''Macrotritopus'' is a poorly known genus of

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, cuttle ...

es in the family Octopodidae. As it stands, ''Macrotritopus'' contains one valid described species, ''

Macrotritopus defilippi ''Macrotritopus defilippi'', commonly known as the Lilliput longarm octopus or the Atlantic longarm octopus, is a small species of octopus, a marine cephalopod mollusc of the order Octopoda. This species occurs in the Atlantic Ocean, the Medite ...

''. Two poorly described, unresolved taxa which are known only from planktonic hatchlings have been tentively assigned ''

Macrotritopus equivocus ''Macrotritopus'' is a poorly known genus of octopuses in the family Octopodidae. As it stands, ''Macrotritopus'' contains one valid described species, ''Macrotritopus defilippi''. Two poorly described, unresolved taxa which are known only f ...

'' and '' M. scorpio'', as well as a further three undescribed

Indo-Pacific The Indo-Pacific is a vast biogeographic region of Earth. In a narrow sense, sometimes known as the Indo-West Pacific or Indo-Pacific Asia, it comprises the tropical waters of the Indian Ocean, the western and central Pacific Ocean, and the ...

species. ''Macrotritopus'' was originally described from a single juvenile specimen which was named ''Macrotritopus equivocus'' notable for having an elongated third arm. This specimen gave the name ''Macrotritopus'' larva to this form of

paralarva Paralarvae (singular: ''paralarva'') are young cephalopods in the planktonic stages between hatchling and subadult. This stage differs from the larval stage of animals that undergo true metamorphosis. Paralarvae have been observed only in membe ...

which was misidentified as the newly hatched juveniles of ''

Scaeurgus unicirrhus ''Scaeurgus'' is a genus of octopuses in the family Octopodidae. The species of this genus are characterized by inhabiting the upper bathyal benthic zone from temperate and tropical latitudes in all major oceans. Species * '' Scaeurgus jumeau'' ...

''. When the eggs of ''M. defilippi'', which were kept in captivity, hatched and the resultant larvae were observed to be of the ''Macrotritopus'' larval type then the juveniles were connected with the adults. This means that the type species of ''Macrotritopus'' is a juvenile and that ''M. defillipi'' is the only species where the adult form is known. The presence of ''Macrotritopus'' larvae” off South Africa and the Indo‑West Pacific from Australia to Hawaii indicates that there may be a number of yet to be described species within this genus.

Species

*''

'' ( Vérany, 1851) *''

'' ( Robson, 1929) (''

taxon inquirendum 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 term t ...

'', juvenile: identity unresolved) *'' Macrotritopus scorpio'' (

Berry A berry is a small, pulpy, and often edible fruit. Typically, berries are juicy, rounded, brightly colored, sweet, sour or tart, and do not have a stone or pit, although many pips or seeds may be present. Common examples are strawberries, raspb ...

, 1920) (''taxon inquirendum'', unresolved, potential name for West Atlantic "''defillipi''")

References

{{Taxonbar, from=Q18592031 Octopuses Cephalopod genera Taxa named by Georg Grimpe