Striped anglerfish ( Antennarius striatus )

The striated frogfish or hairy frogfish (''Antennarius striatus'') is a

marine fish Saltwater fish, also called marine fish or sea fish, are fish that live in seawater. Saltwater fish can swim and live alone or in a large group called a school. Saltwater fish are very commonly kept in aquariums for entertainment. Many saltwater f ...

belonging to 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 ...

Antennariidae.

Description

This small

fish Fish are aquatic, craniate, gill-bearing animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish as well as various extinct related groups. Approximately 95% of ...

grows up to long. Like other members of its family, it has a rounded, extensible body, and its soft skin is covered with irregularly-arranged dermal

spinule Spinules are small spines or thorns (vertebral columns) that are part of biological and manmade structures. The word originates from the Latin word and is often used in botany and zoology. The presence or absence of spinules, and their shape, can ...

s resembling hairs. Its large mouth is forwardly extensible, allowing it to swallow prey as large as itself. The coloring of its body is extremely variable because individual fish tend to match their living environments.

Frogfish 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 fo ...

es have the capacity to change coloration and pigment pattern, taking only a few weeks to adapt. The dominant coloration varies from yellow to brownish-orange, passing through a range of shades, but it can also be green, gray, brown, almost white, or even completely black without any pattern. Body and fins can be marked with roughly parallel dark stripes or elongated blotches, some with rays radiating outward from the eye. The first dorsal spine, the

illicium ''Illicium'' is a genus of flowering plants treated as part of the family Schisandraceae,

, tips forward, and is modified for use like a fishing rod. Its tip has a characteristic worm-like

esca The anglerfish are fish of the teleost order Lophiiformes (). They are bony fish named for their characteristic mode of predation, in which a modified luminescent fin ray (the esca or illicium) acts as a lure for other fish. The luminescence ...

( lure) which, when waved, attracts unsuspecting prey. The dorsal spine is composed of two to seven elongated appendages. The lure is a way to easily distinguish ''A. striatus'' from '' Antennarius hispidus'', which otherwise has similar physical characteristics (stripes, coloration, cutaneous appendages) and with which it is often confused. The illicium has the same length as the second dorsal spine and it is often darkly banded. The second dorsal spine is practically vertical and is movable, while the third one is bent towards the back of the body. They are well separated from each other and also from the

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 ...

. The

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 are angled, and with the pelvic fins, allow the frogfish to "walk" on the sea bottom and to keep a stable position for

ambush An ambush is a long-established military tactic in which a combatant uses an advantage of concealment or the element of surprise to attack unsuspecting enemy combatants from concealed positions, such as among dense underbrush or behind mo ...

Distribution

The striated frogfish is found in the tropical and subtropical waters from 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 t ...

to the center of the

Pacific Ocean The Pacific Ocean is the largest and deepest of Earth's five oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean (or, depending on definition, to Antarctica) in the south, and is bounded by the contin ...

, and in the

Atlantic Ocean 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 ...

on the western coast of

Africa Africa is the world's second-largest and second-most populous continent, after Asia in both cases. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 6% of Earth's total surface area ...

and from the

New Jersey New Jersey is a state in the Mid-Atlantic and Northeastern regions of the United States. It is bordered on the north and east by the state of New York; on the east, southeast, and south by the Atlantic Ocean; on the west by the Delaware ...

coast to the southern

Brazil Brazil ( pt, Brasil; ), officially the Federative Republic of Brazil (Portuguese: ), is the largest country in both South America and Latin America. At and with over 217 million people, Brazil is the world's fifth-largest country by area ...

ian coast including the

Gulf of Mexico The Gulf of Mexico ( es, Golfo de México) is an ocean basin and a marginal sea of the Atlantic Ocean, largely surrounded by the North American continent. It is bounded on the northeast, north and northwest by the Gulf Coast of the United ...

and the Caribbean. The only waters these fish are not found in are the Mediterranean and the Arctic. Williams (1989) and Arnold and Pietsch (2012), however, considered ''Antennarius striatus'' a species complex, and the putative synonym '' Antennarius scaber'' is apparently a distinct species from ''A. striatus'' in having a bifid esca and 11-12 pectoral rays.

