Ostraciidae is a family of squared,

bony fish Osteichthyes (), popularly referred to as the bony fish, is a diverse superclass of fish that have skeletons primarily composed of bone tissue. They can be contrasted with the Chondrichthyes, which have skeletons primarily composed of cartila ...

belonging to the order

Tetraodontiformes The Tetraodontiformes are an order of highly derived ray-finned fish, also called the Plectognathi. Sometimes these are classified as a suborder of the order Perciformes. The Tetraodontiformes are represented by 10 extant families and at least ...

, closely related to the

pufferfish Tetraodontidae is a family of primarily marine and estuarine fish of the order Tetraodontiformes. The family includes many familiar species variously called pufferfish, puffers, balloonfish, blowfish, blowies, bubblefish, globefish, swellfi ...

es and

filefish The filefish (Monacanthidae) are a diverse family of tropical to subtropical tetraodontiform marine fish, which are also known as foolfish, leatherjackets or shingles. They live in the Atlantic, Pacific and Indian Oceans. Filefish are closely ...

es. Fish in the family are known variously as boxfishes, cofferfishes, cowfishes and trunkfishes. It contains about 23 extant

species In biology, a species is the basic unit of Taxonomy (biology), 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 ...

in 6 extant

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 ...

Description

Members of this family occur in a variety of different colors, and are notable for the

hexagon In geometry, a hexagon (from Greek , , meaning "six", and , , meaning "corner, angle") is a six-sided polygon. The total of the internal angles of any simple (non-self-intersecting) hexagon is 720°. Regular hexagon A ''regular hexagon'' h ...

al or "honeycomb" patterns on their skin. They swim in a rowing manner. Their hexagonal plate-like scales are fused together into a solid, triangular or box-like

carapace A carapace is a dorsal (upper) section of the exoskeleton or shell in a number of animal groups, including arthropods, such as crustaceans and arachnids, as well as vertebrates, such as turtles and tortoises. In turtles and tortoises, the und ...

, from which the fins, tail, eyes and mouth protrude. Because of these heavy armoured scales, Ostraciidae are limited to slow movements, but few other fish are able to eat the adults. Ostraciid boxfish of the genus '' Lactophrys'' also secrete poisons from their skin into the surrounding water, further protecting them from

predation Predation is a biological interaction In ecology, a biological interaction is the effect that a pair of organisms living together in a community have on each other. They can be either of the same species (intraspecific interactions), or o ...

. Although the adults are in general quite square in shape, young Ostraciidae are more rounded. The young often exhibit brighter colors than the adults. The scrawled cowfish, ''Acanthostracion quadricornis'', can grow up to in length, but is generally smaller at higher latitudes.

Range

Ostraciids occur in 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 ...

, Indian, and

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 contine ...

s, generally at middle latitudes, although the common or buffalo trunkfish ('' Lactophrys trigonus'') which lives mainly in

Florida Florida is a state located in the Southeastern region of the United States. Florida is bordered to the west by the Gulf of Mexico, to the northwest by Alabama, to the north by Georgia, to the east by the Bahamas and Atlantic Ocean, a ...

waters may be found as far north as

Cape Cod Cape Cod is a peninsula extending into the Atlantic Ocean from the southeastern corner of mainland Massachusetts, in the northeastern United States. Its historic, maritime character and ample beaches attract heavy tourism during the summer mon ...

Toxic defences

The various members of this family are able to secrete cationic

surfactants Surfactants are chemical compounds that decrease the surface tension between two liquids, between a gas and a liquid, or interfacial tension between a liquid and a solid. Surfactants may act as detergents, wetting agents, emulsifiers, foaming a ...

through their skin which can act as a chemical defense mechanism. An example of this is pahutoxin, a water-soluble, crystalline chemical

toxin A toxin is a naturally occurring organic poison produced by metabolic activities of living cells or organisms. Toxins occur especially as a protein or conjugated protein. The term toxin was first used by organic chemist Ludwig Brieger (1849 ...

that is contained in mucus secreted from the skin of ''Ostracion lentiginosus'' and other members of the trunkfish family when they are under stress. Pahutoxin is a choline chloride ester of 3-acetoxypalmitic acid that behaves similarly to steroidal

saponins Saponins (Latin "sapon", soap + "-in", one of), also selectively referred to as triterpene glycosides, are bitter-tasting usually toxic plant-derived organic chemicals that have a foamy quality when agitated in water. They are widely distributed ...

found in

echinoderms An echinoderm () is any member of the phylum Echinodermata (). The adults are recognisable by their (usually five-point) radial symmetry, and include starfish, brittle stars, sea urchins, sand dollars, and sea cucumbers, as well as the ...

. When this toxic mucus is released from the fish, it quickly dissolves in the environment and negatively affects any fish in the surrounding area. It is possible since this toxin resembles certain detergents so closely, that adding these detergents as pollutants to seawater has potential to interfere with receptor-mediated processes in marine life.

Classification

Humpback Turretfish - Tetrosomus gibbosus 2

The author Keiichi Matsuura lists the following genera and species:

Fossil taxa

* Genus '' Eolactoria'' ** ''Eolactoria sorbinii'' Tyler 1976 (

Lutetian The Lutetian is, in the geologic timescale, a stage (stratigraphy), stage or age (geology), age in the Eocene. It spans the time between . The Lutetian is preceded by the Ypresian and is followed by the Bartonian. Together with the Bartonian it ...

Monte Bolca Monte Bolca is a lagerstätte near Verona, Italy that was one of the first fossil sites with high quality preservation known to Europeans, and is still an important source of fossils from the Eocene. Geology Monte Bolca was uplifted from the T ...

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'', " ...

Italy Italy ( it, Italia ), officially the Italian Republic, ) or the Republic of Italy, is a country in Southern Europe. It is located in the middle of the Mediterranean Sea, and its territory largely coincides with the homonymous geographical ...

) * Genus '' Oligolactoria'' ** ''Oligolactoria bubiki'' Tyler 1980 (

Rupelian The Rupelian is, in the geologic timescale, the older of two ages or the lower of two stages of the Oligocene Epoch/ Series. It spans the time between . It is preceded by the Priabonian Stage (part of the Eocene) and is followed by the Chattian ...

Moravia Moravia ( , also , ; cs, Morava ; german: link=yes, Mähren ; pl, Morawy ; szl, Morawa; la, Moravia) is a historical region in the east of the Czech Republic and one of three historical Czech lands, with Bohemia and Czech Silesia. Th ...

Oligocene The Oligocene ( ) is a geologic epoch of the Paleogene Period and extends from about 33.9 million to 23 million years before the present ( to ). As with other older geologic periods, the rock beds that define the epoch are well identified but ...

Czech Republic The Czech Republic, or simply Czechia, is a landlocked country in Central Europe. Historically known as Bohemia, it is bordered by Austria to the south, Germany to the west, Poland to the northeast, and Slovakia to the southeast. Th ...

)

Extant taxa

* ''

Acanthostracion ''Acanthostracion'' is a genus of boxfishes native to the Atlantic Ocean. Species There are currently 4 recognized species in this genus:Matsuura, K. (2014): Taxonomy and systematics of tetraodontiform fishes: a review focusing primarily on prog ...

'' * '' Lactophrys'' * '' Lactoria'' * '' Ostracion'' * ''

Paracanthostracion ''Paracanthostracion lindsayi'' is a species of boxfish endemic to New Zealand. This species is the only known member of the genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and f ...

'' * '' Tetrosomus''

References

{{Taxonbar, from=Q755011 Marine fish families Taxa named by Constantine Samuel Rafinesque