Goby
Overview
The gobies form the family
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...

 Gobiidae, which is one of the largest families of fish
Fish
Fish are a paraphyletic group of organisms that consist of all gill-bearing aquatic vertebrate 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...

, with more than 2,000 species
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...

 in more than 200 genera
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...

. Most are relatively small, typically less than 10 cm (4 in) in length. Gobies include some of the smallest vertebrates in the world, like species of the genera Trimmatom nanus
Trimmatom nanus
Trimmatom nanus is a species of marine fish in family Gobiidae of Perciformes. It is the type species of its genus. One of the fishes called dwarf gobies, it is native to the Chagos Archipelago and the Maldives in the western Indian Ocean....

and Pandaka pygmaea
Pandaka pygmaea
The dwarf pygmy goby is a tropical freshwater fish of the family Gobiidae. It is one of the smallest fish in the world by mass, and is also one of the shortest freshwater fish. Mature males can reach up to 1.1 cm, while the females can grow up to 1.5 cm. Average weight is from 4 to 5 mg...

, which are under 1 cm (3/8 in) long when fully grown. There are some large gobies, such as some species of the genera Gobioides or Periophthalmodon, that can reach over 30 cm (1 ft) in length, but that is exceptional.
Unanswered Questions
Encyclopedia
The gobies form the family
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...

 Gobiidae, which is one of the largest families of fish
Fish
Fish are a paraphyletic group of organisms that consist of all gill-bearing aquatic vertebrate 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...

, with more than 2,000 species
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...

 in more than 200 genera
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...

. Most are relatively small, typically less than 10 cm (4 in) in length. Gobies include some of the smallest vertebrates in the world, like species of the genera Trimmatom nanus
Trimmatom nanus
Trimmatom nanus is a species of marine fish in family Gobiidae of Perciformes. It is the type species of its genus. One of the fishes called dwarf gobies, it is native to the Chagos Archipelago and the Maldives in the western Indian Ocean....

and Pandaka pygmaea
Pandaka pygmaea
The dwarf pygmy goby is a tropical freshwater fish of the family Gobiidae. It is one of the smallest fish in the world by mass, and is also one of the shortest freshwater fish. Mature males can reach up to 1.1 cm, while the females can grow up to 1.5 cm. Average weight is from 4 to 5 mg...

, which are under 1 cm (3/8 in) long when fully grown. There are some large gobies, such as some species of the genera Gobioides or Periophthalmodon, that can reach over 30 cm (1 ft) in length, but that is exceptional. Although few are important as food for humans, they are of great significance as prey species for commercially important fish like cod
Cod
Cod is the common name for genus Gadus, belonging to the family Gadidae, and is also used in the common name for various other fishes. Cod is a popular food with a mild flavor, low fat content and a dense, flaky white flesh. Cod livers are processed to make cod liver oil, an important source of...

, haddock
Haddock
The haddock , also known as the offshore hake, is a marine fish distributed on both sides of the North Atlantic. Haddock is a popular food fish and is widely fished commercially....

, sea bass
Barramundi
The Barramundi , also known as Asian Seabass, is a species of catadromous fish in family Latidae of order Perciformes. The native species is widely distributed in the Indo-West Pacific region from the Persian Gulf, through Southeast Asia to Papua New Guinea and Northern Australia. Known in Thai...

, and flatfish
Flatfish
The flatfish are an order of ray-finned fish, also called the Heterosomata, sometimes classified as a suborder of Perciformes. In many species, both eyes lie on one side of the head, one or the other migrating through and around the head during development...

. Several gobies are also of interest as aquarium fish, such as the bumblebee gobies of the genus Brachygobius
Brachygobius
Brachygobius is a small genus of gobies. They are popular aquarium fish where a number of species are sold as bumblebee gobies because their colours are similar to those of bumblebees.-Morphology:...

.

The most distinctive aspects of goby morphology are the fused pelvic fins that form a disc-shaped sucker. This sucker is functionally analogous to the 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...

 sucker possessed by the remora
Remora
The remora , sometimes called a suckerfish or sharksucker, is an elongated, brown fish in the order Perciformes and family Echeneidae...

s or the pelvic fin sucker of the lumpsucker
Lumpsucker
Lumpsuckers or lumpfish are mostly small scorpaeniform marine fish of the family Cyclopteridae. They are found in the cold waters of the Arctic, North Atlantic, and North Pacific oceans...

s, but is anatomically distinct: these similarities are the product of convergent evolution
Convergent evolution
Convergent evolution describes the acquisition of the same biological trait in unrelated lineages.The wing is a classic example of convergent evolution in action. Although their last common ancestor did not have wings, both birds and bats do, and are capable of powered flight. The wings are...

. Gobies can often be seen using the sucker to adhere to rocks and coral
Coral
Corals are marine animals in class Anthozoa of phylum Cnidaria typically living in compact colonies of many identical individual "polyps". The group includes the important reef builders that inhabit tropical oceans and secrete calcium carbonate to form a hard skeleton.A coral "head" is a colony of...

s, and in aquarium
Aquarium
An aquarium is a vivarium consisting of at least one transparent side in which water-dwelling plants or animals are kept. Fishkeepers use aquaria to keep fish, invertebrates, amphibians, marine mammals, turtles, and aquatic plants...

s they will happily stick to glass walls of the tank, as well.

