Thus the aim of this study was to investigate the impact ofocean acidification on parameters of the immune system and inthe coelomic fluid pH of two echinoderm species Lytechinus varie-gatus and Echinometra lucunter at two different pH’s and at two different time periods (24 h and 5 days).
These specieswere chosen because they inhabit different tidal zones on the coast:L. variegatus inhabits zones deeper than 5 m and sandy soil, and andE. lucunter inhabits the rocky shore and is closer to the surfaceregularly being exposed to tidal variations.