Appears to be a coronate jellyfish with a single hypertrophied tentacleextending behind the open bell. Genus Atolla.
4/10/2019 1:11:13 PM
Date: 20150416T150654Z
Credit: NOAA OKEANOS EXPLORER Program, Oceano Profundo 2015; Exploring Puerto Rico's Seamounts, Trenches, and Troughs
Location: Puerto Rico, Guayanilla Canyon East Wall