The main objective of the present work was to know the ectoparasitic metazoans that parasitize the "sabalo” B. amazonicus from the natural environment and from culture ponds of the Fernando Alcántara Research Center (CIFAB) of the IIAP, between the months of March to June 2021. It was carried out by means of the observation, search and identification of the ectoparasitic fauna of Brycon amazonicus.The analysis of the fish was carried out in the Laboratory of Parasitology and Aquaculture Health of the IIAP In the present study, 9 species of Monogenoidea (Anacanthorus sp1, sp2, sp3, sp4, A spiralocirrus, A. femoris, A sabalai, A kukamensis and A. rarus), 1 species of Copepoda (Ergasilus bryconis) and 1 species of Branchiura (Argulus multicolor). These data belong to the specimens from the In the natural environment, in the case of specimens from culture ponds, only two species of Monoge...