Fatty acid composition of the tropical-subtropical starfish Aquilonastra yairi under ocean acidification and warming in the laboratory

Lipid-associated fatty acids (FAs) were determined in the tropical-subtropical starfish Aquilonastra yairi from the culture stock of the ZMT-MAREE laboratory in response to projected near-future global change. To investigate the physicochemical alteration of starfish induced by elevated seawater pCO2 and temperature, starfish of the species A. yairi (342 specimens, size 3-11 mm in diameter, culture stock) were reared in aquaria system under controlled experimental environment conditions at ZMT-MAREE. The starfish were acclimatized to two temperature levels (27 °C, 32 °C) crossed with three pCO2 concentrations (455 µatm, 1052 µatm, 2066 µatm). The fatty acids (FAs) of the starfish were determined as fatty acid methyl esters (FAMEs) in accordance with methods from Christie (1998). FA composition was unaffected by combined elevated temperature and pCO2, but at elevated temperature, there was an increase in saturated FAs (SFAs) and polyunsaturated FAs (PUFAs), and a decrease in monounsaturated FAs (MUFAs). Our results indicate that the lipid-associated biochemistry of A. yairi is resilient and capable of coping with near-future ocean acidification and warming.