The first record of Centrocestus formosanus (Trematoda: Heterophyidae) in southern Brazil supported by molecular data

Abstract

Centrocestus formosanus is a digenean parasite fi rst described from Asia, which parasitizes Melanoides tuberculata (Gastropoda: Thiaridae) at the fi rst intermediate stage, and different fi sh species as second intermediate host. C. formosanus was previously recorded in Brazilian states, but never before in the southern region of this country. Recording and identifi cation of digenean species through morphological identifi cation is a taxonomic challenge. In light of this, we use an integrative taxonomic approach to report the occurrence of cercariae and metacercariae of C. formosanus in molluscs and fi sh, respectively, in an urban park located in southern Brazil. Specimens of M. tuberculata and the fi shes Poecilia reticulata and Xiphophorus sp. (Poeciliidae) were collected for screening for parasites and molecular analyses using partial fragments of the 28S rDNA gene. The identifi cation of C. formosanus obtained from molluscs and fi sh specimens permitted us to partially solve the life cycle of this parasite for the fi rst time in the studied environment, demonstrating the necessity of monitoring and controlling molluscs populations. Nevertheless, our results will support future studies aiming to elucidate the life-cycle of C. formosanus in this region, since all sampled hosts' species are invasive in this environment.