''Taningia'' is a

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

squid A squid (: squid) is a mollusc with an elongated soft body, large eyes, eight cephalopod limb, arms, and two tentacles in the orders Myopsida, Oegopsida, and Bathyteuthida (though many other molluscs within the broader Neocoleoidea are also ...

, one of the two referred to as

octopus squid The Octopoteuthidae are a family (biology), family of squid comprising two genus, genera. The family is characterized by tentacles which cease to grow after the paralarval stage which leads to the adult having eight arms; thus, members of this fa ...

(

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

Octopoteuthidae The Octopoteuthidae are a family of squid comprising two genera. The family is characterized by tentacles which cease to grow after the paralarval stage which leads to the adult having eight arms; thus, members of this family are commonly named ...

), the other being ''

Octopoteuthis ''Octopoteuthis'' is a genus of squid, one of the two referred to as octopus squid (family Octopoteuthidae), the other being '' Taningia'', its sister genus. Both ''Octopoteuthis'' and ''Taningia'' are characterized by their lack of tentacles f ...

'', its

sister genus In phylogenetics, a sister group or sister taxon, also called an adelphotaxon, comprises the closest relative(s) of another given unit in an evolutionary tree. Definition The expression is most easily illustrated by a cladogram: Taxon A and t ...

. Both ''Octopoteuthis'' and ''Taningia'' are characterized by their lack of

tentacle In zoology, a tentacle is a flexible, mobile, and elongated organ present in some species of animals, most of them invertebrates. In animal anatomy, tentacles usually occur in one or more pairs. Anatomically, the tentacles of animals work main ...

s for the majority of their life cycle, which led to their

common name In biology, a common name of a taxon or organism (also known as a vernacular name, English name, colloquial name, country name, popular name, or farmer's name) is a name that is based on the normal language of everyday life; and is often con ...

Classification

This genus is named after Danish

fisheries Fishery can mean either the enterprise of raising or harvesting fish and other aquatic life or, more commonly, the site where such enterprise takes place ( a.k.a., fishing grounds). Commercial fisheries include wild fisheries and fish farm ...

biologist

Åge Vedel Tåning Åge Vedel Tåning (27 July 1890 – 26 September 1958 in Copenhagen) was a Danish ichthyologist. He was a director of the Carlsberg Laboratory, the Dana collection and the Danish Fisheries Research Station. Taxon named in his honor *Lantern ...

(1890-1958). ''Taningia'' is separated from ''Octopoteuthis'' by adults possessing a large

photophore A photophore is a specialized anatomical structure found in a variety of organisms that emits light through the process of boluminescence. This light may be produced endogenously by the organism itself (symbiotic) or generated through a mut ...

on the tips of arm pair II (second pair from the

dorsal Dorsal (from Latin ''dorsum'' ‘back’) may refer to: * Dorsal (anatomy), an anatomical term of location referring to the back or upper side of an organism or parts of an organism * Dorsal, positioned on top of an aircraft's fuselage The fus ...

), which are the only known photophores on the body along with the

ink sac An ink sac is an anatomical feature that is found in many cephalopod mollusks used to produce the defensive cephalopod ink. With the exception of nocturnal and very deep water cephalopods, all Coleoidea (squid, octopus and cuttlefish) which dwell ...

organ (''Octopoteuthis'' has photophores on each arm-tip and spread around its body). The photophores, around the size of

lemon The lemon (''Citrus'' × ''limon'') is a species of small evergreen tree in the ''Citrus'' genus of the flowering plant family Rutaceae. A true lemon is a hybrid of the citron and the bitter orange. Its origins are uncertain, but some ...

s, possesses

eyelid An eyelid ( ) is a thin fold of skin that covers and protects an eye. The levator palpebrae superioris muscle retracts the eyelid, exposing the cornea to the outside, giving vision. This can be either voluntarily or involuntarily. "Palpebral ...

