Mass mortality of Pinna nobilis Linnaeus, 1758 (Mollusca, Bivalvia) in the Taranto and Tremiti Islands populations: citizen science to help scientists.

The mass mortality outbreak affecting Pinna nobilis populations, from Spanish Mediterranean coasts to Marmara Sea, was then observed in the Gulf of Taranto and at Tremiti Islands. In Taranto the mortality was discovered during the Summer 2018, while in the Tremiti Islands a dramatic mass mortality occurred at the end of the Summer 2019. Cytology, histopathology and molecular diagnosis revealed the presence in Taranto and Tremiti populations of two species of Mycobacterium Aronson and of Haplosporidium pinnae, described in previous reports. Citizen Science campaigns were launched to support the work of researchers in monitoring the populations of this critically endangered species. The contribution of citizen science has proven to be effective in the fast detection of the mortality event. Now, the monitoring of survived specimens of P. nobilis is urgently needed to further understand the pathology spreading pathway and to plan protection strategies.