Habitat

This

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 ...

inhabits shallow, sandy areas or rocky and coral reefs to deep waters. It can be found from the surface to 210 m with average occurrence at 40 m deep. They often mimic coral or sponges around them to blend in with the environment known as cryptic coloration. As the general daily temperatures continue to rise, this poses a big problem for the oceans and their inhabitants that rely on the ecosystems within to survive. The frogfish is no exception, as they are dependent on coral reefs to blend in and prey on smaller fish. After a frogfish has been subjected to a certain environment, they are able to take in their settings and change color over the span of a few weeks to blend in with the surroundings. With the oceans gradually becoming warmer, this is worsening the pH levels, causing the waters to hold less oxygen and become more acidic. This is greatly expressed in the coral reefs in regard to

coral bleaching Coral bleaching is the process when corals become white due to various stressors, such as changes in temperature, light, or nutrients. Bleaching occurs when coral polyps expel the zooxanthellae ( dinoflagellates that are commonly referred to as a ...

where habitats are being lost daily. The acidic conditions of the oceans bleach the coral, causing it to lose all color. If the coral is losing its color, the frogfish must adapt and overcome or become more vulnerable to predators. This is seen through the species Antennarius maculatus where the frogfish has changed to a white color in order to blend in with the bleached coral in the Indian Ocean

Behaviour

As with all frogfishes, ''A. hispidus'' is a voracious

carnivore A carnivore , or meat-eater (Latin, ''caro'', genitive ''carnis'', meaning meat or "flesh" and ''vorare'' meaning "to devour"), is an animal or plant whose food and energy requirements derive from animal tissues (mainly muscle, fat and other s ...

which will devour all right-sized prey that pass within reach, usually other fish, but sometimes even its own kind. It can swallow prey its own size. Like other members of its family, it has a benthic and solitary lifestyle. They gather during mating period, but do not tolerate each other any more after the act of

fertilization Fertilisation or fertilization (see spelling differences), also known as generative fertilisation, syngamy and impregnation, is the fusion of gametes to give rise to a new individual organism or offspring and initiate its development. Proce ...

. The family Antennariidae use a unique form of locomotion which includes a jet type like propulsion that involves breathing. Water is taken in from the mouth and expelled through tube like gill openings behind the pectoral fins that propel the fish forward by performing opercular exhalations 5. Fish, F. E. (1987). Kinematics and Power Output of Jet Propulsion by the Frogfish Genus Antennarius (Lophiiformes: Antennariidae). The family generally has a globulous body shape with a large mouth upturned in the front of the body. This modification of increased oral cavity and reduced gill openings combined with pulsed water jet like propulsion expelled from breathing allow the fish to propel itself along the floor. They also have a unique jointed pectoral and pelvic fins that allow them to walk along the floor using their anterior dorsal fin in conjunction with their anal tail. Their fins are not modified for actual swimming therefore they remain benthic on the ocean floor. While frogfish have the ability to take in their surroundings and camouflage, they also have the ability to express batesian mimicry where they mimic other dangerous species such as the sea anemone to prevent predators from attacking. An example of such is frogfishes mimicking sea urchins resting on the floor. These fish also have a defense mechanism for when they are found by predators which includes swelling their body with water and remaining inflated to make swallowing difficult. Frogfish are carnivorous, mainly feeding on a diet of small marine fish and crustaceans, but have been known to perform in acts of cannibalism. A. striatus is one of the rare species of this family that exhibits a chemical attractant as well when fishing which is mainly used at night when light is unavailable. It is also observed that the esca is very susceptible to predators therefore the fish rolls it up close to the body when not hunting, and in some species, such as the A. pauciradiatus and A. randalli they have a pocket like structure they can place the esca in between the second and third dorsal spine. Frogfish have one of the fastest eating methods known in the animal kingdom, the fish lacks any teeth and uses suction to inhale its food whole and live. They expand their oral cavity by lowering the lower jaw and extending the upper. The trick remains in gaining the preys attention by moving their illicium usually in an arch like or wiggly fashion to mimic that of a small distressed animal. Once the frogfish can bring their prey close enough, they are able to inhale their prey in six thousandths of a second. File:Antennarius striatus.JPG File:Antennarius striatus2.JPG File:Antennarius striatus3.JPG File:Antennarius striatus C.jpg File:Hairy Frogfish.jpg

References

Other references

* *7. Pietsch, T. W., & Grobecker, D. B. (1990). Science in Pictures: Frogfishes. Scientific American, 262(6), 96-103.

External links

* {{Taxonbar, from=Q1519608 Fish of the Atlantic Ocean Antennariidae Fish described in 1794