''Argonauta bottgeri'', also known as Böttger's argonaut, is a
species
In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriat ...
of
pelagic
The pelagic zone consists of the water column of the open ocean, and can be further divided into regions by depth (as illustrated on the right). The word ''pelagic'' is derived . The pelagic zone can be thought of as an imaginary cylinder or w ...
octopus
An octopus ( : octopuses or octopodes, see below for variants) 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, ...
belonging to the
genus
Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nom ...
''
Argonauta''. The female of the species, like all
argonaut
The Argonauts (; Ancient Greek: ) were a band of heroes in Greek mythology, who in the years before the Trojan War (around 1300 BC) accompanied Jason to Colchis in his quest to find the Golden Fleece. Their name comes from their ship, ''Argo'', n ...
s, creates a paper-thin eggcase that coils around the octopus much like the way a nautilus lives in its shell (hence the name
paper nautilus
The argonauts (genus ''Argonauta'', the only extant genus in the family Argonautidae) are a group of pelagic octopuses. They are also called paper nautili, referring to the paper-thin eggcase that females secrete. This structure lacks the gas-f ...
).
''A. bottgeri'' is the smallest argonaut species. The eggcase rarely exceeds 50 mm in diameter, although exceptional specimens have been known to grow up to 67.0 mm. ''A. bottgeri'' is similar to ''
Argonauta hians'', but differs in having more pronounced ribs and prominent
tubercle
In anatomy, a tubercle (literally 'small tuber', Latin for 'lump') is any round nodule, small eminence, or warty outgrowth found on external or internal organs of a plant or an animal.
In plants
A tubercle is generally a wart-like projection ...
s on the keel. The eggcase does not have winged protrusions as is sometimes the case with ''A. hians''. It is generally darker than that of any other species, ranging in colour from ochre-yellow to almost black, although completely white specimens have been reported from
South Africa
South Africa, officially the Republic of South Africa (RSA), is the southernmost country in Africa. It is bounded to the south by of coastline that stretch along the South Atlantic and Indian Oceans; to the north by the neighbouring coun ...
n waters. The eggcase is finely granulated and normally lacks the porcelain-like shine of other species.
''A. bottgeri'' is best known from the waters off southern and eastern
Africa
Africa is the world's second-largest and second-most populous continent, after Asia in both cases. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 6% of Earth's total surface area ...
, although it has also been reported from other parts of the
Indian Ocean
The Indian Ocean is the third-largest of the world's five oceanic divisions, covering or ~19.8% of the water on Earth's surface. It is bounded by Asia to the north, Africa to the west and Australia to the east. To the south it is bounded by ...
and from the western
Pacific Ocean
The Pacific Ocean is the largest and deepest of Earth's five oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean (or, depending on definition, to Antarctica) in the south, and is bounded by the continen ...
. The ''