''Graneledone yamana'' is a species 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 ...

in the genus ''

Graneledone ''Graneledone'' is a genus of octopuses in the family Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The pu ...

''. ''G. yamana'' is assigned to this genus because of the absence of an

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 ...

and crop, the presence of cartilaginous warts covering the body cavity, uniserial suckers on the

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 ...

, and a reduced

radula The radula (, ; plural radulae or radulas) is an anatomical structure used by molluscs for feeding, sometimes compared to a tongue. It is a minutely toothed, chitinous ribbon, which is typically used for scraping or cutting food before the food ...

. This genus has been found in the deep waters of the Atlantic Ocean near

hydrothermal vent A hydrothermal vent is a fissure on the seabed from which geothermally heated water discharges. They are commonly found near volcanically active places, areas where tectonic plates are moving apart at mid-ocean ridges, ocean basins, and hotspot ...

s. Its identifying characteristics are papillose skin, two horns located above the eyes, small gills, and five to seven lamellae located on the outside of the demibranch. The arms of ''G. yamana'' have 35–80 suckers on the females and 26–70 on the males. This species is known from the southwest Atlantic Ocean off the coasts of Uruguay, Argentina, and southern Brazil. ''G. yamana'' is the fifth species of ''Graneledone'' found in the southern oceans. ''G. yamana'' physically resembles the species ''

Graneledone verrucosa ''Graneledone'' is a genus of octopuses in the family Octopodidae. The type species is ''Eledone verrucosa'' Verrill, 1881. Species Species and subspecies within the genus ''Graneledone'' include:Norman M.D., Finn J.K. & Hochberg F.G. (2014). F ...

'', except the cartilaginous warts on the body cavities of both these species differ. ''G. verruscosa'' is also found in the North Atlantic Ocean instead of the South.Allcock A.L., Collins M.A., and Vecchione M. 2003. A redescription of ''Graneledone verrucosa'' (verril, 1881) (Octopoda:Octopodidae). J.Mollus. Stud. 69(2):135-143.

References

* Kommritz J. G. 2000. A new species of ''Graneledone'' (Cephalopoda:Octopodidae) from the southwest Atlantic Ocean. J.Mollus.Stud.66(4):5 43-549. * Allcock A.L., Collins M.A., and Vecchione M. 2003. A redescription of ''Graneledone verrucosa'' (Verrill, 1881) (Octopoda:Octopodidae). J.Mollus. Stud. 69(2):135-143. Octopodidae Molluscs described in 2000 {{octopus-stub