The Atlantic stargazer (''Uranoscopus scaber'') is a

marine Marine is an adjective meaning of or pertaining to the sea or ocean. Marine or marines may refer to: Ocean * Maritime (disambiguation) * Marine art * Marine biology * Marine debris * Marine habitats * Marine life * Marine pollution Military * ...

, subtropical fish of family Uranoscopidae. Its body is suited for living on the sea floor, and is one of few fish capable of

bioelectrogenesis Electroreception and electrogenesis are the closely-related biological abilities to perceive electrical stimuli and to generate electric fields. Both are used to locate prey; stronger electric discharges are used in a few groups of fishes to stu ...

, or the ability to generate an electric charge.

Distribution and habitat

It is widespread along the Atlantic coast of Europe and Africa, is very common in the Mediterranean and Black Sea, and somewhat rare in the

Bay of Biscay The Bay of Biscay (), known in Spain as the Gulf of Biscay ( es, Golfo de Vizcaya, eu, Bizkaiko Golkoa), and in France and some border regions as the Gulf of Gascony (french: Golfe de Gascogne, oc, Golf de Gasconha, br, Pleg-mor Gwaskogn), ...

. It is a

demersal fish Demersal fish, also known as groundfish, live and feed on or near the bottom of seas or lakes (the demersal zone).Walrond Carl . "Coastal fish - Fish of the open sea floor"Te Ara - the Encyclopedia of New Zealand. Updated 2 March 2009 They occ ...

, which lives in sandy or muddy sand sediments along the upper slope of the continental shelf, between depths of 14–400 meters. It is not an economically important fish, primarily caught as by-catch, but is ecologically important.

Description

Typical of

stargazer Stargazer may refer to: * an observational astronomer, particularly an amateur Aerospace * Stargazer (aircraft), a Lockheed L-1011 airliner used to launch the Pegasus rocket * Orbiting Astronomical Observatory 2, nicknamed Stargazer, the first s ...

s, its body is somewhat dorso-ventrally flattened, lacks a swimbladder, and has been found as large as 35.0 centimeters in length, but is usually between 20 and 30 cm. Its head and jaws are rotated upward, and has very large eyes and mouth. Its body is brown in color and can have numerous small light spots, with a lighter belly. It lives to about 5 or 6 years, and females are larger in size than males.

Biology

Feeding

Like other stargazers, it is an ambush predator which lies buried under sand with only its eyes showing. It has a large mouth, with a small strip of skin protruding from its lower jaw, which it moves in and out rapidly to act as a lure for prey. When a prey item comes near, the fish lunges toward the prey using a specially adapted vertebral column to generate the force by bending 60°, which takes less than 30 milliseconds to engulf the prey. It feeds primarily on fish larvae and smaller fishes, such as gobies, picarels, and small crustaceans, but has also been known to eat molluscs,

echinoderms An echinoderm () is any member of the phylum Echinodermata (). The adults are recognisable by their (usually five-point) radial symmetry, and include starfish, brittle stars, sea urchins, sand dollars, and sea cucumbers, as well as the sea li ...

, annelids,

algae Algae (; singular alga ) is an informal term for a large and diverse group of photosynthetic eukaryotic organisms. It is a polyphyletic grouping that includes species from multiple distinct clades. Included organisms range from unicellular mic ...

and plant material.

Reproduction

They can spawn between April and September, depending on the region, and produce pelagic eggs, about 2 millimeters in diameter. After hatching, the larvae, post-larvae, and juveniles remain pelagic. Males are slightly more common than females, but this can vary within local populations.

Electric organ

All species within the genus '' Uranoscopus'', along with those in ''

Astroscopus ''Astroscopus'', the electric stargazers, is a genus of stargazers, a type of percomorph fish from the family Uranoscopidae, part of the order Trachiniformes. The species in this genus are anatomically distinct Uranoscopids, being characterize ...

'', have evolved electric organs, but lack receptor organs. These were both independently evolved, and are the only two genera within the order Perciformes to produce electric organ discharges (EODs). The Atlantic stargazer, like other

bioelectrogenic Electroreception and electrogenesis are the closely-related biological abilities to perceive electrical stimuli and to generate electric fields. Both are used to locate prey; stronger electric discharges are used in a few groups of fishes to stu ...

stargazers, produces pulse-type EODs while feeding and when it is disturbed. The Atlantic stargazer produces EODs with the electric organ, derived from sonic muscles. In other fishes, sonic muscles are used to produce sound by agitating the swim bladder.

References

{{Taxonbar, from=Q744000

Atlantic stargazer The Atlantic stargazer (''Uranoscopus scaber'') is a Marine (ocean), marine, subtropical fish of family Uranoscopidae. Its body is suited for living on the sea floor, and is one of few fish capable of bioelectrogenic, bioelectrogenesis, or the ab ...

Fish of Western Asia Marine fauna of West Africa Marine fish of Europe Fish of the East Atlantic Fish of the Mediterranean Sea Fish of the Black Sea Fish of the North Sea

Taxa named by Carl Linnaeus