Ostraciidae or Ostraciontidae is a family of squared, bony fish belonging to the order Tetraodontiformes, closely related to the pufferfishes and filefishes. Fish in the family are known variously as boxfishes, cofferfishes, cowfishes and trunkfishes. It contains about 23 extant species in 6 extant genera.
Taxonomy
Ostraciidae was first proposed as a family in 1810 by the French polymath Constantine Samuel Rafinesque. In the past this grouping was regarded as a subfamily, the Ostraciinae, along with the subfamily Aracaninae, of a wider Ostraciidae. However, recent phylogenetic studies have concluded that the families Aracanidae and Ostraciidae are valid families but that they are part of the same clade, the suborder Ostracioidei. The 5th edition of Fishes of the World classifies this clade as the suborder Ostracioidea within the order Tetraodontiformes.
Etymology
Ostraciidae takes its name from its type genus, Ostracion, a name which means "little box" and is an allusion to the shape of the body of its type species, O. cubicus.
Description
Ostraciidae boxfishes occur in a variety of colors, and are noted for the hexagonal or "honeycomb" patterns on their skin. They swim in a rowing manner. Their hexagonal plate-like scales are fused into a solid, triangular or box-like carapace, 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. 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, Indian, and Pacific oceans, An example of this is pahutoxin, a water-soluble, crystalline chemical toxin 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 found in echinoderms.
Classification
The author Keiichi Matsuura lists the following genera and species:
{| class="wikitable"
|+
!Genus
!Species
!Image
|-
|Acanthostracion <small>Bleeker, 1865</small>
|
- A. guineense <small>(Bleeker, 1865)</small> (West African cowfish)
- A. notacanthus <small>(Bleeker, 1863)</small> (Island cowfish)
- A. polygonius <small>Poey, 1876</small> (Honeycomb cowfish)
- A. quadricornis <small>(Linnaeus, 1758)</small> (Scrawled cowfish)
|frameless
<small>A. quadricornis</small>
|-
|Lactophrys <small>Swainson, 1839</small>
|
- L. bicaudalis <small>(Linnaeus, 1758)</small>
- L. trigonus <small>(Linnaeus, 1758)</small>
- L. triqueter <small>(Linnaeus, 1758)</small>
|frameless
<small>L. triqueter</small>
|-
|Lactoria <small>D. S. Jordan & Fowler, 1902</small>
|
- L. cornuta <small>(Linnaeus, 1758)</small>
- L. diaphana <small>(Bloch & J. G. Schneider, 1801)</small>
- L. fornasini <small>(Bianconi, 1846)</small>
|frameless
<small>L. cornuta</small>
|-
|Ostracion <small>Linnaeus, 1758</small>
|
- O. cubicum <small>Linnaeus, 1758</small> (Yellow boxfish)
- O. cyanurus <small>Rüppell, 1828</small> (Bluetail trunkfish)
- O. immaculatum <small>Temminck & Schlegel, 1850</small> (Bluespotted boxfish)
- O. meleagris <small>G. Shaw, 1796</small> (White-spotted boxfish)
- O. nasus <small>Bloch, 1785</small> (Shortnose boxfish)
- O. rhinorhynchos <small>Bleeker, 1851</small> (Horn-nosed boxfish)
- O. solorense <small>Bleeker, 1853</small> (Reticulate boxfish)
- O. trachys <small>J. E. Randall, 1975</small> (Roughskin trunkfish)
- O. whitleyi <small>Fowler, 1931</small> (Whitley's boxfish)
|frameless
<small>O. meleagris</small>
|-
|Paracanthostracion <small>Whitley, 1933</small>
|
- P. lindsayi <small>(Phillipps, 1932)</small>
|
|-
|Tetrosomus <small>Swainson, 1839</small>
|
- T. concatenatus <small>(Bloch, 1785)</small> (Triangular boxfish)
- T. gibbosus <small>(Linnaeus, 1758)</small> (Camel cowfish)
- T. reipublicae <small>(Whitley, 1930)</small> (Smallspine turretfish)
- T. stellifer <small>(Bloch & Schneider, 1801)</small>
|frameless
<small>T. gibbosus</small>
|}
Fossil taxa
{| class="wikitable"
|+
!Genus
!Species
!Image
|-
|†Eolactoria <small>Tyler, 1975</small>
|†Eolactoria sorbinii <small>Tyler 1976</small> (Lutetian of Monte Bolca, Eocene Italy)
|frameless
|-
|†Oligolactoria <small>Tyler & Gregorova, 1991</small>
|†Oligolactoria bubiki <small>Tyler & Gregorova, 1991</small>(Rupelian of Moravia, Oligocene Czech Republic)
|frameless
|}