Monogeneans in the northernmost neotropical lake: Unexplored species richness and freshwater fish host-parasite associations in Lake Catemaco

This research presents a comprehensive characterization of the species richness of monogenean parasites infecting the ichthyofauna of six freshwater fish families from Lake Catemaco, Mexico, more than twenty-five years after the first documented introduction of exotic monogeneans into native fish populations. Through the analysis of Internal Transcribed Spacer (ITS) sequences, both specialist and generalist monogenean species were identified. Additionally, host-switching events were documented in several species, highlighting ongoing ecological interactions and adaptation processes. The study also led to the identification of previously undescribed monogenean species, contributing to the knowledge of parasite biodiversity in Neotropical freshwater ecosystems.