First report of Dendrorchis retrobiloba Volonterio & Ponce de León, 2005 (Digenea, Gorgoderidae) in Astyanax aff. fasciatus (Cuvier, 1819) (Characiformes, Characidae) from southern Brazil

Abstract

Dendrorchis retrobiloba Volonterio & Ponce de León, 2005 was first described from the swim bladder of Astyanax fasciatus (Cuvier, 1819) from Montevideo, Uruguay. In this study, we necropsied specimens of A. aff. fasciatus collected from Lake Guaíba, in Rio Grande do Sul, Brazil, for the analysis of their helminths. The digeneans were identified as D. retrobiloba by their elongated body, oral sucker longer than ventral sucker, and 2 posterior lobes. This is the first report of D. retrobiloba in A. aff. fasciatus from Lake Guaíba and extends the known geographic distribution of this parasite.

Revalidation of Saccocoelioides bacilliformis (Digenea, Haploporidae) parasitizing species of Astyanax (Characiformes, Characidae) from southern Brazil

“…(70° GL ethanol -93 parts; formalin 37% -five parts; glacial acetic acid -two parts) for 48 hours and then stored in 70° GL ethanol (Amato & Amato, 2010). Helminths were stained with Delafield's hematoxylin, clarified in cedarwood oil and mounted using Canada balsam (Amato & Amato, 2010;Gallas & Utz, 2019).…”

“…Their helminth fauna is still very poorly known and considering the trematodes, only three species of digenetic trematodes (Dendrorchis retrobiloba Volonterio & Ponce de Léon, 2005, Genarchella parva Travassos, Artigas & Pereira, 1928and Zonocotyle bicaecata Travassos, 1948 have been reported in A. aff. fasciatus (Fortes & Hoffmann, 1995;Gallas & Utz, 2019). After the examination of the specimens of Saccocoelioides found in different species of Astyanax, we propose the revalidation of S. bacilliformis due the shape of body, position of caecal bifurcation, uterus and vitellarium.…”