Black sea rod

''Plexaura homomalla'', commonly known as the black sea rod or Caribbean sea whip, is a species of gorgonian-type octocoral in the family Plexauridae. It is widely distributed in the Caribbean from the Florida Keys to the northern coast of Venezuela. ''P. Homomalla'' contains the bioactive lipid Prostaglandin A2 15-acetate methyl ester at approximately 3% of total wet weight.