CONICET | Buscador de Institutos y Recursos Humanos

In the last 20 years jellyfish have beenrevalorized as important food items of marine fish. In this context, itsimportance as intermediate host of digeneans has increased. Since the 90s Ihave been examined jellyfish for parasites mainly in the South West Atlanticand the Gulf of Mexico. During these years, more than 50,000 jellyfish wereexamined for parasites. Different metacercariae belonging Lepocreadiidae,Hemiuridae, Fellodistomidae and Baccigeridae were found in addition to larvalnematodes, metacestods, trichodinid ciliophorans andcrustaceans. Five life cycles were studied and now the barcodes of these larvalstages is beginning to be studied. Some changes in the relationshipdigeneans-jellyfish were observed probably associated with increases in thejellyfish blooms worldwide. At the moment were observed: 1-As the transmissionof parasites often depends on the host densities. During blooms certain parasites such as amphipods,anemones and digeneans can spread more easily in the population of jellyfishand then the prevalence may increase. 2-The parasites of jellyfish can havedeleterious effects on host populations. 3- There are still few studies thatevaluate the effects of jellyfish parasites on host populations over time.4-Prevalence values observed in the Gulf of Mexico and southwest Atlantic,contrast with the ideas of the helminth infections is low in the marinezooplankton due to the dilute nature of the pelagic environment. 5- carnivoroushabits of many jellyfish can transfer parasites among them 6- The presence ofmetacercariae encysted in some digeneans could indicate a change in thehost-parasite relationship.