A closer view doesn't help much. Perhaps it is a red jelly being eaten by ananemone with translucent tentacles and the jelly is completing covering thecentral portion of the anemone.
4/10/2019 1:11:14 PM
Date: 20150416T172620Z
Credit: NOAA OKEANOS EXPLORER Program, Oceano Profundo 2015; Exploring Puerto Rico's Seamounts, Trenches, and Troughs
Location: Puerto Rico, Guayanilla Canyon East Wall