Octopodiformes is a superorder of the subclass

Coleoidea 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 Nauti ...

, comprising the

octopus An octopus (: octopuses or octopodes) is a soft-bodied, eight-limbed mollusc of the order Octopoda (, ). The order consists of some 300 species and is grouped within the class Cephalopoda with squids, cuttlefish, and nautiloids. Like oth ...

es and the

vampire squid The vampire squid (''Vampyroteuthis infernalis'', lit. 'vampire squid from hell') is a small cephalopod found throughout temperate and tropical oceans in extreme deep sea conditions. The vampire squid uses its bioluminescent organs and its unique ...

. All living members of Octopodiformes have eight

arms Arms or ARMS may refer to: *Arm or arms, the upper limbs of the body Arm, Arms, or ARMS may also refer to: People * Ida A. T. Arms (1856–1931), American missionary-educator, temperance leader Coat of arms or weapons *Armaments or weapons **Fi ...

, either lacking the two tentacles of squid (as is the case in octopuses) or modifying the tentacles into thin filaments (as in vampire squid). Octopodiformes is often considered the

crown group In phylogenetics, the crown group or crown assemblage is a collection of species composed of the living representatives of the collection, the most recent common ancestor of the collection, and all descendants of the most recent common ancestor ...

of octopuses and vampire squids, including all descendants of their common ancestor. Some authors use the term Vampyropoda for the same general category, though others use "Vampyropoda" to refer to the

total group In phylogenetics, the crown group or crown assemblage is a collection of species composed of the living representatives of the collection, the most recent common ancestor of the collection, and all descendants of the most recent common ancestor. ...

(all cephalopods closer to octopods than to true squid). Another term is Octobrachia, referring to cephalopods without prominent tentacles. It is considered one of the two extant groups of the

Neocoleoidea Neocoleoidea is a large group of marine cephalopods. This cohort contains two extant groups: Decapodiformes (squid, cuttlefish, and relatives) and Octopodiformes (octopuses and the vampire squid). Species within this group exist in all major ...

. '' Pohlsepia'', originally described as earliest octopod is considered as dubious for this group in later study. ''Syllipsimopodi'', a squid-like cephalopod from the Mississippian-age Bear Gulch Lagerstätte of

Montana Montana ( ) is a landlocked U.S. state, state in the Mountain states, Mountain West subregion of the Western United States. It is bordered by Idaho to the west, North Dakota to the east, South Dakota to the southeast, Wyoming to the south, an ...

, was originally described as the oldest unambiguous vampyropod. However, further analyses might be necessary to unequivocally assign this cephalopod to Vampyropoda. ''Syllipsimopodi'' has a combination of squid-like features (like 10 arms) and octopod-like features (like biserial suckers and a simplified internal shell).

Classification

*Class

Cephalopoda A cephalopod is any member of the molluscan class Cephalopoda ( Greek plural , ; "head-feet") such as a squid, octopus, cuttlefish, or nautilus. These exclusively marine animals are characterized by bilateral body symmetry, a prominent head, ...

**Subclass

Nautiloidea Nautiloids are a group of cephalopods (Mollusca) which originated in the Late Cambrian and are represented today by the living ''Nautilus'' and ''Allonautilus''. Fossil nautiloids are diverse and species rich, with over 2,500 recorded species. Th ...

: nautilus **Subclass †

Ammonoidea Ammonoids are extinct, (typically) coiled-shelled cephalopods comprising the subclass Ammonoidea. They are more closely related to living octopuses, squid, and cuttlefish (which comprise the clade Coleoidea) than they are to nautiluses (family N ...

: ammonites **Subclass

***Superorder

Decapodiformes Decapodiformes is a superorder of Cephalopoda comprising all cephalopod species with ten limbs, specifically eight short arms and two long tentacles. It is hypothesized that the ancestral coleoid had five identical pairs of limbs, and that one ...

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 ...

cuttlefish Cuttlefish, or cuttles, are Marine (ocean), marine Mollusca, molluscs of the order (biology), suborder Sepiina. They belong to the class (biology), class Cephalopoda which also includes squid, octopuses, and nautiluses. Cuttlefish have a unique ...

***Clade Vampyropoda ****Genus †''

Syllipsimopodi ''Syllipsimopodi'' is an extinct member of the cephalopod Subclass (taxonomy), subclass Coleoidea originally interpreted to belong to the clade Vampyropoda, which includes Octopus, octopuses (Octopoda) and Vampyromorphida, vampire squids (Vampyro ...

'' ****Genus †'' Proteroctopus'' ****Superorder Octopodiformes / Octobrachia *****Family † Trachyteuthididae (''

incertae sedis or is a term used for a taxonomy (biology), taxonomic group where its broader relationships are unknown or undefined. Alternatively, such groups are frequently referred to as "enigmatic taxa". In the system of open nomenclature, uncertainty ...

'') *****Order

Vampyromorphida Vampyromorphida is an order of cephalopods comprising one known extant species ('' Vampyroteuthis infernalis'') and many extinct taxa. Physically, they somewhat resemble octopuses (their closest relatives), but are often called vampire squid ...

