Possible Population Growth of Astrospartus mediterraneus (Risso, 1826) (Ophiuroidea, Gorgonocephalidae) in the Mediterranean Sea

During the last decades, number of observations basket star Astrospartus mediterraneus (Risso, 1826) in Mediterranean Sea has significantly grown, thanks to SCUBA diver and ROV sightings, citizen reports, as well particularly large catches by artisanal fishery. Having been generally considered rare many areas basin, such a long-term increase records might assign this putative role winner species context climate changes. In present study, we combined overall literature information with data available for Ligurian collected during extensive campaigns conducted between 2012 2022 at depth ranging from 20 123 m, better understand distribution abundance species. The was observed almost whole explored bathymetric range living on gorgonians (Eunicella cavolini, E. verrucosa, Paramuricea clavata, Leptogorgia sarmentosa) massive sponges (Aplysina cavernicola, Sarcotragus foetidus, Spongia lamella, Axinella polypoides). period, recorded specimens did not show clear trend, but differences emerged over years months. These variations were strongly correlated rainfall amounts that, oligotrophic waters, those Sea, represent an important input organic matter these passive filter feeders, especially summertime.