mediterranean sea. large fragments of a valve of shell of pinna nobilis found on a beach in south-western sardinia

soil leaf wood rock wildlife tree plant nature autumn food produce geology flower trunk animal fungus grass invertebrate mediterranean sea large fragments valve shell pinna nobilis found beach south-western sardinia fan mussel noble pen habitat sulcis critically endangered species bivalve mollusc byssus animals italy iglesiente coast pinnidae family mother pearl marine environment coastal broken