The functional relevance of oxygen transport by hemocyanin of the Antarctic octopod Megaleledone senoi and of the eurythermal cuttlefish Sepia officinalis was analyzed by continuous and simultaneous recordings of changes in pH and hemocyanin oxygen saturation in whole blood at various temperatures. These data were compared to literature data on other temperate and cold-water cephalopods (octopo...

The emission of blue-green bioluminescence ({lambda}max = 470 nm) was observed from sucker-like structures arranged along the length of the arms of the cirrate octopod Stauroteuthis syrtensis. Individual photophores either glowed dimly and continuously or flashed on and off more brightly with a period of 1-2 seconds. Examination of the anatomy and ultrastructure of the photophores confirmed tha...

Immature octopods (Tremoctopus violaceus) have been found with numerous fragments of tentacles of the coelenterate Physalia attached to the suckers of their dorsal arms. The probable method of acquisition, the evidence of adaptation for holding the tentacles, and the possibility that the octopod uses these coelenterate tentacles as offensive and defensive weapons are discussed.

Figure 1. The ‘Kraken’ myth. Ancient tales repeatedly reported octopod-like sea-monsters attacking sea vessels. Indeed, octopuses may reach a maximum of 3 m body size, but the foundation of these ancient tales is based on giant squids (with ten rather than eight arms as depicted here) defending itself against its main predator, a sperm whale, rather than octopuses. Squids are known to leave suc...

East Antarctic octopods were identified by sequencing mtCOI and using four analytical approaches: Neighbor-joining by Kimura-2-Parameter-based distances, character-based, BLAST, and Bayesian Inference of Phylogeny. Although the distance-based analytical approaches identified a high proportion of the sequences (99.5% to genus and 88.1% to species level), these results are undermined by the absen...