First records of polyclads (Platyhelminthes, Polycladida) associated with Nodipecten nodosus (Linnaeus 1758) aquaculture.

Free-living marine Platyhelminthes of the order Polycladida are known to interact with molluscs, especially bivalves. The impact and damage of polyclads that feed on farmed oysters can be so significant that they are known as oyster leeches. The present contribution identifies three species of polyclads associated with scallop aquaculture at Ilha Grande, southeastern Brazil: one cotylean, Lurymare matarazzoi, and two acotyleans, Imogine tica and Imogine refertus. This is the first time these species are illustrated with photographs of live specimens and histological sections after their original description. This is also the first record of an association of polyclads with a pectinid mollusc. The ecological role of polyclads is still little known, and experiments are lacking. However, it shows that native flatworm species are interacting with Nodipecten nodosus in experimental aquaculture, feeding either on the molluscs or on the associated fauna. [ABSTRACT FROM AUTHOR]