Integrative taxonomy of Anacanthorus spp. (Monopisthocotyla, Dactylogyridae) parasitizing the gills of Triportheus spp. (Characiformes, Triportheidae) from Brazil.

This study describes seven new species of Anacanthorus (Monopisthocotyla, Dactylogyridae) parasitizing gills of Triportheus spp. (Characiformes, Triportheidae) from two aquatic ecosystems in Brazil. These new species exhibit unique characteristics, such as variations in the morphology of the male copulatory complex and the morphology of the hooks, corroborating a high degree of host-parasite specificity. Despite the broad distribution of Anacanthorus in Characiformes, both molecular and morphological data suggest close coevolution, with parasite lineages often associated with specific host groups. This research expands the known diversity of Anacanthorus within the family Triportheidae, provides the first record of the genus in Triportheus signatus and Triportheus trifurcatus, and emphasizes the need for integrative studies to fully understand the evolutionary patterns of the group. The findings highlight the importance of investigating the parasite fauna in the Salgado River and Tocantins-Araguaia River basin ecosystems, which remain largely understudied, providing a solid foundation for future phylogenetic analyses.