Abstract

Eleginops maclovinus, a potential species for the diversification of the aquaculture in Chile, has been reported as a natural host of Caligus rogercresseyi, a parasite that severely affects salmon grown in sea cages in southern Chile, and also as an important host for Lepeophtheirus mugiloidis. In order to contribute to the biological knowledge of L. mugiloidis, adult lice were collected from infested E. maclovinus in the field to compare with the life cycle of C. rogercresseyi. The study showed that the life cycle of L. mugiloidis was similar to the life cycle recently reported for L. salmonis, comprising eight stages of development, with only two chalimus stages, differing from C. rogercresseyi which has four chalimus stages and does not present preadult stages. L. mugiloidis reached the adult stage at 467oD, while C. rogercresseyi reached the adult stage at 382oD. The average size of females of L. mugiloidis was 44% larger than males, different from C. rogercresseyi, where females were 13.4% larger than males in samples collected from the field and 9.9% in samples produced under laboratory conditions.