Larval digeneans in Biomphalaria snails from the Salto Grande Dam in the Uruguay river

Abstract

We report and describe larval digenean infections in Biomphalaria tenagophila and Biomphalaria straminea snails from Salto Grande Dam area, on the Argentinean and Uruguayan coasts of the Uruguay river. Both species of snail have been reported in Brazil, near the study site, as vectors of Schistosoma mansoni. From 1989 to 1992, we dissected 1,632 B. tenagophila and 311 B. straminea specimens. Though we did not find S. mansoni, we found 19 larvae (cercariae and metacercariae) infecting the snails. We describe cercariae of the families Echinostomatidae (4), Notocotylidae (1), Plagiorchiidae or Telorchiidae (1), Clinostomidae (1), Paramphistomidae (1), Strigeidae or Diplostomidae (4), Strigeidae (1), and Schistosomatidae (3); and metacercarial cysts of the families Strigeidae (1) and Echinostomatidae (2).