Tetractenos

Superregnum: Eukaryota
Cladus: Unikonta
Cladus: Opisthokonta
Cladus: Holozoa
Regnum: Animalia
Subregnum: Eumetazoa
Cladus: Bilateria
Cladus: Nephrozoa
Superphylum: Deuterostomia
Phylum: Chordata
Subphylum: Vertebrata
Infraphylum: Gnathostomata
Megaclassis: Osteichthyes
Superclassis/Classis: Actinopterygii
Classis/Subclassis: Actinopteri
Subclassis/Infraclassis: Neopterygii
Infraclassis: Teleostei
Megacohors: Osteoglossocephalai
Supercohors: Clupeocephala
Cohors: Euteleosteomorpha
Subcohors: Neoteleostei
Infracohors: Eurypterygia
Sectio: Ctenosquamata
Subsectio: Acanthomorphata
Divisio/Superordo: Acanthopterygii
Subdivisio: Percomorphaceae
Series: Eupercaria
Ordo: Tetraodontiformes
Subordo: Tetraodontoidei

Familia: Tetraodontidae
Genus: Tetractenos
Species (2): T. glaber – T. hamiltoni
Name

Tetractenos (Hardy, 1983)

stralia's southern and eastern coastlines.
Species

There are currently two recognized species in this genus:[1]

Tetractenos glaber (Fréminville, 1813) (Smooth toadfish)
Tetractenos hamiltoni (J. Richardson, 1846) (Common toadfish)

Description

The general colour of the species in this genus varies, as at night they take on a deeper colour than during daytime, and, as with all toadfishes and puffers, the colour of skin changes slightly depending on the mood or stress level of the animal. For example, when a Tetractenos is in oxygen-depleted water, its underbelly will be a darker colour than the usual whitish-cream. The body of both species is covered in small, gravel-like pustules (spots). Small, sandpaper-like spines can be found on the body, and when the animal "puffs up" they stick out and make it feel even more rough.

Although the colour varies, T. hamiltoni is sandy to whitish in colour, with small brown spots over most of the back and upper sides, and brown bars and blotches beneath.[2] T. glaber has larger spots and blotches, and less prominent spines, hence its common name, smooth toadfish.[2]

The genus Tetractenos was once classed as Tetraodon or Tetrodon,[3] and is sometimes also confused with Torquigener.
References

Froese, Rainer and Pauly, Daniel, eds. (2012). Species of Tetractenos in FishBase. October 2012 version.
Australian Museum: Common Toadfish.
G.S. Hardy, "Revision of Australian species of Torquigener Whitley (Tetraodontiformes: Tetraodontidae), and two new generic names for Australian puffer fishes," Journal of the Royal Society of New Zealand, Volume 13, No. 1/2, 1983, pp. 1–48. [1]