Parasitic monogenoideans of Sciades herzbergii as bioindicators of environmental quality in amazonian estuarines ecosystems

Abstract This study evaluated the use of gill parasitic monogenoideans from Sciades herzbergii (Siluriformes: Ariidae) as bioindicators environmental quality in Amazonian estuarine ecosystems. Fish were caught tidal channels an impacted area - IA, near port São Luís and a reference RA, Caeté estuary, Bragança. The influence capture site seasonality on parasite abundance, variables biometric data hosts verified. A total 416 S. specimens analyzed. weight length fish RA greater than those IA. relative condition factor was influenced by seasonality. 4,265 monogenoidean following species identified: Chauhanellus boegeri, C. susamlimae, velum, Calceostomella Dactylogyridae gen. sp. seasonal mean abundance susamlimae significantly different, with highest values recorded during dry season. site. During rainy period, indices higher is bioindicator sensitive to low water quality, especially relation turbidity Amazon estuaries.