Parasitos de duas espécies de peixes coletados em três ambientes aquáticos de Alagoas, Brasil e seu uso como bioindicadores de efeito

Abstract

Parasites can be considered environmental quality bioindicators, since their vital functions correlate directly with the environmental factors. The main purpose of this study was to verify the use of parasites from the species Larimus breviceps and Caranx hippos as effect bioindicators for the Mundaú and Manguaba lagoons and sea adjacent. Were necropsied 56 fish in total, 26 of them being L. breviceps, 15 collected from the Mundaú lagoon and 11 from the Manguaba lagoon and 30 C. hippos, 15 of them collected in the Mundaú Lagoon and 15 collected in the nearby marine environment. In the L. breviceps from the Mundaú lagoon were found: 6 taxons of heteroxenic life cycles and 1 monoxenic. In the ones collected from the Manguaba, 4 taxons were of heteroxenic cycle and 1 of monoxenic cycle. The total proportion of heteroxenic and monoxenic parasites (SH/SM) for the L. breviceps parasites collected form the Mundaú Lagoon was of 13, while for the parasites of the same fish species, collected from the Manguaba Lagoon, it was 6. That indicates that the collection sites from the Mundaú Lagoon are less anthropized than the ones from the Manguaba Lagoon. For the species C. hippos of the Mundaú lagoon, were found 9 taxons of parasites with heteroxenic life cycles and 4 of monoxenic cycle. For the marine C. hippos, were also found 9 taxons of parasites with heteroxenic cycles, however, for the parasites with monoxenic life cycle, were found 6 taxons. The proportion SH/SM for the parasites of the Mundaú lagoon C. hippos was of 3,17 and for the marine ones, it was 0,78. That shows a higher pollution level in the Lagoon collection sites than where the larger fish were collected, in the nearby marine environment. Therefore, the parasites from both host fish species analyzed in this work can be used as environmental quality bioindicators. In addition, this study contributes for the knowledge of the parasitic fauna of the fish species studied, also adding a bigger perception of human actions over aquatic organisms.