A new species of Wallinia Pearse, 1920 (Digenea: Allocreadiidae) collected from Astyanax fasciatus (Cuvier, 1819) and A. lacustris Lucena and Soares, 2016 (Characiformes: Characidae) in Brazil based on morphology and DNA sequences

Abstract

Wallinia brasiliensis n. sp. is described from the intestine of two species of tetras-Astyanax fasciatus (Cuvier, 1819) and Astyanax lacustris Lucena and Soares, 2016-collected from the Batalha River in São Paulo State, Brazil. The new species can be clearly distinguished from the other three congeneric species by its vitelline follicles extending from the genital pore to the end of the caeca, eggs lacking operculum, a larger egg size with a consequently lower number relative to the other three species, and the ovary located opposite the anterior testis. The validity of the new species was confirmed through a phylogenetic analysis of the 28S rRNA gene which showed that the new species is the sister taxon to Wallinia mexicana Pérez-Ponce de León, Razo-Mendivil, Mendoza-Garfía, Rubio-Godoy and Choudhury, 2015, a species infecting Astyanax mexicanus (De Filippi, 1853) in Mexico.

A new species of Creptotrematina (Trematoda: Allocreadiidae) from characid fishes of Brazil: morphological and molecular data

“…aeneus from Mexico and Costa Rica, respectively, was 2% (table 2), which is similar to what has been reported for other species pairs in allocreadiids. Our results show significant genetic divergence for species delimitation of members of Allocreadiidae; these molecular markers have been used for species differentiation in the group (Curran et al ., 2006; Pérez-Ponce de Léon et al ., 2015, 2016; Dias et al ., 2018; Hernández-Mena et al ., 2018). For instance, Hernández-Mena et al .…”

“…Two species of the genus Astyanax Baird & Girard, 1854 were studied herein – Astyanax lacustris and Astyanax fasciatus – and, until this moment, only one species of the allocreadiid genus Wallinia Pearse, 1920 has been recorded parasitizing A . lacustris (Dias et al ., 2018). The genus Creptotrematina Yamaguti, 1954 was erected to include two species of allocreadiids originally described by Freitas (1941) as belonging to the genus Creptotrema Travassos, Artigas & Pereira, 1928 from Brazil and Argentina, as parasites of characid fish: Creptotrematina dissimilis (Freitas, 1941) Yamaguti, 1954 in Tetragonopterus argenteus Cuvier, 1816 in Brazil, and in Astyanax bimaculatus (Linnaeus, 1758) and Astyanax eigenmanniorum (Cope, 1894) in Argentina; and Creptotrematina dispar (Freitas, 1941) Manter, 1962 in Triportheus paranensis (Günther, 1874) in Brazil and Argentina (see Kohn et al ., 2007).…”

A massive Chilodonella hexasticha infestation associated with yellowtail tetra Astyanax lacustris mortality in aquaculture: Identification and pathology

“…Recently, Zago, Franceschini, Müller, and Silva () described a new species of monogenean, Cacatuocotyle papilionis , in the Sapucaí–Mirim River. Vidal, McIntosh, and Luque () described a new species of myxozoa in fish from the Mogi Guaçú River, and Dias et al () described Wallinia brasiliensis in the intestine of yellowtail tetra from the Batalha River. Based on the fact that many fish farmers collect broodstock from the wild and river water is used in fish farms, all these parasites represent a risk to aquaculture at some point and require attention.…”