-like skin flaps which conceal the light organs when needed. The genus reaches in mantle length ( ML), though has also been reported. This genus possesses two rows of arm hooks on each arm pair, which develop after ML; a single photophore may also develop on the ink sac at this size. The

paralarva Coleoidea or Dibranchiata is one of the two subclasses of cephalopod molluscs containing all the various taxa popularly thought of as "soft-bodied" or "shell-less" (i.e. octopus, squid and cuttlefish). Unlike its extant sister group Nautiloidea ...

e have robust tentacular stalks; these disappear at ML, leaving the squid with eight arms. Additional diagnostic characters include arms being 25-58% of ML, with arm pair II being the shortest, each arm having a single broad buccal connective (membrane connecting the arm to the mass of the mouth), and the mantle cartilage being broad, and blunt towards the head. Traditionally, this genus is considered to be

monotypic In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unisp ...

, with only ''Taningia danae'' as a valid species. ''T. persica'' was named from a paralarval specimen in 1923, and it is currently considered a ''

species inquirenda In biological classification, a ''species inquirenda'' is a species of doubtful identity requiring further investigation. The use of the term in English-language biological literature dates back to at least the early nineteenth century. The ter ...

'' due to the uncertain identity of the holotype. A 2019

thesis A thesis (: theses), or dissertation (abbreviated diss.), is a document submitted in support of candidature for an academic degree or professional qualification presenting the author's research and findings.International Standard ISO 7144: D ...

recovered more species in this genus, but these have not yet been accepted by various online

taxonomic database A taxonomic database is a database created to hold information on biological taxa – for example groups of organisms organized by species name or other taxonomic identifier – for efficient data management and information retrieval. Taxonomic dat ...

s. The species recovered by the 2019 study are as follows: *''

Taningia danae ''Taningia danae'', the Dana octopus squid, is a species of squid in the family Octopoteuthidae, the octopus squids. It is one of the Cephalopod size, largest known squid species, and it has one of the largest photophores (light organs) known in ...

'', Dana octopus squid: possible earliest specimen ''Cucioteuthis unguiculata'' from the

South Pacific The Pacific Ocean is the largest and deepest of Earth's five Borders of the oceans, oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean, or, depending on the definition, to Antarctica in the south, and is ...

holotype A holotype (Latin: ''holotypus'') is a single physical example (or illustration) of an organism used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of s ...

from

Atlantic The Atlantic Ocean is the second largest of the world's five oceanic divisions, with an area of about . It covers approximately 17% of Earth's surface and about 24% of its water surface area. During the Age of Discovery, it was known for se ...

, semi-

cosmopolitan Cosmopolitan may refer to: Internationalism * World citizen, one who eschews traditional geopolitical divisions derived from national citizenship * Cosmopolitanism, the idea that all of humanity belongs to a single moral community * Cosmopolitan ...

*'' Taningia fimbria'': Southern Hemisphere, between 30° and 50°S *'' Taningia rubea'': Northwestern Pacific *''Taningia sp.'' IV:

Temperate In geography, the temperate climates of Earth occur in the middle latitudes (approximately 23.5° to 66.5° N/S of the Equator), which span between the tropics and the polar regions of Earth. These zones generally have wider temperature ran ...

Northeastern Pacific *''Taningia sp.'' V: Atlantic including the

Gulf of Mexico The Gulf of Mexico () is an oceanic basin and a marginal sea of the Atlantic Ocean, mostly surrounded by the North American continent. It is bounded on the northeast, north, and northwest by the Gulf Coast of the United States; on the southw ...

File:Taningia persica.png, Holotype of ''Taningia persica'', a paralarval specimen. The ink sac is visible through the transparent mantle File:Taningia persica arms.png, ''

idem ''idem'' is a Latin term meaning "the same". It is commonly abbreviated as ''id.'', which is particularly used in legal citations to denote the previously cited source (compare '' ibid.''). It is also used in academic citations to replace the ...

'', limbs. The pair of tentacles possess large suckers on their tips

References

External links

Tree of Life web project: ''Taningia''
{{Taxonbar, from=Q3021386 Octopoteuthidae Cephalopod genera Bioluminescent molluscs