The angler, also sometimes called fishing-frog, frog-fish or sea-devil, Lophius piscatorius, is a monkfish

Monkfish

Monkfish is the English name of a number of types of fish in the northwest Atlantic, most notably the species of the anglerfish genus Lophius and the angelshark genus Squatina...

 in the family Lophiidae. It is found in coastal waters of the northeast Atlantic, from the Barents Sea

Barents Sea

The Barents Sea is a marginal sea of the Arctic Ocean, located north of Norway and Russia. Known in the Middle Ages as the Murman Sea, the sea takes its current name from the Dutch navigator Willem Barents...

 to the Strait of Gibraltar

Strait of Gibraltar

The Strait of Gibraltar is a narrow strait that connects the Atlantic Ocean to the Mediterranean Sea and separates Spain in Europe from Morocco in Africa. The name comes from Gibraltar, which in turn originates from the Arabic Jebel Tariq , albeit the Arab name for the Strait is Bab el-Zakat or...

, the Mediterranean and the Black Sea

Black Sea

The Black Sea is bounded by Europe, Anatolia and the Caucasus and is ultimately connected to the Atlantic Ocean via the Mediterranean and the Aegean seas and various straits. The Bosphorus strait connects it to the Sea of Marmara, and the strait of the Dardanelles connects that sea to the Aegean...

. Within some of its range, including the Irish Sea

Irish Sea

The Irish Sea separates the islands of Ireland and Great Britain. It is connected to the Celtic Sea in the south by St George's Channel, and to the Atlantic Ocean in the north by the North Channel. Anglesey is the largest island within the Irish Sea, followed by the Isle of Man...

 this species comprises a significant commercial fishery.

External anatomy

It has a very large head which is broad, flat and depressed; the rest of the body appears to be a mere appendage. The wide mouth extends all the way around the anterior circumference of the head, and both jaws are armed with bands of long pointed teeth. These are inclined inwards, and can be closed so as to offer no impediment to an object gliding towards the stomach, but to prevent its escape from the mouth.

The pectoral and pelvic fins are so articulated as to perform the functions of feet, so that the fish is able to walk along the bottom of the sea, where it generally hides itself in the sand

Sand

Sand is a naturally occurring granular material composed of finely divided rock and mineral particles.The composition of sand is highly variable, depending on the local rock sources and conditions, but the most common constituent of sand in inland continental settings and non-tropical coastal...

 or amongst seaweed

Seaweed

Seaweed is a loose, colloquial term encompassing macroscopic, multicellular, benthic marine algae. The term includes some members of the red, brown and green algae...

. All round its head and also along the body the skin bears fringed appendages resembling short fronds of seaweed, a structure which, combined with the extraordinary faculty of assimilating the colour of the body to its surroundings, assists this fish greatly in camouflaging

Camouflage

Camouflage is a method of concealment that allows an otherwise visible animal, military vehicle, or other object to remain unnoticed, by blending with its environment. Examples include a leopard's spotted coat, the battledress of a modern soldier and a leaf-mimic butterfly...

 itself in the places which it selects on account of the abundance of prey. It has no scales

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...

, thereby is not kosher.

Female anglers grow to a length of more than 2 m.

Angling

The fish also has eighty long filaments along the middle of its head, which are, in fact, the detached and modified three first spines of the anterior 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...

. The filament most important to the angler is the first, which is the longest, terminates in a lappet

Lappet

A lappet is a decorative flap or fold in a ceremonial headdress or garment. They were a feature of women's headgear until the early 20th century. They remain strongly associated with religion. A bishop's mitre has two lappets sewn to the back of it. The most famous usage of lappets occurs on the...

, and is movable in every direction. The angler is believed to attract other fishes by means of its lure, and then to seize them with its enormous jaws. It is probable enough that smaller fish are attracted in this way, but experiments have shown that the action of the jaws is automatic and depends on contact of the prey with the tentacle. Its stomach is expandable and it is not unknown for these fish to swallow prey of its own size.

Lifecycle

The spawn

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...

 of the angler consists of a thin sheet of transparent gelatinous material 2 or 3 feet broad (60–90 cm) and 25 to 30 feet (8 or 9 metres) in length drifting freely in the water. The eggs in this sheet are in a single layer, each in its own little cavity. 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 are free-swimming and have the pelvic fins elongated into filaments.

Sustainable consumption

In 2010, Greenpeace

Greenpeace

Greenpeace is a non-governmental environmental organization with offices in over forty countries and with an international coordinating body in Amsterdam, The Netherlands...

 International added the angler to its seafood

Seafood

Seafood is any form of marine life regarded as food by humans. Seafoods include fish, molluscs , crustaceans , echinoderms . Edible sea plants, such as some seaweeds and microalgae, are also seafood, and are widely eaten around the world, especially in Asia...

red list, a list of commonly sold fish which have a very high risk of being sourced from unsustainable fisheries.