The ecology, distribution, and taxonomy of bopyrid isopod species are often omitted from studies not systematically addressed to crustaceans. From a wider study of zooplankton in coastal and reef waters of the Mexican Caribbean Sea, two bopyrid species were collected, Probopyrinella latreuticola, attached to the branchial chamber of Latreutes fucorum and Probopyrus pandalicola parasitizing the branchial chamber of Palaemon northropi. For both parasite-host associations, these records represent a new locality and the southernmost record in the Mexican Caribbean. A map and a list of the bopyrid species belonging to Bopyridae recorded in the Mexican Caribbean are provided.