Parasite communities of the gafftopsail pompano Trachinotus rhodopus (Carangiformes: Carangidae): examining the parasite species richness and diversity over time.

In total 949 specimens of Trachinotus rhodopus (Gill) were collected over a 11-year period (from June 2013 to February 2024) from Acapulco Bay, Mexico. Parasite communities in T. rhodopus were quantified and analysed to explore two hypotheses related to their parasite species richness and diversity associated with the bentho-demersal and pelagic habits, and effects of the climatic fluctuations. Thirty-two metazoan parasite taxa/species were identified: three species of 'Monogenea', 14 Digenea, one Aspidogastrea, one Acanthocephala, two Cestoda, three Nematoda and eight Crustacea. The digeneans and copepods were the best represented groups. The component parasite communities were characterised by the numerical dominance of the acanthocephalan Rhadinorhynchus sp. Species richness (15-24 species) was similar to that reported for other species of carangid fish, but the richness of the digeneans was significantly higher. The parasite communities of T. rhodopus exhibited high variability in species composition, suggesting that each species of parasite may respond differently to environmental changes. However, the species richness and diversity were fairly stable over time. Climatic events of La Niña and El Niño probably generated notable changes in the structure of local food webs, thus indirectly influencing the transmission rates of several endoparasite species.