[Nematodes parasitizing fishes from Termas de Rio Hondo Pond, Santiago del Estero, Argentina]

Cucullanus pinnai and Spinitectus jamundensis are cited parasitizing three freshwater fish species: Pimelodus albicans, Leporinus obtusidens and Prochilodus lineatus, captured in Termas de Río Hondo pond, province of Santiago del Estero, Argentina, in 1992 and 1995. The three fish species were parasited by S. jamundensis, but C. pinnai was found only in P. albicans and L. obtusidens. Morphologic and morphometric parasitological studies were carried out. The specimens described were drawned. In addition, the following parasitic infection indexes were calculated: prevalence, mean and maximum intensity. The two nematode species identified are described for the first time in Argentina and increased the host range cited for the parasite species studied in this work.