Wow! What a beauty!
This spectacular vision is a deep sea octopus from the suborder cirrata.
Cirrate octopods have three main things that distinguish them from those within the other, more familiar suborder called incirrata. They are: a small, internal shell, a pair of fins on the mantle, and cirri.
The cirri look like spikes on the arms and this octopus has particularly long, threatening ones. It looks like silk sheets crossed with a bed of nails. A most luxurious torture.
The video calls this one a Dumbo Octopus, which can work! Sure has the ears for it. However, I think of Dumbos as the little, squat ones in the genus Grimpoteuthis. This looks more like one of the big, long ones in Stauroteuthis.
Stauroteuthids have been found with tiny copepods in their gut so while no-one is quite sure, it seems they use those enormous cirri to create a current that ushers crustaceans right into their mouth. The cirri are actually fleshy and not hard as nails at all!
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