Gobies are primarily fish of shallow marine habitats including tide pool
Tide pool
Tide pools are rocky pools by oceans that are filled with seawater. Many of these pools exist as separate entities only at low tide.Tide pools are habitats of uniquely adaptable animals that have engaged the special attention of naturalists and marine biologists, as well as philosophical...

s, coral reef
Coral reef
Coral reefs are underwater structures made from calcium carbonate secreted by corals. Coral reefs are colonies of tiny living animals found in marine waters that contain few nutrients. Most coral reefs are built from stony corals, which in turn consist of polyps that cluster in groups. The polyps...

s, and seagrass meadows; they are also very numerous in brackish water
Brackish water
Brackish water is water that has more salinity than fresh water, but not as much as seawater. It may result from mixing of seawater with fresh water, as in estuaries, or it may occur in brackish fossil aquifers. The word comes from the Middle Dutch root "brak," meaning "salty"...

 and estuarine habitats, including the lower reaches of rivers, mangrove swamps, and salt marsh
Salt marsh
A salt marsh is an environment in the upper coastal intertidal zone between land and salt water or brackish water, it is dominated by dense stands of halophytic plants such as herbs, grasses, or low shrubs. These plants are terrestrial in origin and are essential to the stability of the salt marsh...

es. A small number of gobies (unknown exactly, but in the low hundreds) are also fully adapted to freshwater
Freshwater
Fresh water is naturally occurring water on the Earth's surface in ice sheets, ice caps, glaciers, bogs, ponds, lakes, rivers and streams, and underground as groundwater in aquifers and underground streams. Fresh water is generally characterized by having low concentrations of dissolved salts and...

 environments. These include the Asian river gobies (Rhinogobius
Rhinogobius
Rhinogobius is a genus of primarily freshwater gobies native to tropical and temperate parts of Asia. Most are small, streamlined in shape, and often sexually dimorphic. Few are of commercial importance, but R. duospilus Rhinogobius is a genus of primarily freshwater gobies native to tropical and...

spp.), the Australian desert goby (Chlamydogobius eremius
Chlamydogobius
Chlamydogobius is a genus of freshwater fish in the family Gobiidae .They live in extreme environments; for example, several species of Chlamydogobius are found in the water that emerges from geothermal springs in Australia, such as the Dalhousie goby, found in the waters around Dalhousie Springs,...

), and the European freshwater goby Padogobius bonelli
Padogobius bonelli
Padogobius bonelli is a species of fish in the Gobiidae family. It is found in Croatia, Italy, Slovenia, and Switzerland.Its natural habitat is rivers. It is threatened by habitat loss.-References:...

. Most gobies feed on small invertebrates, although some of the larger species eat other fish, and a few eat planktic algae
Algae
Algae are a large and diverse group of simple, typically autotrophic organisms, ranging from unicellular to multicellular forms, such as the giant kelps that grow to 65 meters in length. They are photosynthetic like plants, and "simple" because their tissues are not organized into the many...

.

Mudskippers

Mudskippers are highly specialized members of the family, usually ascribed to the subfamily Oxudercinae. They are able to survive for extended periods on land through a combination of behavioral and physiological adaptations, including pectoral fins that act as simple legs; the ability to breathe through their skins (like frogs); and the digging of damp burrows to avoid drying out. Mudskippers live in tidal areas, particularly on mudflats and in mangrove forests, and are only found in tropical and subtropical regions.

Reproduction

Gobies attach their eggs to a substrate, such as vegetation, coral, or a rock surface. They can lay anywhere from five to a few hundred eggs, depending on species. After fertilizing the eggs, the male remains to guard them from predators and keep them free from detritus. The eggs hatch after a few days. The larvae are born transparent, developing their coloration after dispersing to find a suitable habitat. The larvae of many freshwater species are carried downstream to the brackish waters of estuaries, or even to the sea, and only return to fresh water weeks or months later.

Gobies in warmer waters reach adulthood in a matter of months, while those in cooler environments may take up to two years. The total lifespan of gobies varies from a single year to up to ten years, again with the temperate species generally living longer.

A few species of goby are known to be able to change sex from female to male, although most do not do this. In such species, most individuals are born female, and the male must expend considerable effort in guarding the eggs of the multiple females with which he breeds.