: vampire squid *****Clade: Muensterelloidea ******Family: † Muensterellidae ******Family: † Patelloctopodidae ******Order Octopoda ******* Genus †'' Keuppia'' (''

'') ******* Genus †''

Palaeoctopus ''Palaeoctopus'' is an extinct genus of octopuses that lived during the Late Cretaceous. It contains one valid species, ''P. newboldi'', which has been found in Lebanon. Taxonomy ''Calais newboldi'' was named by Henry B. Woodward in 1896 for ...

'' (''

'') ******* Genus †'' Paleocirroteuthis'' (''

'') ******* Genus †'' Proteroctopus'' (''

'') ******* Genus †'' Styletoctopus'' (''

'') *******Suborder

Cirrina Cirrina or Cirrata is a suborder and one of the two main divisions of octopuses. Cirrate octopuses have a small, internal shell and two fins on their head, while their sister suborder Incirrina has neither. The fins of cirrate octopods are ass ...

: finned deep-sea octopus ********Family Opisthoteuthidae: umbrella octopus ********Family Cirroteuthidae ********Family Stauroteuthidae *******Suborder

Incirrina Incirrata (or Incirrina) is a suborder of the order Octopoda. The suborder contains the classic " benthic octopuses," as well as many pelagic octopus families, including the paper nautiluses. The incirrate octopuses are distinguished from th ...

********Superfamily

Octopodoidea Octopodoidea is a Family (biology), superfamily of the Order (biology), suborder Incirrata containing all extant octopods except for the Cirrina, cirrate octopodes, Argonaut (animal), argonauts (Seven-arm octopus, Alloposidae, Argonautidae, ...

********* Family

Amphitretidae Amphitretidae is a Family (biology), family of mesopelagic octopods which contains three subfamily, subfamilies, formerly classified as families in their own right. It is classified in the Superfamily (taxonomy), superfamily Octopodoidea. Species ...

********** subfamily Amphitretinae: telescope octopus ********** subfamily

Bolitaeninae The Bolitaeninae are a subfamily, in the Family (biology), family Amphitretidae, of small, common pelagic zone, pelagic octopuses found in all tropical and temperate oceans of the world. The Taxonomy (biology), taxonomy of this taxon is not entir ...

: gelatinous octopus ********** subfamily Vitreledonellinae ********* Family

Bathypolypodidae ''Bathypolypus'' is a genus of octopuses in the monotypic family Bathypolypodidae. Species Species in the genus ''Bathypolypus'' include: * '' Bathypolypus arcticus'' ( Prosch, 1847) ** '' Bathypolypus arcticus arcticus'' – spoonarm octopu ...

********* Family

Eledonidae ''Eledone'' is a genus of octopuses forming the only genus in the family Eledonidae. It is mainly distributed in the northern and southern Atlantic Ocean, with one species, '' E. palari'', described from the southwestern Pacific Ocean and eastern ...

********* Family

Enteroctopodidae Enteroctopodidae is a small family of octopuses. This family was formerly considered a subfamily of the family Octopodidae ''sensu lato'' but this family has now been divided into a number of separate families with Enteroctopodidae as one of them ...

********* Family

Megaleledonidae Megaleledonidae is a family of octopuses in the superfamily Octopodoidea. It was formerly placed in the family Octopodidae ''sensu lato'' as the subfamily Megaleledoninae but more recent studies have raised this taxon as a valid family. Megalel ...

*********Family Bolitaenidae: gelatinous octopus *********Family

Octopodidae The Octopodidae comprise the family containing the majority of known octopus species (about 175 species). Genera The World Register of Marine Species lists these 23 genera: *'' Abdopus'' Norman & Finn, 2001 (7 species) *'' Ameloctopus'' Norman, ...

: benthic octopus ********Superfamily

Argonautoidea Argonautoidea is a superfamily of the suborder Incirrata containing all known argonautoids. Classification *Class Cephalopoda **Subclass Nautiloidea: nautiluses **Subclass †Ammonoidea: ammonites **Subclass Coleoidea ***Superorder Decapodif ...

*********Family Alloposidae: seven-arm octopus *********Family

Argonautidae The Argonautidae are a family of pelagic cephalopods that inhabit tropical and temperate oceans of the world. The family encompasses the modern paper nautiluses of the genus '' Argonauta'' along with several extinct genera of shelled octopo ...

: argonauts *********Family

Ocythoidae ''Ocythoe tuberculata'', also known as the tuberculate pelagic octopus or football octopus, is a pelagic octopus. It is the only known species in the family Ocythoidae. ''Ocythoe tuberculata'' is found in warm and temperate seas, especially ...

: tuberculate pelagic octopus *********Family Tremoctopodidae: blanket octopus

References

External links

Tree of Life web project: Octopodiformes
Neocoleoidea Protostome superorders Extant Pennsylvanian first appearances {{cephalopod-stub