Pinna nobilis is the largest bivalve in the Mediterranean, reaching 120 cm, with a triangular shell planted vertically in Posidonia seagrass and anchored by a byssus. Since 2016, a massive epidemic caused by the parasite Haplosporidium pinnae has driven near-extinction across much of the Mediterranean. Classified Critically Endangered. Mediterranean endemic, symbol of seagrass meadows, strictly protected.