Symbiosis

Gobies sometimes form symbiotic relationships
Symbiosis
Symbiosis is close and often long-term interaction between different biological species. In 1877 Bennett used the word symbiosis to describe the mutualistic relationship in lichens...

 with other species. Some goby species live in symbiosis with burrowing shrimps. The shrimp maintains a burrow in the sand in which both the shrimp and the goby live. The shrimp has poor eyesight compared to the goby, but if it sees or feels the goby suddenly swim into the burrow, it will follow. The goby and shrimp keep in contact with each other, the shrimp using its antennae, and the goby flicking the shrimp with its tail when alarmed. These gobies are thus sometimes known as watchmen or prawn gobies. Each party gains from this relationship: the shrimp gets a warning of approaching danger, and the goby gets a safe home and a place to lay its eggs. Only the alpha male and female reproduce, other fish in colony eat sparingly to resist being eaten by the alpha male or female. This way only the largest and fittest are able to reproduce.

Another example of symbiosis is demonstrated by the neon gobies (Elacatinus
Elacatinus
Elacatinus is a genus of marine gobies, often known collectively as the neon gobies. Although only one species, E. oceanops, is technically the "neon goby," because of their extremely similar appearance other members of the genus are generally labeled neon gobies as well.-Description:Neon gobies...

spp.). These gobies are known as "cleaner gobies", and remove parasites from the skin, fins, mouth, and gills of a wide variety of large fish. The most remarkable aspect of this symbiosis is that many of the fish that visit the gobies' cleaning station
Cleaning station
A cleaning station is a location where fish, sea turtles, hippo and other aquatic life, freshwater and marine, congregate to be cleaned.The cleaning process includes the removal of parasites from the animal's body , and can be performed by various creatures A cleaning station is a location where...

s would otherwise treat such small fish as food (for example, grouper
Grouper
Groupers are fish of any of a number of genera in the subfamily Epinephelinae of the family Serranidae, in the order Perciformes.Not all serranids are called groupers; the family also includes the sea basses. The common name grouper is usually given to fish in one of two large genera: Epinephelus...

s and snapper
Lutjanidae
Snappers are a family of perciform fish, mainly marine but with some members inhabiting estuaries, feeding in freshwater. Some are important food fish. One of the best known is the red snapper....

s). Again, this is a relationship where both parties gain: the gobies get a continual supply of food as bigger fish visit their cleaning stations, and the bigger fish leave the cleaning stations healthier than they were when they arrived.

In aquariums

Several species of gobies are kept in aquariums. Most captive gobies are species from saltwater, and make excellent additions to healthy reef or fish-only aquariums. Perhaps the most popular is the small but colorful neon goby. Most gobies stay toward the lower portion of the aquarium, hiding in the rockwork, but some species (most notably the shrimp gobies) prefer to dig themselves little burrows. Potential keepers of these striking fish should provide them with a fine grained substrate to prevent damage to their delicate undersides. Commonly kept saltwater species include the engineer goby, Randall's shrimp goby, and watchman goby. The bumblebee gobies from the genus Brachygobius
Brachygobius
Brachygobius is a small genus of gobies. They are popular aquarium fish where a number of species are sold as bumblebee gobies because their colours are similar to those of bumblebees.-Morphology:...

are perhaps the most widely traded freshwater species, being small, colorful, and easy to care for. They need tropical, hard and alkaline freshwater or slightly brackish conditions to do well. Gobies are generally peaceful towards their tankmates, though territorial among themselves. Since most are small and few are predatory toward other fishes, they usually make good community fishes
Community tank
Community aquaria are tanks that are designed to contain more than one species of fish. Most commonly they include a variety of species that do not normally occur together in nature, for example angelfish from Brazil, swordtails from Mexico, and gouramis from South East Asia...

. Typically, the main problem with gobies is feeding them: with a few exceptions, the small species kept in aquariums prefer live on frozen foods rather than flake, and they are not very good at competing with active species such as cichlid
Cichlid
Cichlids are fishes from the family Cichlidae in the order Perciformes. Cichlids are members of a group known as the Labroidei along with the wrasses , damselfish , and surfperches . This family is both large and diverse. At least 1,300 species have been scientifically described, making it one of...

s. Another problem is that it is very common for them to jump out of the tank so having a tight fitting lid is a must. It is often recommended that gobies be kept on their own or with peaceful surface dwelling species such as halfbeak
Halfbeak
The halfbeaks are a geographically widespread and numerically abundant family of epipelagic fish inhabiting warm waters around the world. The family Hemiramphidae is divided into two subfamilies, the primarily marine Hemiramphinae and the freshwater or estuarine Zenarchopterinae...

s and guppies
Guppy
The guppy , also known as the millionfish, is one of the most popular freshwater aquarium fish species in the world. It is a small member of the Poeciliidae family [females long, males long] and like all other members of the family, is live-bearing....

.

See also

  • Sleeper gobies are a closely related family (Eleotridae) that lack the fused pelvic fin sucker typical of most gobies, but are otherwise very similar in size, shape, and ecology.
  • Blennies are a group of shallow water marine fish often confused with gobies.
  • Dragonet
    Dragonet
    Dragonets are small, perciform, marine fish of the diverse family Callionymidae . Found mainly in the tropical waters of the western Indo-Pacific, the family contains approximately 186 species in 18 genera. The Draconettidae may be considered a sister family, whose members are very much alike,...

    s are superficially similar to gobies and sometimes confused with them.

External links

The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
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