| Ostraciidae | |
|---|---|
 | |
| Yellow boxfishOstracion cubicus | |
Scientific classification | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Actinopterygii |
| Order: | Tetraodontiformes |
| Suborder: | Ostracioidea |
| Family: | Ostraciidae Rafinesque, 1810 |
| Genera | |
See text | |
Ostraciidae orOstraciontidae is a family of squared,bony fish belonging to the orderTetraodontiformes, closely related to thepufferfishes andfilefishes. Fish in the family are known variously asboxfishes,cofferfishes,cowfishes andtrunkfishes. It contains about 23 extantspecies in 6 extantgenera.
Ostraciidae was first proposed as a family in 1810 by the FrenchpolymathConstantine Samuel Rafinesque.[1] In the past this grouping was regarded as asubfamily, the Ostraciinae, along with the subfamily Aracaninae, of a wider Ostraciidae. However, recentphylogenetic studies have concluded that the familiesAracanidae and Ostraciidae are valid families but that they are part of the same clade, the suborderOstracioidei.[2] The 5th edition ofFishes of the World classifies this clade as the suborder Ostracioidea within the order Tetraodontiformes.[3]
Ostraciidae takes its name from itstype genus,Ostracion, a name which means "little box" and is an allusion to the shape of the body of itstype species,O. cubicus.[4]
Ostraciidae boxfishes occur in a variety of different colors, and are notable for thehexagonal 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-likecarapace, 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 genusLactophrys also secrete poisons from their skin into the surrounding water, further protecting them frompredation.[5] Although the adults are in general quite square in shape, young Ostraciidae are more rounded. The young often exhibit brighter colors than the adults. Thescrawled cowfish,Acanthostracion quadricornis, can grow up to 50 centimetres (20 in) in length, but is generally smaller at higher latitudes.[citation needed]
Ostraciids occur in theAtlantic,Indian, andPacific oceans,[3] generally at middle latitudes, although the common orbuffalo trunkfish (Lactophrys trigonus) which lives mainly inFlorida waters may be found as far north asCape Cod.[citation needed]
The various members of this family are able to secrete cationicsurfactants through their skin which can act as a chemical defense mechanism.[6] An example of this ispahutoxin, a water-soluble, crystalline chemicaltoxin that is contained in mucus secreted from the skin ofOstracion lentiginosus and other members of the trunkfish family when they are under stress.[7] Pahutoxin is acholine chloride ester of 3-acetoxypalmitic acid[8] that behaves similarly to steroidalsaponins found inechinoderms.[7] 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.[9]
The author Keiichi Matsuura lists the following genera and species:[2]
There are about 25 recognized extant species in six genera:[3][10]
| Genus | Species | Image |
|---|---|---|
| AcanthostracionBleeker, 1865 |
|  |
| LactophrysSwainson, 1839 |  | |
| LactoriaD. S. Jordan &Fowler, 1902 |
|  |
| OstracionLinnaeus, 1758 |
| .jpg) |
| ParacanthostracionWhitley, 1933 |
| |
| TetrosomusSwainson, 1839 |
|  |
| Genus | Species | Image |
|---|---|---|
| †EolactoriaTyler, 1975 | †Eolactoria sorbiniiTyler 1976 (Lutetian ofMonte Bolca,EoceneItaly) |  |
| †OligolactoriaTyler &Gregorova, 1991 | †Oligolactoria bubikiTyler & Gregorova, 1991(Rupelian ofMoravia,OligoceneCzech Republic) |  |
