Fish of the Callychthyidae family are of great commercial importance in the Peruvian Amazon, since their species are exported to different countries around the world. These fish, kept in captivity, can present infestations caused by monogenoids in skin and/or gills. Given the need to know the monogenoids that parasitize commercially important callitrichids, the main objective of this study was the taxonomic identification at species level of the monogenoids present in the skin and gills of callitrichids (Siluriformes: Callychthyidae). The study was conducted from January to June 2023, through the observation, search and identification of ectoparasites in thirteen species of Callitrichids (20 individuals per fish) corresponding to: Brochis splendens, B. multiradiatus, B. virginiae, B. ambiacus, B. agassizii B. reticulatus, B. arcuatus, B. leopardus, Hoplisoma panda, H. trilineatus, H. wei...