Preliminary assessment of macrobenthic assemblages of coralligenous habitats across the Mediterranean Sea

International audience; A preliminary study of coralligenous benthic assemblages was performed in 2013 at 20 sites in Turkey, Greece and France within the framework of the EU-funded project CIGESMED. At each area the most conspicuous species were recorded using in situ observations and photoquadrats. The survey revealed a total of 267 species belonging to 11 systematic groups. Within the sampled sites, algae ranked first in terms of species richness (83 species), followed by Porifera (55 species), Cnidaria (32 species), Bryozoa (22 species) and Echinodermata (21 species). A total of 172 species were encountered in France, 107 species in Turkey and 93 species in Greece. Six alien species, Caulerpa cylindracea, Stypopodium schimperi, Acrothamnion preissii, Womersleyella setacea, Amphistegina lobifera and Synaptula reciprocans, were found at sampling sites. Taking into account the preliminary character of the performed surveys, the biodiversity reported herein is presumably underestimated. Species richness is expected to increase following the upcoming, more exhaustive CIGESMED surveys. The final species lists will later be critically evaluated to meet the needs for developing new biotic indices and also for applying already developed ones (e.g. Index-Cor) in order to be used by scientists, managers and stake holders for the effective monitoring and management of coralligenous communities.