Lepeophtheirus azoricus n. sp (Copepoda: Caligidae) parasitic on dusky grouper, Epinephelus marginatus, from Atlantic waters off the Azores, Portugal

Abstract

A new species of caligid copepod, Lepeophtheirus azoricus n. sp., is described from the dusky grouper, Epinephelus marginatus (Lowe), caught in Atlantic waters off Faial Island in the Azores. Both sexes of the parasite were collected from the body surface of the host by the application of osmotic shock. The new species can be distinguished from its congeners by the following set of characters: (1) an obvious conical projection on the posterolateral corners of the genital complex, (2) the relative lengths of the second and third spines on the terminal exopodal segment of leg 4, (3) the relative lengths of the setal elements on legs 5 and 6 of the male, (4) the ornamentation, and lack of a myxal process, on the proximal segment of the maxilliped in both sexes, (5) the unusual structure of the male antenna.