Metazoários parasitos de plagioscion squamosissimus (HECKEL, 1840) (OSTEICHTHYES: SCIAENIDAE) de lagos de várzea da Amazônia brasileira

Abstract

Brazilian Amazon’s rivers and to present the morphological and molecular characterization of the nematode Anisakis sp. There were collected 75 specimens of P. squamosissimus at the Curuái’s Great Lake, and at the river mouth of the Tapajós river. This study was divided in two parts, thus producing two chapters in this dissertation. The first section describes metazoans which revealed the presence of 16 species of parasites, being them three myxozoans (Myxobolus sp. Ceratomyxa sp. Henneguya sp.), two Trematodes (Austodiplostomum compactum, Digeneans gen. sp. (Metacercariae), two species of monogeneous (Diplectanum sp., Euryhaliotrema sp.), two nematodes (Procamallanus (S) sp. Anisakis sp., Pseudoproleptus sp. (larva), two Acanthocephalas (Rhadinorhynchus plagioscionis e Neoechinorhynchus sp.), one Cestoda and three crustaceans (Therodamas sp. Ergasilus sp. Dolops sp.). The hosts collected in Tapajos river had a lower range of metazoan parasites (H = 0.531) compared to individuals from the Amazon (H = 0.991). The Mann-Whitney test showed no differences between observed Kn and the standard Kn (1.00) (U = 0.14, p = 0.88). Then in the second chapter, the found and identified helminths from the Anisakis genus were used for morphometric characterization, measured and submitted to molecular identification based on the sequencing of 18S and COX1 genes. Anisakis spp., a parasite of P. squamosissimus, was not characterized compatible in the existent literature. The molecular analyzes suggest the existence of a group of cryptic species in the two regions where the fishes were collected.