Solenette
Encyclopedia
The solenette or yellow sole, Buglossidium luteum, is a species
of flatfish
in the family Soleidae
, and the only member
of its genus
. It is characterized by its small size, low-slung semi-circular mouth, and regularly placed dark fin rays. A common and widespread species, it is native to sandy bottoms in the eastern Atlantic Ocean
and the Mediterranean Sea
. It is of little commercial value.
from Iceland
and Scotland
southward, as well as in the North Sea
, Kattegat
and the Baltic Sea
. It also occurs in the Mediterranean Sea
, including the Adriatic Sea
, the Sea of Marmara
, and the Bosphorus. It has been reported from a range of 5-450 m, but is rare in very shallow waters. The highest abundances occur at depths of 5-15 m in the English Channel
and at 20-35 m in the Bay of Biscay
. Their distribution is not restricted by sediment
type as in some other flatfish species. In the Solway Firth
, there is a general movement offshore in the winter.
This species has more specific habitat
requirements than other widespread Atlantic flatfish such as the European plaice
, common sole
, and common dab
. It is concentrated in waters moderately influenced by estuary
outflows, at a salinity
of 29-33 ppt, and is absent from the mouths of the largest estuaries where the salinity is lower. The solenette is often found on or half-buried in muddy or muddy-sandy substrates.
in Europe
an waters, the solenette usually measures 10-13 cm long and attains a maximum length of 15 cm. It has an oval, compressed, slightly elongate body with both eye
s on the right side of the head. The snout
is rounded with the upper jaw slightly elongated to form a "beak
". The diameter of the upper eye is less than the distance between it and the front of the head. The dorsal fin
begins on the anterior profile of the head, with 65-78 fin rays. The anal fin contains 49-63 fin rays, and the caudal fin is connected to the dorsal and anal fins by a small membrane. The pectoral fin on the eyed side is small, with 3-5 fin rays, and the one on the blind side is reduced to 1 long and 1-2 short fin rays.
The lateral line
scale
s number 55-70, and are rectangular in shape with short, strongly curved intercanalicular striae. The coloration of the eyed side is variable, frequently yellowish or light brown with or without darker blotches or spots. The dorsal and anal fins are sandy with every 5th or 6th (occasionally 4th or 7th) fin ray dark for the majority of their lengths. The solenette can change its color to better match its background.
s (copepod
s, amphipods, and cumaceans), bivalve molluscs, and polychaete worms. The diet of the solenette varies by geographical region; solenette from the English Channel feed on a larger variety of prey than those from the Bay of Biscay, and take proportionally more polychaetes as opposed to crustaceans and molluscs for the Bay of Biscay. Feeding activity peaks in summer
and declines markedly in winter
.
The solenette spawns
in February in the Mediterranean, from March to June in the Bay of Biscay, and in July and August in the western English Channel
, North Sea, and western Ireland
. The eggs
are small and distinguishable from those of other soles by having only a few large oil
globules. The larva
e hatch at about 2 mm long, with metamorphosis
beginning at about 7 mm long and being complete at 8-9 mm. In appearance the larvae are similar to those of the common sole, but with fewer large stellate chromatophore
s. There is also a distinct patch of pigment
on the ventral abdominal wall, and the distinct shape of the head is also apparent in the early stages.
In the North Sea, there are no special nursery areas, with juveniles and adults occurring in the same areas. The young take up a benthic lifestyle at 12 mm long. Most growth occurs in the first year of life and continues at a relatively low and constant rate afterwards. Both sexes mature in their third year, with males growing faster than females and females attaining a larger ultimate size. The maximum reported age is 13 years.
s. It is caught as bycatch
in trawls, sometimes in large numbers, and historically has often been confused with the young of the common sole
. Between 1985 and 2006, the range of the solenette increased significantly in the North Sea, which is believed to be a consequence of rising sea bottom temperatures.
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
of flatfish
Flatfish
The flatfish are an order of ray-finned fish, also called the Heterosomata, sometimes classified as a suborder of Perciformes. In many species, both eyes lie on one side of the head, one or the other migrating through and around the head during development...
in the family Soleidae
Soleidae
The true soles are a family, Soleidae, of flatfishes, and include species that live in salt water and fresh water. They are bottom-dwelling fishes feeding on small crustaceans and other invertebrates. Other flatfishes are also known as soles....
