CONICET | Buscador de Institutos y Recursos Humanos

A parasitological survey of teleosts and elasmobranchs along the coast of Argentina yielded a total of 11 species of trypanorhynchs. Most of them were recovered for the first time in the southwestern Atlantic. Adult trypanorhynchs were represented by Eutetrarhynchidae (i.e. Dollfusiella vooremi, Dollfusiella taminii, Parachristianella damiani, Dollfusiella n. sp., and Mecistobothrium n. sp.), Lacistorhynchidae (i.e. Grillotia carvajalregorum and Grillotia patagonica), and Tentaculariidae (i.e. Heteronybelinia mattisi). The eutetrarhynchids were found in arhynchobatid skates, myliobatiform eagle rays and carcharhinid sharks. The tentaculariids are parasites of arhynchobatid skates, and the lacistorhynchids were found in squatiniforms and arhynchobatids. Tentaculariid pleroceroids include at least 2 species of teleosts (ophidiiforms or perciforms) in their life cycle. Among lacistorhynchids, plerocerci of G. carvajalregorum were found in at least 17 species of unrelated teleosts, whereas plerocerci of G. patagonica were registered in 5 species of teleosts (perciforms and gadiforms). All adults, with the exception of Dollfusiella n. sp., are highly specific for their definitive host. In contrast, all larval stages, plerocerci or plerocercoids, show a low specificity for their intermediate host. The low diversity of tentaculariids in the Argentine Sea might be due to very few sharks examined comparing to batoids, as they are common hosts for this group of cestodes. Considering that this study was based on 57 species of teleosts and 35 species of elasmobranchs, that represent only 14% of the diversity described for the area, and the high diversity of some endemic arhynchobatid skates, we estimate that there exist more than 15 species of trypanorhynchs yet to be discovered in coastal waters off Argentina.