid crustacean that inhabits freshwater lakes of northern North America.-Appearance:Mysis is a small, transparent shrimp-like crustacean, of less than length...
Audzijonyte & Väinölä, 2005 - Mysis gaspensis O. Tattersall, 1954
- Mysis litoralis (Banner, 1948)
- Mysis macrolepis G. O. Sars, 1907
- Mysis microphthalma G. O. Sars, 1895
- Mysis mixta Lilljeborg, 1853
- Mysis nordenskioldi Audzijonyte & Väinölä, 2007
- Mysis oculata (Fabricius, 1780)
- Mysis polaris Holmquist, 1859)
- Mysis relictaMysis relictaMysis relicta is a shrimp-like crustacean in the Mysida order, native to lakes of Northern Europe and to the brackish Baltic Sea.-Appearance:Mysis is a small, transparent shrimp-like crustacean, of less than 2.5 cm length...
Lovén, 1862 - Mysis salemaai Audzijonyte & Väinölä, 2005
- Mysis segerstralei Audzijonyte & Väinölä, 2005
- Mysis stenolepis Smith, 1873