HOME

TheInfoList



OR:

Frogfishes are any member of the anglerfish family Antennariidae, of the order Lophiiformes. Antennariids are known as anglerfish in Australia, where the term "frogfish" refers to members of the unrelated family Batrachoididae. Frogfishes are found in almost all tropical and subtropical oceans and seas around the world, the primary exception being the Mediterranean Sea. Frogfishes are small, short and stocky, and sometimes covered in spinules and other appendages to aid in camouflage. The camouflage aids in protection from predators and enables them to lure prey. Many species can change colour; some are covered with other organisms such as
algae Algae ( , ; : alga ) are any of a large and diverse group of photosynthetic, eukaryotic organisms. The name is an informal term for a polyphyletic grouping that includes species from multiple distinct clades. Included organisms range from ...
or hydrozoa. In keeping with this camouflage, frogfishes typically move slowly, lying in wait for prey, and then striking extremely rapidly, in as little as 6 milliseconds. Few traces of frogfishes remain in the fossil record, though ''Antennarius monodi'' is known from the
Miocene The Miocene ( ) is the first geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and means "less recent" ...
of Algeria and ''Eophryne barbuttii'' is known from the
Eocene The Eocene ( ) Epoch is a geological epoch that lasted from about 56 to 33.9 million years ago (mya). It is the second epoch of the Paleogene Period in the modern Cenozoic Era. The name ''Eocene'' comes from the Ancient Greek (''ēṓs'', " ...
of Italy.


Range

Frogfishes live in the
tropical The tropics are the regions of Earth surrounding the Equator. They are defined in latitude by the Tropic of Cancer in the Northern Hemisphere at N and the Tropic of Capricorn in the Southern Hemisphere at S. The tropics are also referred to ...
and subtropical regions of the
Atlantic The Atlantic Ocean is the second-largest of the world's five oceans, with an area of about . It covers approximately 20% of Earth's surface and about 29% of its water surface area. It is known to separate the "Old World" of Africa, Europe an ...
and Pacific, as well as in the
Indian Ocean The Indian Ocean is the third-largest of the world's five oceanic divisions, covering or ~19.8% of the water on Earth's surface. It is bounded by Asia to the north, Africa to the west and Australia to the east. To the south it is bounded by ...
and the
Red Sea The Red Sea ( ar, البحر الأحمر - بحر القلزم, translit=Modern: al-Baḥr al-ʾAḥmar, Medieval: Baḥr al-Qulzum; or ; Coptic: ⲫⲓⲟⲙ ⲛ̀ϩⲁϩ ''Phiom Enhah'' or ⲫⲓⲟⲙ ⲛ̀ϣⲁⲣⲓ ''Phiom ǹšari''; ...
. Their habitat lies for the most part between the 20 °C isotherms, in areas where the surface level water usually has a temperature of or more. They extend beyond the 20 °C isotherms in the area of the
Azores ) , motto= ( en, "Rather die free than subjected in peace") , anthem=( en, "Anthem of the Azores") , image_map=Locator_map_of_Azores_in_EU.svg , map_alt=Location of the Azores within the European Union , map_caption=Location of the Azores wi ...
,
Madeira ) , anthem = ( en, "Anthem of the Autonomous Region of Madeira") , song_type = Regional anthem , image_map=EU-Portugal_with_Madeira_circled.svg , map_alt=Location of Madeira , map_caption=Location of Madeira , subdivision_type=Sovereign st ...
and the
Canary Islands The Canary Islands (; es, Canarias, ), also known informally as the Canaries, are a Spanish autonomous community and archipelago in the Atlantic Ocean, in Macaronesia. At their closest point to the African mainland, they are west of Mo ...
, along the Atlantic coast of the United States, on the south coast of Australia and the northern tip of New Zealand, coastal Japan, around
Durban Durban ( ) ( zu, eThekwini, from meaning 'the port' also called zu, eZibubulungwini for the mountain range that terminates in the area), nicknamed ''Durbs'',Ishani ChettyCity nicknames in SA and across the worldArticle on ''news24.com'' from ...
,
South Africa South Africa, officially the Republic of South Africa (RSA), is the southernmost country in Africa. It is bounded to the south by of coastline that stretch along the South Atlantic and Indian Oceans; to the north by the neighbouring count ...
, and at
Baja California Baja California (; 'Lower California'), officially the Free and Sovereign State of Baja California ( es, Estado Libre y Soberano de Baja California), is a state in Mexico. It is the northernmost and westernmost of the 32 federal entities of Mex ...
, Mexico.''Antennariidae: Frogfishes''
Tree of Life Web Project
The greatest diversity of species is in the
Indo-Pacific The Indo-Pacific is a vast biogeographic region of Earth. In a narrow sense, sometimes known as the Indo-West Pacific or Indo-Pacific Asia, it comprises the tropical waters of the Indian Ocean, the western and central Pacific Ocean, and the ...
region, with the highest concentration around
Indonesia Indonesia, officially the Republic of Indonesia, is a country in Southeast Asia and Oceania between the Indian and Pacific oceans. It consists of over 17,000 islands, including Sumatra, Java, Sulawesi, and parts of Borneo and New Guine ...
. In the small Lembeh Strait, north-east of Sulawesi, divers have found 9 different species. Frogfish live generally on the ocean floor around
coral Corals are marine invertebrates within the class Anthozoa of the phylum Cnidaria. They typically form compact colonies of many identical individual polyps. Coral species include the important reef builders that inhabit tropical oceans and secre ...
or rock reefs, at most to deep. A few exceptions to these general limits are known. The brackishwater frogfish is at home in ocean waters as well as
brackish Brackish water, sometimes termed brack water, is water occurring in a natural environment that has more salinity than freshwater, but not as much as seawater. It may result from mixing seawater (salt water) and fresh water together, as in estuari ...
and fresh water around
river mouth A river mouth is where a river flows into a larger body of water, such as another river, a lake/reservoir, a bay/ gulf, a sea, or an ocean. At the river mouth, sediments are often deposited due to the slowing of the current reducing the carryin ...
s. The sargassum fish lives in clumps of drifting sargassum, which often floats into the deeper ocean and has been known to take the sargassum fish as far north as Norway.


