Bathyteuthis is the singular 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 Bathyteuthidae, encompassing three species. None obtain 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 greater than 80 mm.

Bathyteuthis are found scattered throughout the world’s oceans at mesopelagic

Mesopelagic

The mesopelagic is that part of the pelagic zone that extends from a depth of 200 to 1000 metres below the ocean surface. It lies between the photic epipelagic above and the aphotic bathypelagic below, where there is no light at all...

 to bathypelagic depths, commonly between 700 and 2,000 meters.

Description

The arms on Bathyteuthis are short, joined by a low, fleshy web, with suckers arranged in irregular rows (2 proximally increasing to 4 distally). Tentacular clubs are short and narrow, with 8-10 longitudinal series of numerous, minute suckers. Buccal connectives which have small suckers attach to the dorsal border of the ventral arms (arms IV). Fins are small, round and separate. The head has tentacle pockets and the eyes are turned slightly to the front. Females have paired oviduct

Oviduct

In non-mammalian vertebrates, the passageway from the ovaries to the outside of the body is known as the oviduct. The eggs travel along the oviduct. These eggs will either be fertilized by sperm to become a zygote, or will degenerate in the body...

s. Suckers lack circularis muscles.

Taxonomy

Bathyteuthis shares some characters with oegopsin

Oegopsina

Oegopsina is a suborder of the squid order, Teuthida, in the Cephalopod Class. Some taxonomists raise it to the level of an order, in which case it is known as Oegopsida....

 squid and others with the Myopsina

Myopsina

Myopsina is a suborder of squid containing two families. Some systematists raise it to the level of an order, in which case it is known as Myopsida.-External links:*...

, hence its placement in a separate suborder, the Bathyteuthoidea

Bathyteuthoidea

The Bathyteuthoidea are small, mesopelagic to bathypelagic squid that in some ways resemble myopsid squid, such as Loligo and in others the pelagic oegopsid squid...

, by some authorities. The paired oviducts (in females) and suckers without circularis muscles are characteristic of ordinary Oegopsina. On the other hand buccal connective tissue with suckers and tentacle pockets in the head are characters found in Myopsin squid, but absent in the Oegopsina.

Species

• Bathyteuthis abyssicola
  Bathyteuthis abyssicola
  Bathyteuthis abyssicola, also known as the Deepsea Squid, is a species of squid in the family Bathyteuthidae.Bathyteuthis abyssicola is the type species of Bathyteuthis...
  
  , Deepsea Squid
• Bathyteuthis bacidifera
• Bathyteuthis berryi