Diversity of helminth parasites of Colomesus psittacus on the Soure Marine Extractives Reserve in the Brazilian Amazon.

Tropical aquatic ecosystems are among the most vulnerable environments on the planet and have been suffering increasing anthropogenic pressures, generating a marked loss of biodiversity. Especially when the ichthyofauna is approached, there is a loss of biomass consumed by the population, as well as a parasitic fauna that is still little studied, mainly in terms of taxonomic aspects, parasite biology, and the parasite/host relationship. The objective of this study was to record the parasitic fauna of Colomesus psittacus from Marajó Island, State of Pará, in the Brazilian Amazon. The fish were purchased from fishing pens belonging to family units within the Marine Extractive Reserve in the municipality of Soure, where the fish were discarded by fishermen. The fish (n=50) were necropsied, and their organs were individualized in a Petri dish to search for helminths. The helminths were then clarified and identified. Of the 50 specimens examined, 76% were parasitized by one or more species, and a total of 807 parasites were recovered. Among the helminths, it was possible to identify seven nematodes, Huffmanela psittacus (70%), Anisakis sp. (12%), Hysterothylacium sp. (8%), Philometra sp. 1 (28%), Philometra sp. 2 (2%), Cucullanus marajoara (28%), infective larva (L3) of Cucullanus sp. (34%). The trematodes recorded were a trematode Bianium sp. (2%) and type Paramonilicaecum, and two parasites belonging to the phylum Acanthocephala. The helminth community of C. psittacus was characterized by a high richness of nematodes and a small number of digenetics and acanthocephala. This is a new record of parasitic fauna in C. psittacus in Brazil. [ABSTRACT FROM AUTHOR]