''Zeugopterus punctatus'', the common topknot, is a species of left eyed

flatfish A flatfish is a member of the Ray-finned fish, ray-finned demersal fish Order (biology), suborder Pleuronectoidei, also called the Heterosomata. In many species, both eyes lie on one side of the head, one or the other migrating through or around ...

in the family

Scophthalmidae The Scophthalmidae are a family (biology), family of flatfish found in the North Atlantic Ocean, Baltic Sea, Mediterranean Sea, and Black Sea. Fish of this family are known commonly as turbots, though this name can refer specifically to ''Scophth ...

, from the eastern Atlantic Ocean.

Description

''Zeugopterus punctatus'' is a small left-sided flatfish that is almost completely round in shape, with a broad body relative to its length. It is a mottled brown and white colour, a dark bar through the eyes, light wide fins all the way round its body and a very small tail. Unlike most other flatfish, ''Zeugopterus punctatus'' does not seem to change colour for

camouflage Camouflage is the use of any combination of materials, coloration, or illumination for concealment, either by making animals or objects hard to see, or by disguising them as something else. Examples include the leopard's spotted coat, the b ...

but relies on immobility to avoid detection. ''Zeugopterus punctatus'' grows to a maximum length of about . It is sometimes confused with the

lemon sole The lemon sole (''Microstomus kitt'') is a flatfish of the family Pleuronectidae. It is native to shallow seas around Northern Europe, where it lives on stony bottoms down to depths of about . It grows up to in length and reaches about in weigh ...

''Microstomus kitti'' which can be found on rocky substrates too but has a noticeable pattern on its back, does not have such long fins and is a more pointed shape. The eyed side is covered in small ctenoid scales while the blind side has

cycloid In geometry, a cycloid is the curve traced by a point on a circle as it Rolling, rolls along a Line (geometry), straight line without slipping. A cycloid is a specific form of trochoid and is an example of a roulette (curve), roulette, a curve g ...

scales, the many small ctenoid scales feel downy to the touch.

Distribution

The eastern

Atlantic Ocean The Atlantic Ocean is the second largest of the world's five borders of the oceans, oceanic divisions, with an area of about . It covers approximately 17% of Earth#Surface, Earth's surface and about 24% of its water surface area. During the ...

including the

North Sea The North Sea lies between Great Britain, Denmark, Norway, Germany, the Netherlands, Belgium, and France. A sea on the European continental shelf, it connects to the Atlantic Ocean through the English Channel in the south and the Norwegian Se ...

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 ...

English Channel The English Channel, also known as the Channel, is an arm of the Atlantic Ocean that separates Southern England from northern France. It links to the southern part of the North Sea by the Strait of Dover at its northeastern end. It is the busi ...

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 Point Penmarc'h to the Spanish border, and along the northern coast of Spain, extending westward ...

south to the coast of

Portugal Portugal, officially the Portuguese Republic, is a country on the Iberian Peninsula in Southwestern Europe. Featuring Cabo da Roca, the westernmost point in continental Europe, Portugal borders Spain to its north and east, with which it share ...

Biology

This species lives along coastlines. It is unusual among European flatfish in that it prefers a rocky substrate. It has the ability to remain immobile in the most surprising sites, holding on to vertical rocks or even upside down under overhangs. This is achieved by using its broad fringing fins to fit itself into the substrate. Spawning takes place between February and June. It is carnivorous, feeding on small fish and crustaceans.

References

{{Taxonbar, from=Q2161231 Fish of Europe Scophthalmidae Fish described in 1787