Features

Frogfishes have a stocky appearance, atypical of fish. Ranging from long, their plump, high-backed, unstreamlined body is scaleless and bare, often covered with bumpy, bifurcated spinules. Their short bodies have between 18 and 23
vertebrae The spinal column, a defining synapomorphy shared by nearly all vertebrates, Hagfish are believed to have secondarily lost their spinal column is a moderately flexible series of vertebrae (singular vertebra), each constituting a characteristi ...
and their mouths are upward-pointed with palatal teeth. They are often brightly coloured, white, yellow, red, green, or black or spotted in several colours to blend in with their coral surroundings. Coloration can also vary within one species, making it difficult to differentiate between them. Rather than typical
dorsal fin A dorsal fin is a fin located on the back of most marine and freshwater vertebrates within various taxa of the animal kingdom. Many species of animals possessing dorsal fins are not particularly closely related to each other, though through c ...
s, the front-most of the three fins is called the illicium or "rod" and is topped with the esca or "lure". The illicium often has striped markings, while the esca takes a different form in each species. Because of the variety of colours even within a single species, the esca and illicium are useful tools to differentiate among different varieties.Diving with Frogfish
Dive the World 2009
Some of them resemble fish, some
shrimp Shrimp are crustaceans (a form of shellfish) with elongated bodies and a primarily swimming mode of locomotion – most commonly Caridea and Dendrobranchiata of the decapod order, although some crustaceans outside of this order are refer ...
, some
polychaete Polychaeta () is a paraphyletic class of generally marine annelid worms, commonly called bristle worms or polychaetes (). Each body segment has a pair of fleshy protrusions called parapodia that bear many bristles, called chaetae, which are ...
s, some
tubeworm A tubeworm is any worm-like sessile invertebrate that anchors its tail to an underwater surface and secretes around its body a mineral tube, into which it can withdraw its entire body. Tubeworms are found among the following taxa: * Annelida, the ...
s, and some simply a formless lump; one genus, ''
Echinophryne ''Echinophryne'' is a small genus of frogfishes. Species There are currently three recognized species in this genus: * '' Echinophryne crassispina'' McCulloch & Waite, 1918 (Prickly anglerfish) * '' Echinophryne mitchellii'' Morton, 1897 ( ...
'', has no esca at all. Despite very specific mimicry in the esca, examinations of stomach contents do not reveal any specialized predation patterns, for example, only worm-eating fish consumed by frogfishes with worm-mimicking esca. If lost, the esca can be regenerated. In many species, the illicium and esca can be withdrawn into a depression between the second and third dorsal fins for protection when they are not needed.''Frogfish Factsheet''
Shedd Aquarium Explore by Animal 2009
Frogfish have small, round gill openings behind their
pectoral fin Fins are distinctive anatomical features composed of bony spines or rays protruding from the body of a fish. They are covered with skin and joined together either in a webbed fashion, as seen in most bony fish, or similar to a flipper, as ...
s. With the exception of Butler's frogfish and the rough anglerfish, frogfish use a gas bladder to control their buoyancy.


