Fan Mussel

• conservaciónIt is one of the largest bivalve molluscs in the Mediterranean, and its populations have collapsed over the past decade because of a parasite that has caused mass mortality right across the sea.
• It is the largest bivalve endemic to the Mediterranean and one of the largest in the world: it reaches 120 cm.
• Since the autumn of 2016 it has suffered a mass mortality caused by the parasite Haplosporidium pinnae, with outbreaks reaching 100 % mortality within a few months. In 2019 it was moved to the Critically Endangered category.
• It is considered functionally extinct across most of its range: a survey of 800 km of Italian coast in 2022 did not find a single living individual.
• Its last refuges are brackish coastal lagoons. In the Thau lagoon, in southern France, a population of more than 100,000 individuals survives at densities of up to 511 animals per 100 m².
• Its byssus filaments were woven into sea silk, a legendary golden cloth that barely any craftswomen are still able to work.
• It is protected by the Barcelona Convention and by European legislation.

Skeleton type

Invertebrate - external calcareous bivalve shell (mollusc)

Habitat & environment

Posidonia meadows and soft Mediterranean bottoms between 0.5 and 60 m, anchored upright in the sediment by the narrow end of the shell; today its last healthy populations are in brackish lagoons

Sources consulted: https://en.wikipedia.org/wiki/Pinna_nobilis