Onychoteuthis is a genus

Genus

In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...

 of squid

Squid

Squid are cephalopods of the order Teuthida, which comprises around 300 species. Like all other cephalopods, squid have a distinct head, bilateral symmetry, a mantle, and arms. Squid, like cuttlefish, have eight arms arranged in pairs and two, usually longer, tentacles...

 in the family Onychoteuthidae. The type species

Type species

In biological nomenclature, a type species is both a concept and a practical system which is used in the classification and nomenclature of animals and plants. The value of a "type species" lies in the fact that it makes clear what is meant by a particular genus name. A type species is the species...

 is the Common Clubhook Squid

Common Clubhook Squid

The Common Clubhook Squid is a species of squid in the family Onychoteuthidae. It is the type species of the genus Onychoteuthis.-References:...

 (Onychoteuthis banksii). While the genus is found worldwide in tropical and subtropical oceans, they can also occur in the North Pacific Ocean.

Anatomy

Most species

Species

In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...

 belonging to the genus have a mantle

Mantle (mollusc)

The mantle is a significant part of the anatomy of molluscs: it is the dorsal body wall which covers the visceral mass and usually protrudes in the form of flaps well beyond the visceral mass itself.In many, but by no means all, species of molluscs, the epidermis of the mantle secretes...

 length of under 200 mm, however the larger members may measure over 300 mm. Bilobed photophore

Photophore

A photophore is a light-emitting organ which appears as luminous spots on various marine animals, including fish and cephalopods. The organ can be simple, or as complex as the human eye; equipped with lenses, shutters, color filters and reflectors...

s are found upon the surface of each eyeball. The temporary conjunction of the arm

Cephalopod arm

A cephalopod arm is distinct from a tentacle, though the terms are often used interchangeably.Generally, cephalopod arms have suckers along most of their length, as opposed to tentacles, which have suckers only near their ends. Octopuses have eight arms and no tentacles, while squid and cuttlefish...

s by means of the suckers enables them to act in combination. The animal has long prehensile arms, the clavate extremities of which are provided with suckers and a double row of hooks.

Species

• Onychoteuthis banksii
• Onychoteuthis bergii
• Onychoteuthis mollis
• Onychoteuthis compacta
  Onychoteuthis compacta
  Onychoteuthis compacta is a species of squid in the family Onychoteuthidae, known to occur in Hawaiian waters. The species is known to have a mantle length of at least 122 mm for females and 127 mm for males. Each tentacle has 22 club hooks, measuring approximately 30 mm in mature...
  
  
• Onychoteuthis borealijaponica
• Onychoteuthis meridiopacifica
  Onychoteuthis meridiopacifica
  Onychoteuthis meridiopacifica is a species of squid in the family Onychoteuthidae. Males become mature at 40 mm, and the species is believed to reach a maximum mantle length of 90 mm. The tantacular club reaches a length of 20-25% of the mantle length, and contains 16-19 club hooks. Arms...
  
  
• Onychoteuthis lacrima
• Onychoteuthis prolata

Former species

The following four species have been reassigned to other genera.

• Onychoteuthis fabricii now in Gonatus
  Gonatus
  Gonatus is a genus of squid in the family Gonatidae, comprising twelve species, and therefore containing the most species in the family. Adult squid belonging to species in this genus are notable for their lack of tentacles.-Species:...
  
  
• Onychoteuthis ingens now in Onykia
  Onykia
  Onykia is a genus of squids in the family Onychoteuthidae. Due to similarities between the genera, several recent authors consider the genus Moroteuthis a junior synonym of Onykia. The type species is the Tropical Clubhook Squid ....
  
  
• Onychoteuthis lesueurii now in Ancistrocheirus
• Onychoteuthis lichtensteinii now in Ancistroteuthis

External links

• Tree of Life web project: Onychoteuthis