Mimicry and camouflage

The unusual appearance of the frogfish functions to conceal it from predators and sometimes to mimic a potential meal to its prey. In the study of animal behavior, this is known as aggressive mimicry. Their unusual shape, colour, and skin textures disguise frogfish. Some resemble stones or coral, while others imitate
sponge Sponges, the members of the phylum Porifera (; meaning 'pore bearer'), are a basal animal clade as a sister of the diploblasts. They are multicellular organisms that have bodies full of pores and channels allowing water to circulate throug ...
s or sea squirts with dark splotches instead of holes. In 2005, a species was discovered, the
striated frogfish The striated frogfish or hairy frogfish (''Antennarius striatus'') is a marine fish belonging to the family Antennariidae. Description This small fish grows up to long. Like other members of its family, it has a rounded, extensible body, ...
, that mimics a
sea urchin Sea urchins () are spiny, globular echinoderms in the class Echinoidea. About 950 species of sea urchin live on the seabed of every ocean and inhabit every depth zone from the intertidal seashore down to . The spherical, hard shells (tests) ...
, while the
sargassumfish The sargassum fish, anglerfish, or frog fish (''Histrio histrio'') is a frogfish of the family Antennariidae, the only species in its genus. It lives among '' Sargassum'' seaweed which floats in subtropical oceans. The scientific name comes ...
is coloured to blend in with the surrounding sargassum. Some frogfish are covered with
algae Algae ( , ; : alga ) are any of a large and diverse group of photosynthetic, eukaryotic organisms. The name is an informal term for a polyphyletic grouping that includes species from multiple distinct clades. Included organisms range from ...
or hydrozoa. Their
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 ...
can be so perfect that sea slugs have been known to crawl over the fish without recognizing them. For the scaleless and unprotected frogfish, camouflage is an important defense against predators. Some species can also inflate themselves, like pufferfish, by sucking in water in a threat display. In aquaria and in nature, frogfish have been observed, when flushed from their hiding spots and clearly visible, to be attacked by clownfish, damselfish, and wrasses, and in aquaria, to be killed. Many frogfishes can change their colour. The light colours are generally yellows or yellow-browns, while the darker are green, black, or dark red. They usually appear with the lighter color, but the change can last from a few days to several weeks. What triggers the change is unknown.


Movement

Frogfishes generally do not move very much, preferring to lie on the sea floor and wait for prey to approach. Once the prey is spotted, they can approach slowly using their pectoral and pelvic fins to walk along the floor. They rarely swim, preferring to clamber over the sea bottom with their fins in one of two "gaits". In the first, they alternately move their pectoral fins forward, propelling themselves somewhat like a two-legged
tetrapod Tetrapods (; ) are four-limb (anatomy), limbed vertebrate animals constituting the superclass Tetrapoda (). It includes extant taxon, extant and extinct amphibians, sauropsids (reptiles, including dinosaurs and therefore birds) and synapsids (p ...
, leaving the pelvic fins out. Alternately, they can move in something like a slow gallop, whereby they move their pectoral fins simultaneously forward and back, transferring their weight to the pelvic fins while moving the pectorals forward. With either gait, they can cover only short stretches. In open water, frogfishes can swim with strokes of the caudal fin. They also use jet propulsion, often used by younger frogfish. It is achieved by rhythmically gulping water and forcing it out through their gill openings, also called opercular openings, which lie behind their pectoral fins. The sargassum frogfish has adapted fins which can grab strands of sargassum, enabling it to "climb" through the seaweed.


