''Palaemon adspersus'', commonly called Baltic prawn, is a

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

shrimp A shrimp (: shrimp (American English, US) or shrimps (British English, UK)) is a crustacean with an elongated body and a primarily Aquatic locomotion, swimming mode of locomotion – typically Decapods belonging to the Caridea or Dendrobranchi ...

that is frequent in the

Baltic Sea The Baltic Sea is an arm of the Atlantic Ocean that is enclosed by the countries of Denmark, Estonia, Finland, Germany, Latvia, Lithuania, Poland, Russia, Sweden, and the North European Plain, North and Central European Plain regions. It is the ...

, and is the subject of

fisheries Fishery can mean either the enterprise of raising or harvesting fish and other aquatic life or, more commonly, the site where such enterprise takes place ( a.k.a., fishing grounds). Commercial fisheries include wild fisheries and fish farm ...

Denmark Denmark is a Nordic countries, Nordic country in Northern Europe. It is the metropole and most populous constituent of the Kingdom of Denmark,, . also known as the Danish Realm, a constitutionally unitary state that includes the Autonomous a ...

. It is up to long, and lives in ''

Zostera ''Zostera'' is a small genus of widely distributed seagrasses, commonly called marine eelgrass, or simply seagrass or eelgrass. The genus ''Zostera'' contains 15 species. Ecology '' Zostera marina'' is found on sandy substrates or in estuarie ...

'' beds.

Description

''Palaemon adspersus'' is up to long, with a plain yellowish-grey body. The

rostrum Rostrum may refer to: * Any kind of a platform for a speaker: **dais **pulpit ** podium * Rostrum (anatomy), a beak, or anatomical structure resembling a beak, as in the mouthparts of many sucking insects * Rostrum (ship), a form of bow on naval ...

bears distinctive spots of pigment on its lower half.

Distribution and ecology

Peeling cooked baltic prawns Dragstrup Vig 2009-08-04

''Palaemon adspersus'' is uncommon over most of north-western Europe, but forms the basis of a significant

fishery Fishery can mean either the enterprise of raising or harvesting fish and other aquatic life or, more commonly, the site where such enterprise takes place ( a.k.a., fishing grounds). Commercial fisheries include wild fisheries and fish far ...

in the

Danish straits The Danish straits are the straits connecting the Baltic Sea to the North Sea through the Kattegat and Skagerrak. Historically, the Danish straits were internal waterways of Denmark; however, following territorial losses, Øresund and Fehmarn B ...

. In the

, it can tolerate

salinities Salinity () is the saltiness or amount of salt dissolved in a body of water, called saline water (see also soil salinity). It is usually measured in g/L or g/kg (grams of salt per liter/kilogram of water; the latter is dimensionless and equal to ...

as low as 5

‰ The phrase per mille () indicates parts per thousand. The associated symbol is , similar to a per cent sign but with an extra zero in the divisor. Major dictionaries do not agree on the spelling, giving other options of per mil, per mill, pe ...

, but it

overwinters Overwintering is the process by which some organisms pass through or wait out the winter season, or pass through that period of the year when "winter" conditions (cold or sub-zero temperatures, ice, snow, limited food supplies) make normal activi ...

in deeper, more saline waters offshore. In

, ''P. adspersus'' is closely associated with ''

'' (eelgrass) beds, and is replaced by ''

Palaemon elegans ''Palaemon elegans'' sometimes known by the common name rockpool shrimp, is a species of shrimp of the family Palaemonidae. It is native to the eastern North Atlantic (including Macaronesia), the Baltic, the Mediterranean and the Black Sea, and i ...

'' where the eelgrass is lacking.

Taxonomic history

Carl Linnaeus Carl Linnaeus (23 May 1707 – 10 January 1778), also known after ennoblement in 1761 as Carl von Linné,#Blunt, Blunt (2004), p. 171. was a Swedish biologist and physician who formalised binomial nomenclature, the modern system of naming o ...

described this species under the name ''Cancer squilla'' in his ''

Systema Naturae ' (originally in Latin written ' with the Orthographic ligature, ligature æ) is one of the major works of the Sweden, Swedish botanist, zoologist and physician Carl Linnaeus (1707–1778) and introduced the Linnaean taxonomy. Although the syste ...

'' (1758, 1761). As more genera were split from Linnaeus' ''Cancer'', this species became known as ''Leander squilla'', while the genus '' Palaemon'' was used for other species. In 1897, Mary Jane Rathbun realised that a

type species In International_Code_of_Zoological_Nomenclature, zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the spe ...

for the genus ''Palaemon'' had been made in 1810 by

Pierre André Latreille Pierre André Latreille (; 29 November 1762 – 6 February 1833) was a French zoology, zoologist, specialising in arthropods. Having trained as a Roman Catholic priest before the French Revolution, Latreille was imprisoned, and only regained hi ...

, and that the chosen species was ''Cancer squilla''. This required the genus then known as ''Leander'' to become ''Palaemon'', while the genus then known as ''Palaemon'' had to become ''

Macrobrachium ''Macrobrachium'' is a genus of freshwater prawns or shrimps characterised by the extreme enlargement of the second pair of pereiopods, at least in the male. Species It contains these species: *'' Macrobrachium acanthochirus'' F. Villalobos, ...

''. Not all biologists followed the new nomenclature, and the confusion was eventually resolved by a ruling from the

International Commission on Zoological Nomenclature The International Commission on Zoological Nomenclature (ICZN) is an organization dedicated to "achieving stability and sense in the scientific naming of animals". Founded in 1895, it currently comprises 26 commissioners from 20 countries. Orga ...

(ICZN), which stated that the type species of ''Palaemon'' would be ''Palaemon adspersus''. In 1958,

Lipke Holthuis Lipke Bijdeley Holthuis (21 April 1921 – 7 March 2008) was a Dutch carcinologist, considered one of the "undisputed greats" of carcinology, and "the greatest carcinologist of our time". Holthuis was born in Probolinggo, East Java and obtained ...

petitioned the ICZN to suppress the Linnaean name ''Cancer squilla'' because it had come to be used for the species ''

'' even though the original description was of a different species. Despite opposition from some carcinologists, including

Robert Gurney Robert Gurney (31 July 1879 – 5 March 1950) was a British zoologist from the Gurney family, most famous for his monographs on ''British Freshwater Copepoda'' (1931–1933) and the ''Larvae of Decapod Crustacea'' (1942). He was not affiliated ...

, the ICZN concurred, leaving ''Palaemon adspersus'' Rathke, 1837 the oldest available name for the species.

References

{{Portal bar, Crustaceans, Marine life Palaemonidae Caridea of the Atlantic Ocean Crustaceans described in 1837