The distribution of octopuses of Graneledone (Cephalopoda : Octopodidae) in reference to deep-sea features

Although deep-sea hydrothermal vents are renowned for having many apparentl y endemic taxa, normal deep-sea taxa also occur at vents. These opportunist ic taxa have been hypothesized to tolerate these physiologically stressful habitats due to pre-adaptation to low oxygen conditions. Octopuses of the d eep-sea genus Graneledone, likely a monophyletic group, appear to be one su ch taxon as they occur at several East Pacific hydrothermal vents. To furth er our knowledge of this genus and of other taxa opportunistic at chemosynt hetic habitats, collection localities of these octopuses north of 40 degree sS were verified and whether features such as vents, cold seeps, tectonic a ctivity or hydrocarbon deposits were present near the collection localities was determined. Hydrothermal vents, cold seeps or hydrocarbon deposits lie within one degre e of 17 of the 24 localities confirmed north of 40 degreesS. This distribut ion suggests that the octopuses routinely occur in low oxygen habitats, pot entially due to a pre-adaptation, a hypothesis that will require a species- level phylogeny for the genus. Low oxygen habitats offer opportunists incre ased prey biomass and possibly reduced predation rates. In addition, severa l of these areas offer hard substrata essential for egg attachment and broo ding by females of Graneledone.