Hunting

Frogfishes eat
crustacean Crustaceans (Crustacea, ) form a large, diverse arthropod taxon which includes such animals as decapods, seed shrimp, branchiopods, fish lice, krill, remipedes, isopods, barnacles, copepods, amphipods and mantis shrimp. The crustacean gro ...
s, other fish, and even each other. When potential prey is first spotted, the frogfish follows it with its eyes. Then, when it approaches within roughly seven body-lengths, the frogfish begins to move its illicium in such a way that the esca mimics the motions of the animal it resembles. As the prey approaches, the frogfish slowly moves to prepare for its attack; sometimes this involves approaching the prey or "stalking", while sometimes it is simply adjusting its mouth angle. The catch itself is made by the sudden opening of the jaws, which enlarges the volume of the mouth cavity up to 12-fold, pulling the prey into the mouth along with water. The attack can be as fast as 6
milliseconds A millisecond (from '' milli-'' and second; symbol: ms) is a unit of time in the International System of Units (SI) equal to one thousandth (0.001 or 10−3 or 1/1000) of a second and to 1000 microseconds. A unit of 10 milliseconds may be ca ...
. The water flows out through the gills, while the prey is swallowed and the esophagus closed with a special muscle to keep the victim from escaping. In addition to expanding their mouths, frogfish can also expand their stomachs to swallow animals up to twice their size. Slow-motion filming has shown that the frogfish sucks in its prey in just six milliseconds, so fast that other animals cannot see it happen.


Reproduction

The reproductive behavior of the normally solitary frogfish is still not fully researched. Few observations in aquaria and even fewer from the wild have been made. Most species are free-spawning, with females laying the eggs in the water and males coming in behind to fertilize them. From eight hours to several days before the egg-laying, the abdomen of the female starts to swell as up to 180,000 eggs absorb water. The male begins to approach the female around two days before the spawning. Whether the spawn is predetermined by some external factor, such as the phase of the moon, or if the male is attracted to a smell or signal released by the female, is unknown. In all hitherto observed breeding pairs, one partner was noticeably larger than the other, sometimes as much as 10 times. When the gender could be determined, the larger partner was always the female. During the free-spawning courtship ritual, the male swims beside and somewhat behind the female, nudges her with his mouth, then remains near her cloaca. Just before the spawning, the female begins to swim above the ocean floor toward the surface. At the highest point of their swim, they release the eggs and sperm before descending. Sometimes, the male pulls the eggs out of the female with his mouth. After mating, the partners depart quickly as otherwise the smaller male would likely be eaten. A few species are substrate-spawners, notably the
genera Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial ...
'' Lophiocharon'', '' Phyllophryne'', and '' Rhycherus'', which lay their eggs on a solid surface, such as a plant or rock. Some species guard their eggs, a duty assigned to the male in almost all species, while most others do not. Several species practice brood carrying, for example the three-spot frogfish, whose eggs are attached to the male, and those in the genus '' Histiophryne'', whose brood are carried in the pectoral fins. The eggs are in diameter and cohere in a gelatinous mass or long ribbon, which in sargassumfish are up to a metre (3.3 ft) long and wide. These egg masses can include up to 180,000 eggs. For most species, the eggs drift on the surface. After two to five days, the fish hatch and the newly hatched alevin are between long. For the first few days, they live on the yolk sac while their digestive systems continue to develop. The young have long fin filaments and can resemble tiny, tentacled
jellyfish Jellyfish and sea jellies are the informal common names given to the medusa-phase of certain gelatinous members of the subphylum Medusozoa, a major part of the phylum Cnidaria. Jellyfish are mainly free-swimming marine animals with umbrella- ...
. For one to two months, they live
plankton Plankton are the diverse collection of organisms found in water (or air) that are unable to propel themselves against a current (or wind). The individual organisms constituting plankton are called plankters. In the ocean, they provide a cr ...
ically. After this stage, at a length between , they have the form of adult frogfish and begin their lives on the sea floor. Young frogfish often mimic the coloration of poisonous
sea slug Sea slug is a common name for some marine invertebrates with varying levels of resemblance to terrestrial slugs. Most creatures known as sea slugs are gastropods, i.e. they are sea snails (marine gastropod mollusks) that over evolutionary ...
s or
flatworm The flatworms, flat worms, Platyhelminthes, or platyhelminths (from the Greek πλατύ, ''platy'', meaning "flat" and ἕλμινς (root: ἑλμινθ-), ''helminth-'', meaning "worm") are a phylum of relatively simple bilaterian, unsegme ...
s.


