Caracterização morfológica e filogenia molecular de microparasitos eucarióticos em Batrachoides surinamensis (Bloch e Schneider, 1801) e Menticirrhus americanus (Linnaeus, 1758) capturados no estuário do município de Viseu, estado do Pará

Abstract

The amazonian coastal ecosystems are biologically important, once the abundance of fish in estuaries shows high rates of richness and diversity of ichthyofauna. Native fish are susceptible to acquiring various parasitic infections by various types of microparasites, since their habitat facilitates its propagation and development. Among the resources that have relevance in the fishery production in this environment, we highlight the species Batrachoides surinamensis and Menticirrhus americanus, studied here with the aim of describing the morphological and molecular characteristics of the eukaryotic microparasites (microsporids and myxosporidia) found in these fish from the municipality of Viseu / Pará. Every two months the specimens were collected, necropsied and their organs analyzed in ML. From the parasitized organs fragments and / or cysts were removed, fixed and processed for light microscopy and molecular biology. For phylogenetic studies, the analysis was performed by Bayesian inference and genetic distance (p) methods. Based on the analysis, two phyla of eukaryotic microparasites, Cnidaria and Microsporidia, were diagnosed. The results refer to morphological and phylogenetic studies. For B. surinamensis, a microparasite species of muscular tissue, Kudoa viseuensis n. sp. with parasitic prevalence of 86%; and also, occurrence of the genus Ellipsomyxa in the gallbladder and an unidentified urinary bladder myxosporidium with a prevalence of 56% and 48%, respectively. For M. americanus the presence of xenomas in the gastric mucosa was observed where 20% of the analyzed hosts were parasitized by microsporidium. The infections presented by these mixosporids and microsporids had not yet been described in the literature for these species. More detailed complementary studies are required in transmission and scanning electron microscopy, as well as in molecular biology, to confirm the other parasitic species. In view of the diversity and pathogenicity of these microparasites of the Amazonian ichthyofauna, we affirm the need to intensify the study to contribute to the knowledge of the sanitary status of these fishes in artisanal fishing in northeastern Pará.