The corkwing wrasse (''Symphodus melops'') is a species of

wrasse The wrasses are a family, Labridae, of marine fish, many of which are brightly colored. The family is large and diverse, with over 600 species in 81 genera, which are divided into 9 subgroups or tribes. They are typically small, most of them le ...

native to the eastern

Atlantic Ocean The Atlantic Ocean is the second-largest of the world's five oceans, with an area of about . It covers approximately 20% of Earth's surface and about 29% of its water surface area. It is known to separate the " Old World" of Africa, Europe ...

from

Norway Norway, officially the Kingdom of Norway, is a Nordic country in Northern Europe, the mainland territory of which comprises the western and northernmost portion of the Scandinavian Peninsula. The remote Arctic island of Jan Mayen and t ...

Morocco Morocco (),, ) officially the Kingdom of Morocco, is the westernmost country in the Maghreb region of North Africa. It overlooks the Mediterranean Sea to the north and the Atlantic Ocean to the west, and has land borders with Algeria to ...

and out to the

Azores ) , motto =( en, "Rather die free than subjected in peace") , anthem= ( en, "Anthem of the Azores") , image_map=Locator_map_of_Azores_in_EU.svg , map_alt=Location of the Azores within the European Union , map_caption=Location of the Azores wi ...

, as well as being found in the

Mediterranean Sea The Mediterranean Sea is a sea connected to the Atlantic Ocean, surrounded by the Mediterranean Basin and almost completely enclosed by land: on the north by Western and Southern Europe and Anatolia, on the south by North Africa, and on the ea ...

and the

Adriatic Sea The Adriatic Sea () is a body of water separating the Italian Peninsula from the Balkan Peninsula. The Adriatic is the northernmost arm of the Mediterranean Sea, extending from the Strait of Otranto (where it connects to the Ionian Sea) to t ...

. This species can be found in areas of rock or eelgrass at depths from .

Description

Skärsnultra - (Symphodus melops) - Wilhelm von Wright

Its body is deep and compressed sideways, with a single, long

dorsal fin A dorsal fin is a fin located on the back of most marine and freshwater vertebrates within various taxa of the animal kingdom. Many species of animals possessing dorsal fins are not particularly closely related to each other, though through conv ...

. It is usually about long, but has reached . It is highly variable in colour, depending on the environment and age of the fish. The corkwing wrasse has a black spot in the middle of the tail stalk, and a comma-shaped spot behind the eye. Females and juveniles tend to be brown or greenish-brown, while the males are typically more brightly coloured. Both sexes have lines on their heads and gill covers which are brown and pale blue in the female, and bright green or blue in the male. It feeds on a large variety of prey, but mainly bivalves and copepods.

Reproduction

The males exhibit dimorphism, where the territorial males build a ball-shaped nest of seaweed in rock crevices or sedimentary areas, amongst

seaweed Seaweed, or macroalgae, refers to thousands of species of macroscopic, multicellular, marine algae. The term includes some types of '' Rhodophyta'' (red), ''Phaeophyta'' (brown) and ''Chlorophyta'' (green) macroalgae. Seaweed species such as ...

seagrass Seagrasses are the only flowering plants which grow in marine environments. There are about 60 species of fully marine seagrasses which belong to four families (Posidoniaceae, Zosteraceae, Hydrocharitaceae and Cymodoceaceae), all in the orde ...

es. The nest has an entrance hole which the male guards aggressively. The other morph mimics the females and tries to sneak-fertilize. The sneakers are much smaller than the territorial males, and cannot be visually distinguished from females. As there is a trade-off between reproductive investment and growth, the sneakers have much larger gonads related to body size than the territorial males. Their sperm quality is also shown to be better for the sneaker, as it is longer-lived. About 5 – 20% of the males in a population tend to be sneakers.

Importance

The fish has been commercially used since 1988 because of its ability to remove parasites from other fish. It is today heavily fished and one may say exploited for the use in aquaculture to remove salmon louse (''Lepeophtheirus salmonis'').

References

* Deady, S., Varian, S. J. A. and Fives, J. M. (1995) The use of cleaner-fish to control sea lice on two Irish salmon (Salmo salar) farms with particular reference to wrasse behaviour in salmon cages. ''Aquaculture.'' 131: 73-90. * Potts, G.W. (1973) Cleaning symbiosis among British fish with special reference to Crenilabrus melops (Labridae). ''J. mar. biol. asso. UK.'' 53: 1-10. * Potts, G.W. (1985) The nest structure of the corkwing wrasse, Crenilabrus melops (Labridae: Teleostei). ''J. mar. biol. ass. UK''. 65: 531-546. * Sayer, M. D. J., Gibson, R. N. and Atkinson, R. J. A. (1996) Growth, diet and condition of the corkwing wrasse and rock cook on the west coast of Scotland. ''J. Fish. Biol''. 49(1): 76-94. * Uglem, I., Rosenqvist, G. and Wasslavik, H. S. (2000) Phenotypic variation between dimorphic males in corkwing wrasse. ''J. Fish. Biol.'' 57: 1-14. * Uglem, I., Mayer, I. and Rosenqvist, G. (2002) Variation in Plasma Steroids and Reproductive Traits in Dimorphic Males of Corkwing Wrasse (Symphodus melops L.). ''Hormones and behavior''. 41(4): 396-404. * Uglem, I. & Rosenqvist, G. (2002) Nest Building and Mating in Relation to Male Size in Corkwing Wrasse, Symphodus Melops. Environmental ''Biology of Fishes''. 63(1): 17-25.

External links

* {{Taxonbar, from=Q1417448

corkwing wrasse The corkwing wrasse (''Symphodus melops'') is a species of wrasse native to the eastern Atlantic Ocean from Norway to Morocco and out to the Azores, as well as being found in the Mediterranean Sea and the Adriatic Sea. This species can be found ...

Fauna of the Azores Fish of the North Sea

Taxa named by Carl Linnaeus