''Enteroctopus'' is an

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 ...

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 ...

whose members are sometimes known as giant octopuses.

Etymology

The generic name ''Enteroctopus'' was created by Alphonse Tremeau de Rochebrune and

Jules François Mabille Jules François Mabille (Tours, 5 December 1831 − 18 January 1904) was a French malacologist, biologist and zoologist who in many trips around the world discovered and studied many species of mollusc. In 1882−83 Mabille participated in the F ...

in 1887 and published in 1889, joining

Ancient Greek Ancient Greek (, ; ) includes the forms of the Greek language used in ancient Greece and the classical antiquity, ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek (), Greek ...

'gut' and , thus 'octopus ith arms similar toguts.'

Description

''Enteroctopus'' is a genus of generally temperate

es. Members of this genus are characterized by their large size and are often known as giant octopuses. ''Enteroctopus'' species have distinct longitudinal wrinkles or folds dorsally and laterally on their bodies. Their heads are distinctly narrower than the mantle width. The

hectocotylus A hectocotylus (: hectocotyli) is one of the arms of male cephalopods that is specialized to store and transfer spermatophores to the female. Structurally, hectocotyli are muscular hydrostats. Depending on the species, the male may use it merel ...

of the males in this genus, found on the third right arm, is long and narrow in comparison with other genera in the 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, ...

, often comprising one-fifth the length of the arm. Octopuses in this genus have large, paddle-like

papilla Papilla (Latin, 'nipple') or papillae may refer to: In animals * Papilla (fish anatomy), in the mouth of fish * Papilla (worms), small bumps on the surface of certain worms * Basilar papilla, a sensory organ of lizards, amphibians and fish * ...

e instead of the more conical papillae in other octopus genera.

Species

Genus ''Enteroctopus'' at present consists of four species, tabulated below:

Type species

''E. membranaceus'' has often been regarded as

type species In International_Code_of_Zoological_Nomenclature, zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the spe ...

of the genus, not because it was designated as such by Rochebrune and Mabille when they erected the genus, but because it was the first named species in the genus. Robson in his 1929 monograph of octopods regarded ''E. membranaceus'' as a '' species dubium'' because the original description was insufficient to identify an individual species, the

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 ...

was an immature specimen, and the type specimen no longer existed. As such, the genus was considered invalid until Hochberg resurrected it in 1998. Hochberg noted that Robson had considered ''E. membranaceus'' a

junior synonym In taxonomy, the scientific classification of living organisms, a synonym is an alternative scientific name for the accepted scientific name of a taxon. The botanical and zoological codes of nomenclature treat the concept of synonymy differently. ...

of '' E. megalocyathus'', the second species assigned to the genus by Rochebrune and Mabille in their 1889 description. Additionally, since Rochebrune and Mabille did not actually assign type status to ''E. membranaceus'', Hochberg concluded that ''Enteroctopus'' was indeed a valid genus and transferred type-species status to ''E. megalocyathus'' based on his conclusion that ''E. megalocyathus'' and ''E. membranaceus'' are the same species.

Distribution

Species in the genus ''Enteroctopus'' are restricted to the temperate areas of the Northern and Southern Hemispheres. ''E. dofleini'' is the only member of the genus found in the Northern Hemisphere, and also the most widely distributed: It is found from

Southern California Southern California (commonly shortened to SoCal) is a geographic and Cultural area, cultural List of regions of California, region that generally comprises the southern portion of the U.S. state of California. Its densely populated coastal reg ...

, along the North Pacific Rim to

Japan Japan is an island country in East Asia. Located in the Pacific Ocean off the northeast coast of the Asia, Asian mainland, it is bordered on the west by the Sea of Japan and extends from the Sea of Okhotsk in the north to the East China Sea ...

, including the

Okhotsk Okhotsk ( rus, Охотск, p=ɐˈxotsk) is an urban locality (a work settlement) and the administrative center of Okhotsky District of Khabarovsk Krai, Russia, located at the mouth of the Okhota River on the Sea of Okhotsk. Population: ...

and

Bering Sea The Bering Sea ( , ; rus, Бе́рингово мо́ре, r=Béringovo móre, p=ˈbʲerʲɪnɡəvə ˈmorʲe) is a marginal sea of the Northern Pacific Ocean. It forms, along with the Bering Strait, the divide between the two largest landmasse ...

s. The other three species are found in the Southern Hemisphere; ''E. megalocyathus'' occurs on the southeastern coast of

South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a considerably smaller portion in the Northern Hemisphere. It can also be described as the southern Subregion#Americas, subregion o ...

, ''E. magnificus'' on the southwestern coast of

Africa Africa is the world's second-largest and second-most populous continent after Asia. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 20% of Earth's land area and 6% of its total surfac ...

from

Namibia Namibia, officially the Republic of Namibia, is a country on the west coast of Southern Africa. Its borders include the Atlantic Ocean to the west, Angola and Zambia to the north, Botswana to the east and South Africa to the south; in the no ...

Port Elizabeth Gqeberha ( , ), formerly named Port Elizabeth, and colloquially referred to as P.E., is a major seaport and the most populous city in the Eastern Cape province of South Africa. It is the seat of the Nelson Mandela Bay Metropolitan Municipal ...

South Africa South Africa, officially the Republic of South Africa (RSA), is the Southern Africa, southernmost country in Africa. Its Provinces of South Africa, nine provinces are bounded to the south by of coastline that stretches along the Atlantic O ...

, and ''E. zealandicus'' in temperate

New Zealand New Zealand () is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and List of islands of New Zealand, over 600 smaller islands. It is the List of isla ...

Size

The member of this genus that best embodies the common name "giant octopus" is ''

Enteroctopus dofleini The giant Pacific octopus (''Enteroctopus dofleini''), also known as the North Pacific giant octopus, is a large marine cephalopod belonging to the genus '' Enteroctopus'' and Enteroctopodidae family. Its spatial distribution encompasses much o ...

'', which holds the record of being the world's largest octopus based on direct measurements of a individual, weighed live. This octopus had a total length near to . The remaining members of the genus are substantially smaller, with ''E. megalocyathus'' having an average mass of and reaching a total length of . ''E. magnificus'' reaches a total length of around .

Footnotes

References

{{Authority control Enteroctopodidae Taxa named by Alphonse Trémeau de Rochebrune Taxa named by Jules François Mabille