, and the only member
Monotypic
In biology, a monotypic taxon is a taxonomic group with only one biological type. The term's usage differs slightly between botany and zoology. The term monotypic has a separate use in conservation biology, monotypic habitat, regarding species habitat conversion eliminating biodiversity and...
of its genus
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
. It is characterized by its small size, low-slung semi-circular mouth, and regularly placed dark fin rays. A common and widespread species, it is native to sandy bottoms in the eastern Atlantic Ocean
Atlantic Ocean
The 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...
and the Mediterranean Sea
Mediterranean Sea
The Mediterranean Sea is a sea connected to the Atlantic Ocean surrounded by the Mediterranean region and almost completely enclosed by land: on the north by Anatolia and Europe, on the south by North Africa, and on the east by the Levant...
. It is of little commercial value.
Distribution and habitat
The solenette occurs in the eastern Atlantic OceanAtlantic Ocean
The 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...
from Iceland
Iceland
Iceland , described as the Republic of Iceland, is a Nordic and European island country in the North Atlantic Ocean, on the Mid-Atlantic Ridge. Iceland also refers to the main island of the country, which contains almost all the population and almost all the land area. The country has a population...
and Scotland
Scotland
Scotland is a country that is part of the United Kingdom. Occupying the northern third of the island of Great Britain, it shares a border with England to the south and is bounded by the North Sea to the east, the Atlantic Ocean to the north and west, and the North Channel and Irish Sea to the...
southward, as well as in the North Sea
North Sea
In the southwest, beyond the Straits of Dover, the North Sea becomes the English Channel connecting to the Atlantic Ocean. In the east, it connects to the Baltic Sea via the Skagerrak and Kattegat, narrow straits that separate Denmark from Norway and Sweden respectively...
, Kattegat
Kattegat
The Kattegat , or Kattegatt is a sea area bounded by the Jutland peninsula and the Straits islands of Denmark on the west and south, and the provinces of Västergötland, Scania, Halland and Bohuslän in Sweden on the east. The Baltic Sea drains into the Kattegat through the Øresund and the Danish...
and 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...
. It also occurs in the Mediterranean Sea
Mediterranean Sea
The Mediterranean Sea is a sea connected to the Atlantic Ocean surrounded by the Mediterranean region and almost completely enclosed by land: on the north by Anatolia and Europe, on the south by North Africa, and on the east by the Levant...
, including the Adriatic Sea
Adriatic Sea
The Adriatic Sea is a body of water separating the Italian Peninsula from the Balkan peninsula, and the system of the Apennine Mountains from that of the Dinaric Alps and adjacent ranges...
, the Sea of Marmara
Sea of Marmara
The Sea of Marmara , also known as the Sea of Marmora or the Marmara Sea, and in the context of classical antiquity as the Propontis , is the inland sea that connects the Black Sea to the Aegean Sea, thus separating Turkey's Asian and European parts. The Bosphorus strait connects it to the Black...
, and the Bosphorus. It has been reported from a range of 5-450 m, but is rare in very shallow waters. The highest abundances occur at depths of 5-15 m in the English Channel
English Channel
The English Channel , often referred to simply as the Channel, is an arm of the Atlantic Ocean that separates southern England from northern France, and joins the North Sea to the Atlantic. It is about long and varies in width from at its widest to in the Strait of Dover...
and at 20-35 m in the Bay of Biscay
Bay of Biscay
The Bay of Biscay is a gulf of the northeast Atlantic Ocean located south of the Celtic Sea. It lies along the western coast of France from Brest south to the Spanish border, and the northern coast of Spain west to Cape Ortegal, and is named in English after the province of Biscay, in the Spanish...
. Their distribution is not restricted by sediment
Sediment
Sediment is naturally occurring material that is broken down by processes of weathering and erosion, and is subsequently transported by the action of fluids such as wind, water, or ice, and/or by the force of gravity acting on the particle itself....
type as in some other flatfish species. In the Solway Firth
Solway Firth
The Solway Firth is a firth that forms part of the border between England and Scotland, between Cumbria and Dumfries and Galloway. It stretches from St Bees Head, just south of Whitehaven in Cumbria, to the Mull of Galloway, on the western end of Dumfries and Galloway. The Isle of Man is also very...
