Prevalence of Mytilicola intestinalis (Copepoda: Mytilicolidae) and Urastoma cyprinae (Turbellaria: Hypotrichinidae) in marketable mussels Mytilus galloprovincialis in Italy.

Abstract Marketable mussels Mytilus galloprovincialis traded with commercial certification from production sites in Italy and abroad (France, Spain) were examined for the presence of Mytilicola intestinalis (Copepoda: Mytilicolidae) and Urastoma cyprinae (Turbellaria: Hypotrichinidae) from October 1994 to February 1996. The prevalence of M. intestinalis was 4.1% and 4.7% respectively in mussels from Lerici (La Spezia) and S. Pietro in Volta (Venice), whereas it rose to 57.9% in the samples from Spain. M. intestinalis was absent in mussels from Chioggia (Venice), Ganzirri (Messina), Taranto, Trieste and France. The prevalence of U. cyprinae varied considerably, ranging from 0.3% in mussels from Trani (Bari) to 33.2% and 86.3% respectively in those from Chioggia and Trieste. It was 85.7% in samples from France and 63.7% in those from Spain.