''Beroe cucumis'' is a

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

comb jelly Ctenophora (; ctenophore ; ) comprise a phylum of marine invertebrates, commonly known as comb jellies, that inhabit sea waters worldwide. They are notable for the groups of cilia they use for swimming (commonly referred to as "combs"), a ...

in the

family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...

Beroidae. It is found in the Atlantic Ocean. It was first described by the Danish missionary and naturalist

Otto Fabricius Otto Fabricius (6 March 174420 May 1822) was a Danish missionary, naturalist, ethnographer, and explorer of Greenland. Biography Otto Fabricius was born in Rudkøbing on the island of Langeland, Denmark, where his father was a rector. In his ...

in 1780.

Description

''Beroe cucumis'' has a transparent, sac-like body, often somewhat compressed, and reaches a maximum length of about . The wide mouth is at one end. The body has eight longitudinal rows of cilia that extend from the aboral end (opposite end to the mouth), three quarters of the way along the animal. The cilia are arranged on short transverse plates and beat in synchrony to propel the animal through the water, giving a shimmering effect. The general body colour is pink, especially along the rows of cilia, and the plates are bioluminescent. There is a figure of eight shaped ring of small papillae around the aboral tip. Gastrovascular channels extend from the stomach through the body wall beneath the rows of cilia, and these have short side branches, which distinguishes ''Beroe cucumis'' from the otherwise similar ''

Beroe gracilis ''Beroe gracilis'' is a species of comb jelly in the family Beroidae. It is a free-swimming species found in the North Sea, the Atlantic Ocean and the Mediterranean Sea. Description ''Beroe gracilis'' is a translucent, elongated, hollow, cylind ...

''. Juveniles of the two species are indistinguishable.

Distribution

''Beroe cucumis'' is found in the North Atlantic Ocean and the

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

, including the

Skagerrak The Skagerrak (, , ) is a strait running between the Jutland peninsula of Denmark, the southeast coast of Norway and the west coast of Sweden, connecting the North Sea and the Kattegat sea area through the Danish Straits to the Baltic Sea. T ...

and the

Kattegat The Kattegat (; sv, Kattegatt ) is a sea area bounded by the Jutlandic peninsula in the west, the Danish Straits islands of Denmark and the Baltic Sea to the south and the provinces of Bohuslän, Västergötland, Halland and Skåne in Sweden ...

. It sometimes occurs 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 ...

. It is a

pelagic The pelagic zone consists of the water column of the open ocean, and can be further divided into regions by depth (as illustrated on the right). The word ''pelagic'' is derived . The pelagic zone can be thought of as an imaginary cylinder or w ...

, open water species and its depth range is not known.

Ecology

''Beroe cucumis'' is a

predator Predation is a biological interaction where one organism, the predator, kills and eats another organism, its prey. It is one of a family of common feeding behaviours that includes parasitism and micropredation (which usually do not kill th ...

and mostly feeds on other comb jellies, particularly '' Bolinopsis infundibulum''; these are pulled into the large mouth and swallowed whole. The comb jelly ''

Mnemiopsis leidyi ''Mnemiopsis leidyi'', the warty comb jelly or sea walnut, is a species of tentaculate ctenophore (comb jelly). It is native to western Atlantic coastal waters, but has become established as an invasive species in European and western Asian re ...

'' is an invasive species originally native to the western Atlantic coastal waters that was introduced into the

Black Sea The Black Sea is a marginal mediterranean sea of the Atlantic Ocean lying between Europe and Asia, east of the Balkans, south of the East European Plain, west of the Caucasus, and north of Anatolia. It is bounded by Bulgaria, Georgia, Rom ...

in the 1980s, with deleterious results to the ecosystem. Since then it has spread to the

Caspian Sea The Caspian Sea is the world's largest inland body of water, often described as the world's largest lake or a full-fledged sea. An endorheic basin, it lies between Europe and Asia; east of the Caucasus, west of the broad steppe of Central Asia ...

, the

and the

Baltic Sea The Baltic Sea is an arm of the Atlantic Ocean that is enclosed by Denmark, Estonia, Finland, Germany, Latvia, Lithuania, Poland, Russia, Sweden and the North and Central European Plain. The sea stretches from 53°N to 66°N latitude and ...

. In the Black Sea, some measure of control was achieved when another predatory comb jelly, ''

Beroe ovata ''Beroe ovata'' is a comb jelly in the family Beroidae. It is found in the South Atlantic Ocean and the Mediterranean Sea and has been introduced into the Black Sea, the Aegean Sea, the Sea of Azov and the Caspian Sea. It was first described ...

'', was introduced. ''Mnemiopsis leidyi'' was first recorded in the

in 1990 and in 2009, large swarms were present in some areas. ''Beroe cucumis'' is native to the northern Atlantic Ocean and sometimes occurs in the Mediterranean Sea, and it is being monitored to see if it can provide some level of control of ''M. leidyi''. In 2012, ''Beroe cucumis'' was found off the coast of Israel for the first time, and there is proof that it preys on ''M. leidyi'', as an individual was found with a partially digested ''M. leidyi'' in its stomach.

References

{{Taxonbar, from=Q496930 Nuda Fauna of the Atlantic Ocean Fauna of the Mediterranean Sea Animals described in 1780 Taxa named by Otto Fabricius