, there is a general movement offshore in the winter.
This species has more specific habitat
Habitat
* Habitat , a place where a species lives and grows*Human habitat, a place where humans live, work or play** Space habitat, a space station intended as a permanent settlement...
requirements than other widespread Atlantic flatfish such as the European plaice
European plaice
The European plaice, Pleuronectes platessa, is a commercially important flatfish.- Distribution and habitat :The geographical range of the European plaice is off all coasts from the Barents Sea to the Mediterranean, also in the Northeast Atlantic and along Greenland...
, common sole
Common sole
The common sole, Dover sole, or black sole, Solea solea, is a species of flatfish in the Soleidae family.It has a preference for relatively shallow water with sand or mud covering the bottom....
, and common dab
Common dab
The common dab, Limanda limanda, is an edible flatfish of the family Pleuronectidae. It is a demersal fish native to shallow seas around Northern Europe, in particular the North Sea, where it lives on sandy bottoms down to depths of about...
. It is concentrated in waters moderately influenced by estuary
Estuary
An estuary is a partly enclosed coastal body of water with one or more rivers or streams flowing into it, and with a free connection to the open sea....
outflows, at a salinity
Salinity
Salinity is the saltiness or dissolved salt content of a body of water. It is a general term used to describe the levels of different salts such as sodium chloride, magnesium and calcium sulfates, and bicarbonates...
of 29-33 ppt, and is absent from the mouths of the largest estuaries where the salinity is lower. The solenette is often found on or half-buried in muddy or muddy-sandy substrates.
Description
The smallest of the solesSole (fish)
Sole is a group of flatfish belonging to several families. Generally speaking, they are members of the family Soleidae, but, outside Europe, the name sole is also applied to various other similar flatfish, especially other members of the sole suborder Soleoidei as well as members of the flounder...
in Europe
Europe
Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...
an waters, the solenette usually measures 10-13 cm long and attains a maximum length of 15 cm. It has an oval, compressed, slightly elongate body with both eye
Eye
Eyes are organs that detect light and convert it into electro-chemical impulses in neurons. The simplest photoreceptors in conscious vision connect light to movement...
s on the right side of the head. The snout
Snout
The snout, or muzzle, is the protruding portion of an animal's face, consisting of its nose, mouth, and jaw.-Terminology:The term "muzzle", used as a noun, can be ambiguous...
is rounded with the upper jaw slightly elongated to form a "beak
Beak
The beak, bill or rostrum is an external anatomical structure of birds which is used for eating and for grooming, manipulating objects, killing prey, fighting, probing for food, courtship and feeding young...
". The diameter of the upper eye is less than the distance between it and the front of the head. The dorsal fin
Dorsal fin
A dorsal fin is a fin located on the backs of various unrelated marine and freshwater vertebrates, including most fishes, marine mammals , and the ichthyosaurs...
begins on the anterior profile of the head, with 65-78 fin rays. The anal fin contains 49-63 fin rays, and the caudal fin is connected to the dorsal and anal fins by a small membrane. The pectoral fin on the eyed side is small, with 3-5 fin rays, and the one on the blind side is reduced to 1 long and 1-2 short fin rays.
The lateral line
Lateral line
The lateral line is a sense organ in aquatic organisms , used to detect movement and vibration in the surrounding water. Lateral lines are usually visible as faint lines running lengthwise down each side, from the vicinity of the gill covers to the base of the tail...
scale
Scale (zoology)
In most biological nomenclature, a scale is a small rigid plate that grows out of an animal's skin to provide protection. In lepidopteran species, scales are plates on the surface of the insect wing, and provide coloration...
s number 55-70, and are rectangular in shape with short, strongly curved intercanalicular striae. The coloration of the eyed side is variable, frequently yellowish or light brown with or without darker blotches or spots. The dorsal and anal fins are sandy with every 5th or 6th (occasionally 4th or 7th) fin ray dark for the majority of their lengths. The solenette can change its color to better match its background.
