Most of the world’s comb jellies are planktonic with a lesser percentage (roughly one-third) living as benthic species, meaning they live on the ocean bottom. Of these bottom-dwelling species, a number grow on octocorals. However, up until a recent report in the journal Coral Reefs, none have been observed growing on scleractinian corals like Fungia spp.
In their report “Out of sight: aggregations of epizoic comb jellies underneath mushroom corals,” researchers Hoeksema, Waheed, Alamaru report on this interesting finding.
This association was discovered in June 2013 during a biodiversity survey around Payar Island, Strait of Malacca, Malaysia. Large aggregations of these benthic comb jellies were discovered at about 9-12 meters in depth on the underside of many free-living mushroom corals, which included both Pleuractis moluccensis and Fungia fungites.
The authors note that similar associations were also found with other fungiids including Ctenactis echinata, Cycloseris costulata, Herpolitha limax, and Lithophyllon repanda in Eilat (Israel), Sabah (Malaysia), and South Sulawesi (Indonesia).