Fossil record

Very few fossil remains of frogfishes have been found. In the northern Italian formation at Monte Bolca, formed from the sedimentation of the Tethys Ocean in the middle
Eocene The Eocene ( ) Epoch is a geological epoch that lasted from about 56 to 33.9 million years ago (mya). It is the second epoch of the Paleogene Period in the modern Cenozoic Era. The name ''Eocene'' comes from the Ancient Greek (''ēṓs'', " ...
(45 million years ago), a 3-cm (1.2 in) fossil named ''Histionotophorus bassani'' was initially described as a frogfish, but was later thought to belong to the closely related extant genus ''Brachionichthys'' or handfish. In 2005, a fossil from
Miocene The Miocene ( ) is the first geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and means "less recent" ...
Algeria (3 to 23 million years ago), ''Antennarius monodi'', is the first proven fossil frogfish, believed to be most closely related to the extant Senegalese frogfish. In 2009, a new fossil from the upper Ypresian Stage of the early
Eocene The Eocene ( ) Epoch is a geological epoch that lasted from about 56 to 33.9 million years ago (mya). It is the second epoch of the Paleogene Period in the modern Cenozoic Era. The name ''Eocene'' comes from the Ancient Greek (''ēṓs'', " ...
found in Monte Bolca, Italy was described as a new species, ''Eophryne barbuttii'', and is the oldest known member of the family. G. Carnevalel & T.W. Pietsch. 2009. An Eocene frogfish from Monte Bolca, Italy: The earliest known skeletal record for the family


Taxonomy

Frogfishes belong to the order Lophiiformes, commonly known as anglerfish, which is a member of the superorder Paracanthopterygii with four other orders. They belong to the
infraclass In biological classification, class ( la, classis) is a taxonomic rank, as well as a taxonomic unit, a taxon, in that rank. It is a group of related taxonomic orders. Other well-known ranks in descending order of size are life, domain, king ...
Teleostei, the bony fishes, in the class Actinopterygii. There are two subfamilies, Antennariinae and Histiophryninae, which differ in their distribution and reproductive method. File:Commerson's Frogfish, Kona, Hawaii.jpg, Commerson's frogfish,
Kona Kona or KONA may refer to: People *Kona (surname) * Dilshad Nahar Kona, Bangladeshi singer also known as Kona Television * ''Kona'' (TV series), a Kenyan telenovela that premiered in 2013 Locations * Kona, Kentucky * Kona, North Carolina * Kon ...
, Hawaii, ''Antennarius commerson'' File:Oscellated Frogfish.jpg, Ocellated frogfish,
Bonaire Bonaire (; , ; pap, Boneiru, , almost pronounced ) is a Dutch island in the Leeward Antilles in the Caribbean Sea. Its capital is the port of Kralendijk, on the west (leeward) coast of the island. Aruba, Bonaire and Curaçao form the ABC ...
, Netherlands Antilles, ''A. ocellatus'' File:Red oscellated frogfish.jpg, Red ocellated frogfish,
St. Kitts Saint Kitts, officially the Saint Christopher Island, is an island in the West Indies. The west side of the island borders the Caribbean Sea, and the eastern coast faces the Atlantic Ocean. Saint Kitts and the neighbouring island of Nevis cons ...
, F''. ocellatus'' File:6903 aquaimages.jpg, Longlure frogfish, Bonaire, ''A. multiocellatus'' File:Scarlet frogfish-Antennarius coccineus BK.jpg,
Scarlet frogfish ''Antennatus coccineus'', the scarlet or freckled frogfish, is a species of frogfish originally classified as ''Chironectes coccineus'' and ''Antennarius coccineus''. It lives within tropical waters and has a central distribution being around In ...
, ''A. coccineus'' File:Antennarius pictus.JPG, Painted frogfish, ''A. pictus'' File:Clown frogfish.jpg,
Warty frogfish The warty frogfish or clown frogfish (''Antennarius maculatus'') is a marine fish belonging to the family Antennariidae. Description The warty frogfish grows up to long. Like other members of its family, it has a globulous, extensible body, a ...
, ''A. maculatus''


References


External links


Tree of Life - Antennariidae

Frogfishes in Fishbase

Website only about Frogfishes (Anglerfishes)
{{Authority control Antennariidae Taxa named by Theodore Gill