[New metacercariae of the genus Tylodelphys (Trematoda, Diplostomatidae) in lacustrine populations of Galaxias maculatus (Teleostei, Galaxiidae)].

Metacercariae of three new species of Tylodelphys (Trematoda, Diplostomatidae) were found in the brain of Galaxias maculatus (Teleostei, Galaxiidae), at the Meliquina Lake, Neuquen Province, Argentina. These metacercariae are morphologically described as Tylodelphys argentinus n. sp., Tylodelphys barilochensis n. sp. and Tylodelphys crubensis n. sp. This is the first time that a stage of genus Tylodelphys is mentioned parasitizing Galaxias maculatus. Metacercariae of T. barilochen sis n. sp. were also found in G. maculatus brain at the Perito Moreno Lake, Rio Negro Province, Argentina.