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 cartilag ...

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, swellfis ...

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 rel ...

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 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 ...

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 nomenclat ...

Description

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

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

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 Dorsum (biology), 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 tor ...

, 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 ''Lactophrys'' is a genus of boxfishes native to the western Atlantic Ocean. All trunkfish of the genus ''Lactophrys'', secretes a colorless toxin from glands on its skin when touched. The toxin is only dangerous when ingested, so there is no imm ...

'' also secrete poisons from their skin into the surrounding water, further protecting them from

predation Predation is a biological interaction where one organism, the predator, kills and eats another organism, its prey. It is one of a family of common feeding behaviours that includes parasitism and micropredation (which usually do not kill the ...

. 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 The scrawled cowfish (''Acanthostracion quadricornis'') is a species of boxfish native to the western tropical and equatorial Atlantic, as well as the Gulf of Mexico. They range in size from , with a maximum length of , and can be found at depths ...

, ''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 Indian or Indians may refer to: Peoples South Asia * Indian people, people of Indian nationality, or people who have an Indian ancestor ** Non-resident Indian, a citizen of India who has temporarily emigrated to another country * South Asia ...

, 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 continen ...

s, generally at middle latitudes, although the common or buffalo trunkfish (''

Lactophrys trigonus ''Lactophrys trigonus'', commonly called the ''buffalo trunkfish'' or ''trunkfish'', is a boxfish native to the Western Atlantic. Description The trunkfish has small diffuse white spots. Two areas, located on the pectoral region and halfway betw ...

'') 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, and to ...

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 mont ...

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, emulsion#Emulsifiers , ...

through their skin which can act as a chemical defense mechanism. An example of this is

pahutoxin Pahutoxin, formerly called ostracitoxin, is a neurotoxin present in the mucous secretions of boxfish (Ostraciidae) skin, while under stress. It is an ichthyotoxic, hemolytic, nonpeptide (which is relatively unusual, although similar to tetrodotox ...

, 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 Choline chloride is an organic compound with the formula CH3)3NCH2CH2OHl. It is bifunctional, containing both quaternary ammonium salt and an alcohol. The cation is choline, which occurs naturally. It is a white, water-soluble salt (chemistry ...

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 sea li ...

. 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'' is an extinct prehistoric boxfish that lived during the Lutetian epoch of the middle Eocene, in Monte Bolca. It had two pairs of long spines, one over each eye, and one pair beneath the anal and caudal fins, arranged ve ...

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

Lutetian The Lutetian is, in the geologic timescale, a stage or 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 is sometimes referred to as the Midd ...

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 (geology), epoch that lasted from about 56 to 33.9 million years ago (mya). It is the second epoch of the Paleogene Period (geology), Period in the modern Cenozoic Era (geology), Era. The name ''Eocene' ...

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 re ...

) * Genus ''

Oligolactoria ''Oligolactoria bubiki'' is an extinct prehistoric boxfish that lived during the Rupelian epoch from the Middle Oligocene of Moravia, Czech Republic. In life, it would have strongly resembled a modern cowfish (genus ''Lactoria''). See also * ...

'' ** ''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. The me ...

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 the ...

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. The ...

)

Extant taxa

* '' Acanthostracion'' * ''

'' * ''

Lactoria ''Lactoria'' is a genus of boxfishes. Species Three species in this genus are recognized:Matsuura, K. (2014): Taxonomy and systematics of tetraodontiform fishes: a review focusing primarily on progress in the period from 1980 to 2014. ''Ichthyol ...

'' * ''

Ostracion ''Ostracion'' is a genus of the boxfish family Ostraciidae. Fish in the genus are known as box puffers. It was first described by Carl Linnaeus in 1758 and makes a brief appearance in Jules Verne's maritime sci-fi novel Twenty Thousand Leagues U ...

'' * '' Paracanthostracion'' * ''

Tetrosomus ''Tetrosomus'' is a genus of boxfishes native to the Indian Ocean, Indian and western Pacific Oceans. Species There are currently four recognized species in this genus:Matsuura, K. (2014): Taxonomy and systematics of tetraodontiform fishes: a re ...

References

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