Biology and ecology
Adult solenette feed on a variety of small benthic organisms, mainly crustaceanCrustacean
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 (copepod
Copepod
Copepods are a group of small crustaceans found in the sea and nearly every freshwater habitat. Some species are planktonic , some are benthic , and some continental species may live in limno-terrestrial habitats and other wet terrestrial places, such as swamps, under leaf fall in wet forests,...
s, amphipods, and cumaceans), bivalve molluscs, and polychaete worms. The diet of the solenette varies by geographical region; solenette from the English Channel feed on a larger variety of prey than those from the Bay of Biscay, and take proportionally more polychaetes as opposed to crustaceans and molluscs for the Bay of Biscay. Feeding activity peaks in summer
Summer
Summer is the warmest of the four temperate seasons, between spring and autumn. At the summer solstice, the days are longest and the nights are shortest, with day-length decreasing as the season progresses after the solstice...
and declines markedly in winter
Winter
Winter is the coldest season of the year in temperate climates, between autumn and spring. At the winter solstice, the days are shortest and the nights are longest, with days lengthening as the season progresses after the solstice.-Meteorology:...
.
The solenette spawns
Spawn (biology)
Spawn refers to the eggs and sperm released or deposited, usually into water, by aquatic animals. As a verb, spawn refers to the process of releasing the eggs and sperm, also called spawning...
in February in the Mediterranean, from March to June in the Bay of Biscay, and in July and August in the western English Channel
English Channel
The English Channel , often referred to simply as the Channel, is an arm of the Atlantic Ocean that separates southern England from northern France, and joins the North Sea to the Atlantic. It is about long and varies in width from at its widest to in the Strait of Dover...
, North Sea, and western Ireland
Ireland
Ireland is an island to the northwest of continental Europe. It is the third-largest island in Europe and the twentieth-largest island on Earth...
. The eggs
Egg (biology)
An egg is an organic vessel in which an embryo first begins to develop. In most birds, reptiles, insects, molluscs, fish, and monotremes, an egg is the zygote, resulting from fertilization of the ovum, which is expelled from the body and permitted to develop outside the body until the developing...
are small and distinguishable from those of other soles by having only a few large oil
Oil
An oil is any substance that is liquid at ambient temperatures and does not mix with water but may mix with other oils and organic solvents. This general definition includes vegetable oils, volatile essential oils, petrochemical oils, and synthetic oils....
globules. The larva
Larva
A larva is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle...
e hatch at about 2 mm long, with metamorphosis
Metamorphosis
Metamorphosis is a biological process by which an animal physically develops after birth or hatching, involving a conspicuous and relatively abrupt change in the animal's body structure through cell growth and differentiation...
beginning at about 7 mm long and being complete at 8-9 mm. In appearance the larvae are similar to those of the common sole, but with fewer large stellate chromatophore
Chromatophore
Chromatophores are pigment-containing and light-reflecting cells found in amphibians, fish, reptiles, crustaceans, and cephalopods. They are largely responsible for generating skin and eye colour in cold-blooded animals and are generated in the neural crest during embryonic development...
s. There is also a distinct patch of pigment
Pigment
A pigment is a material that changes the color of reflected or transmitted light as the result of wavelength-selective absorption. This physical process differs from fluorescence, phosphorescence, and other forms of luminescence, in which a material emits light.Many materials selectively absorb...
on the ventral abdominal wall, and the distinct shape of the head is also apparent in the early stages.
In the North Sea, there are no special nursery areas, with juveniles and adults occurring in the same areas. The young take up a benthic lifestyle at 12 mm long. Most growth occurs in the first year of life and continues at a relatively low and constant rate afterwards. Both sexes mature in their third year, with males growing faster than females and females attaining a larger ultimate size. The maximum reported age is 13 years.
Relationship to humans
The solenette is too small to be of commercial interest and is usually discarded by fisherFishing
Fishing is the activity of trying to catch wild fish. Fish are normally caught in the wild. Techniques for catching fish include hand gathering, spearing, netting, angling and trapping....
s. It is caught as bycatch
Bycatch
The term “bycatch” is usually used for fish caught unintentionally in a fishery while intending to catch other fish. It may however also indicate untargeted catch in other forms of animal harvesting or collecting...
in trawls, sometimes in large numbers, and historically has often been confused with the young of the common sole
Common sole
The common sole, Dover sole, or black sole, Solea solea, is a species of flatfish in the Soleidae family.It has a preference for relatively shallow water with sand or mud covering the bottom....
. Between 1985 and 2006, the range of the solenette increased significantly in the North Sea, which is believed to be a consequence of rising sea bottom temperatures.