At first glance appears to be a red anemone, but closer inspection reveals it to be the colonial syphonophore rhodalid - with white gas bladder on top.

Image ID: expl2418, Voyage To Inner Space - Exploring the Seas With NOAA Collect
Photo Date: 2005 September 1.
Credit: North Atlantic Stepping Stones Science Party, IFE, URI-IAO; NOAA/OAR/OER

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