ECOLOGICAL ASPECTS OF METAZOAN PARASITES IN TRACHELYOPTERUS GALEATUS (SILURIFORMES: AUCHENIPTERIDAE) FROM THE PERICUMÃ RIVER, STATE OF MARANHÃO, NORTHEAST BRAZIL

Parasites of the fish Trachelyopterus galeatus from Maranhão

Resumo

The driftwood catfish, Trachelyopterus galeatus, is widely distributed in South American rivers and plays crucial role in the transfer of energy from terrestrial to aquatic ecosystem. Despite this importance, the structure of the parasite community of T. galeatus has not yet been investigated for lowlands of Maranhão State, Brazil. We evaluated 57 specimens of T. galeatus bought from local fisherman at Pericumã river (2°32'22"S, 45°04'27"W), municipality of Pinheiro. Parasitological analysis revealed that 27 hosts were infected with at least one parasite taxon, with a mean of 1.07 ± 1.82 parasites per fish. We found three parasite taxa: a branchiuran, a digenetic and a nematode (larva); all with aggregated distribution. The presence of both adult and larvae indicated that T. galeatus occupies an intermediate trophic level. The community had low diversity and was dominated by the digenean Doradamphistoma parauchenipteri. Fish sex and body length had little influence on the structure of the parasite community.