Dumbo Octopus

Dumbo octopuses are the deepest-living octopuses known, named after Disney's Dumbo for the ear-like fins that flap on either side of the head.

They live singly on the deep sea floor, usually at 3000 to 4000m and ranging from 1000m down to hadal depths.

Rather than using jets of water, they swim with these fins, using the webbed arms to steer and saving energy as they go. The soft, gelatinous, semi-translucent body copes well with the crushing pressure.

Food is slowly hunted along the sea floor. Cirri along the arms sense movement, prey is trapped in the webbing, and it is then wafted to the mouth. With a beak that is underdeveloped or absent, dumbo octopuses swallow worms, snails and small crustaceans whole.

They have no ink sac, since a cloud of ink would be no use in the dark. Mates are rare down there, and females are ready for that: they can store sperm packets for long periods and carry eggs at several stages at once, laying hard-shelled eggs on rocks or corals.