Parasitisms (Trematoda, Digenea) in medusae from the southwestern Atlantic Ocean: Medusa hosts, parasite prevalences and some ecological implications.

DIAZ BRIZ L.; MARTORELLI S; GENZANO G. N.; MIANZAN H.

HYDROBIOLOGIA

SPRINGER

Lugar: Berlin; Año: 2012 vol. 690 p. 215 - 226

0018-8158

Digenean are important endoparasites of fish with complex life cycles; some genera includemedusae as secondary hosts. Their transmission to fish occurs when fish prey on these jelly hosts. Fish predation on jellyfish is a widespread phenomenon, even though predation by fish on jellyfish has not been determined through parasitism yet. We hypothesized that medusae with high prevalences of digeneans could be important for their transmission to fish. Atotal of 48,900 specimens of 50 medusa species were analyzed; 2,181 harbored digeneans. Opechona sp.and Monascus filiformis were the most frequent and abundant parasites with the widest range of hosts. Hemiuridae gen. sp. and Bacciger sp. were found in few specimens of some medusa species. Prevalences were unevenly distributed in the region. Three groups with high prevalence values were identified mainly related to frontal areas: Rı´o de la Plata, Bahı´a Blanca, and North Patagonian tidal front. Eucheilota ventricularis, Clytia hemisphaerica, Proboscidactyla mutabilis,Liriope tetraphylla, and Aequoerea spp. were the medusae that contributed the most as secondary hosts to M. filiformis and Opechona sp. The high prevalences found in these medusae suggest that may be a fundamental part of the life cycles of both parasites in these areas.