BIODIVERSITY OF FUCALES IN THE USTICA ISLAND MARINE PROTECTED AREAS (TYRRHENIAN SEA, ITALY)

Fucales (Phaeophyceae) are ecosystem engineers and forest-forming macroalgae that are among the most productive and valuable carbon-rich marine benthic communities. In the Mediterranean, the predominant species belong to the genera Cystoseira sensu lato (s.l.) (i.e., Cystoseira sensu stricto, Ericaria, and Gongolaria) and Sargassum C. Agardh, which provide a number of important ecosystem functions and services. Increasing human threats and warming are affecting the species distribution, genetic diversity, functional responses and interactions of these valuable and vulnerable communities. In recent decades, populations of Cystoseira s.l. have significantly reduced their range. Therefore, there is an urgent need to assess the current distribution of the species, especially in MPAs, which play a fundamental role in valorization and conservation of these communities. We present here an assessment of the occurrence and distribution of Fucales in the Ustica Island MPA (Tyrrhenian Sea, Italy), inferred from literature data. A high diversity was found, with 21 taxa of the complex Cystoseira sensu lato and 4 taxa of the genus Sargassum. The data presented here provide a necessary basis for the MPA to plan future monitoring activities and to record changes (expansion, regression and/or loss) in these valuable communities.