[Transversal partitioning and interspecific associations in communities of ectoparasitic metazoans in marine sciaenid fishes from Peru].

During 1987 and 1988 marine sciaenid fishes from the central Peruvian coast were examined: 237 Menticirrhus ophicephalus, 124 Paralonchurus peruanus, 249 Sciaena deliciosa, 50 Sciaena fasciata and 311 Stellifer minor. Thirty metazoan ectoparasites were identified, 18 helminths and 12 crustaceans. Paralonchurus peruanus was the species with higher number of ectoparasite species (11). The communities of ectoparasites were dominated by diplectanid monogeneans. The following showed preference by some site of infestation in their transversal partitioning: Rhamnocercoides menticirrhi, Rhamnocercus spp., Diplectanum sp., Pseudohaliotrema paralonchuri, Pedocotyle annakohni, P. bravoi, Caligus callaoensis and Lernanthropus huamani. With the exception of P. peruanus, these fishes showed an overall positive association in their ectoparasite communities. Menticirrhus ophicephalus and S. deliciosa had the most pairs of associated and covariated species. Paralonchurus peruanus and S. minor showed no interspecific associations. Negative interspecific association and covariation were not determined. The pair R. menticirrhi-L. huamani (in M. ophicephalus) had the highest association degree. These results suggest an absence of competitive interspecific processes.