Six new records of hydromedusae are reported as secondary hosts of Opechona sp. (Lepocreadiidae) for the Brazilian coast. Among the 392 hydromedusae sampled, 43 (~11%) were harbouring metacercaria. Prevalence (P) and intensity of infection (I) of Opechona sp. varied considerably among the different host species. Gossea brachymera (Limnomedusae) was highly parasitized (P = 30%; I = 1–7), while the other five hydromedusae species were not (P = 1.5–10; I = 1–2). The high parasitism in G. brachymera suggests the importance of this species in the transmission of Opechona sp. to fish, the definitive hosts, and highlights the hydromedusae as a probable noteworthy food item for zooplanktivorous fish in the area.
