Pinna nobilis, common name the "noble pen shell" or "fan mussel" is a species of large saltwater clam, a marine bivalve mollusc in the family Pinnidae, the 'pen shells'. It reaches up to 120 cm of shell length.
The bivalve shell is usually 91 cm (3 feet) long, and its shape differs depending on the region it enhabitates. Like all pen shells it is relatively fragile to pollution and shell damage. It attaches itself to rocks using a strong byssus composed of many silk-like threads which used to be made into cloth. These keratin fibres that the animal secretes by byssus gland are even 6 cm long. The inside of the shell is lined with brilliant mother-of-pearl.
species is the origin of sea silk, which was made from the byssus of the animal.
Unfortunately, in recent years, Pinna nobilis has become threatened with extinction, partly due to its prohibited fishing, the fact that the soft parts are edible, incidental killing by trawling and anchoring and also because of the decline in seagrass fields. Increasing pollution still causes destruction of eggs, larvae and adult mussels by chemicals.
As a consequence, the noble pen shell has been listed as an endangered species in the Mediterranean Sea. European Council Habitats Directive 92/43/EEC states on conservation of natural habitats and the wild fauna and flora that P. nobilis is strictly protected (by the Annex IV of EEC, 1992), all forms of deliberate capture or killing of fan mussel specimens are prohibited by law.
As part of the Costa Concordia disaster recovery effort ongoing in Italy (2012), a group of Pinna nobilis numbering about 200 was manually relocated to a nearby area, the reason for it being subsequent engineering work that might have caused harm to the species.
Text source: Wikipedia
Pinna (Pinna) nobilis Linnaeus, 1758
Pinna aculeatosquamosa Martens, 1866
Pinna cornuformis Nardo, 1847
Pinna ensiformis Monterosato, 1884
Pinna gigas Röding, 1798
Pinna incurvata Born, 1778
Pinna nigella Gregorio, 1885
Pinna nobilis var. aequilatera Weinkauff, 1867
Pinna nobilis var. inaequilatera Weinkauff, 1867
Pinna obeliscus Martens, 1866
Pinna squamosa Gmelin, 1791
Classification: Biota > Animalia (Kingdom) > Mollusca (Phylum) > Bivalvia (Class) > Pteriomorphia (Subclass) > Ostreida (Order) > Pinnoidea (Superfamily) > Pinnidae (Family) > Pinna (Genus) > Pinna nobilis (Species)