A new species of Tereancistrum (Monogenea: Dactylogyridae), parasite of Prochilodus lineatus (Characiformes: Prochilodontidae) from southeast Brazil

Abstract

A new species of Tereancistrum Kritsky, Thatcher & Kayton, 1980 collected of Prochilodus lineatus gills from the Batalha River, Tietê-Batalha basin, São Paulo State, Brazil is described. The new species can be distinguished from its congeners mainly by the configuration of the ventral bar, which has an anvil-shaped characteristic with corrugated anterior projection. Tereancistrum takemotoi n. sp. is morphologically similar to T. toksonum Lizama, Takemoto & Pavanelli, 2004 in terms of their dorsal bars (Y-shaped), their dorsal anchors with divergent roots (superficial and deep) wherein their deep root rather elongated, and by the fact that they both have the male copulatory organ counterclockwise. However, only T. takemotoi n. sp. presents the male copulatory organ with 2¼ rings and shows undulations in the anterior margin of the dorsal bar. These undulations are absent in T. toksonum (which only has 1¼ rings). This is the fourth Tereancistrum species described for P. lineatus and the first described for the region from the Tietê-Batalha basin.

Ectoparasitic diversity, gill alterations in Hoplerythrinus unitaeniatus (Characiformes: Erythrinidae) and Cichlasoma bimaculatum (Perciformes: Cichlidae) and quality of fishing water in the Quilombola zone in Maranhão State, Brazil

“…Concerning ectoparasites, different studies carried out in Maranhão State, as well as in other Brazilian states, have shown that the incidence of these organisms in fish is a common issue, whether in fish farms or the natural environment (Cunha 2015, Rodrigues et al 2017, Fujimoto et al 2019, Leite et al 2020. It is worth emphasizing that parasitism in fish is a challenge, regardless of the season of the year, due to the complexity of factors involved in it, such as the ones inherent to hosts (age, immunological status, intercurrent diseases, among others), parasitic agents (species and pathogenicity) or the environment (climate, local hygiene, biosecurity, reservoirs, among others).…”