Survey of mycosporine-like amino acids in different morphotypes of the coral Galaxea fascicularis from Okinawa, Japan

The coral Galaxea fascicularis exhibits marked variation in polyp color and several color morphs have been described (e.g. brown polyp with green oral disc, BG; brown with green septal tentacles, Gs; brown with white fluorescent tentacles, Wt). Color morphs of sessile marine inver tebrate species may exhibit considerable differences in their capacity to absorb UV radiation, al­ though only a few studies have examined intra­species variation in the UV­absorbing com pounds, mycosporine­ like amino acids (MAAs). The objective of this study was to investigate possible differences in the composi­ tion and quantity of MAAs in the coral tissue and symbio­ tic algae of several G. fascicularis color morphs. Marked differences in the composition and quantity of MAAs were found between the BG and Gs/Wt morphs of G. fascicularis, both in the coral tissue and freshly isolated symbiotic algae. Future studies, especially genetic analy­ ses of corals and their symbionts, are necessary to un­ derstand whether these observed differences in the com­ position and quantity of MAAs reflect phylogenetic or bio geographical differences among the corals.