Distribution of two monogenean (Gastrocotylidae) from the North Atlantic coast of Morocco

The ecological indexes of infection during that period were calculated as the prevalence, mean intensity, and abundance. For Gastrocotyle trachuri; the prevalence is 51.58%, mean intensity is 4.83, and abundance is 2.49. Whereas Pseudaxine trachuri; we found respectively prevalence is 15.51%, mean intensity is 1.36, and abundance is 0.21. In this study, we also discuss the relation of the fish infection in terms of length and sex.