Helminth fauna of Astyanax fasciatus Cuvier, 1819, in two distinct sites of the Taquari River, São Paulo State, Brazil

Abstract

This study assessed the helminth fauna of Astyanax fasciatus in two distinct sites of the Taquari River, São Paulo State, with 30 individuals sampled in a lotic site and 30 in a lentic site, recording the monogeneans: Cacatuocotyle paranaensis, Characithecium costaricensis, Diaphorocleidus kabatai, Jainus sp., Notozothecium sp. and Gyrodactylus sp., the digenean Antorchis lintoni and no-identified metacercariae; the nematode Procamallanus (Spirocamallanus) inopinatus and noidentified larvae. The mean abundances of total monogeneans (U = 1053; p = 0.042) and C. costaricensis (U = 1107; p = 0.005) were higher in the lotic site. This difference may be due to the higher density of the host population in the lotic site, and the water transparence in lentic environments that prevents A. fasciatus to form shoals, precluding the exchange of parasites with direct cycle within a host population. This study is the first report of the helminth fauna of A. fasciatus in the Taquari River, with ten taxa recorded, and reports A. fasciatus as a new host for Notozothecium sp. and C. paranaensis.

Aggregation and negative interactions in low-diversity and unsaturated monogenean (Platyhelminthes) communities in Astyanax aeneus (Teleostei) populations in a neotropical river of Mexico

“…Some studies focused on the spatial variation of parasites of riverine fish have shown that the composition of parasite communities is relatively persistent (Knipes and Janovy, 2009; Ferrari-Hoeinghaus et al, 2006; Ferreira-Sobrinho and Tavares-Dias, 2016). By contrast, other studies report considerable changes in the community structure across such a spatial gradient (Weichman and Janovy, 2000; Bellay et al, 2012; Acosta et al, 2015; Córdova and Pariselle, 2007; Espinal-Carrión and López-López, 2010). Hence, doubts remain as to what extent fish parasite communities in a river are independent between host populations that inhabit that river.…”

A new species of Characithecium (Monogenea: Dactylogyridae) from external surface and gills of two species of Astyanax (Ostariophysi: Characidae) in southern Brazil

“…Data on ecological parameters of infestations are only available from Mendoza-Franco et al (2003), Rossin and Timi (2014) and Acosta et al (2015). The low sample size (n = 2 and n = 1) of C. costaricensis parasitizing A. fasciatus collected in 2 rivers in Nicaragua by Mendoza-Franco et al (2003) prevents the comparison with the findings of the current study.…”

“…Characithecium costaricensis has been recorded in the following hosts and locations: A. fasciatus in Mexico (Mendoza-Franco, Scholz, Vivas-Rodríguez, & Vargas-Vázquez, 1999), Nicaragua (Mendoza-Franco, Posel, & Dumailo, 2003, Costa Rica (Kritsky & Leiby, 1972;Price & Bussing, 1967), Panama (Mendoza-Franco et al, 2009), and Colombia (Kritsky & Thatcher, 1974); Astyanax aeneus (Günther, 1860) in Mexico (Mendoza-Franco et al, 2009); Astyanax ruberrimus Eigenmann, 1913in Panama (Mendoza-Franco et al, 2009; A. bimaculatus and Curimata argentea (= Steindachnerina argentea (Gill, 1858)) in Trinidad and Tobago (Molnar, Hanek, & Fernando, 1974). In Brazil, C. costaricensis was recorded in A. fasciatus (Acosta, Queiroz, Brandão, & Silva, 2015;Gioia et al, 1988), A. scabripinnis (Gioia et al, 1988), and A. altiparanae (Azevedo et al, 2007). The other congeners (C. chascomusensis, C. longianchoratum, C. robustum, C. quadratum, and C. chelatum) were recorded in Oligosarcus jenynsii (Günther, 1864) in Argentina (Rossin & Timi, 2014).…”

“…from a subsample (n = 10) of the 54 collected O. jenynsii. Acosta et al (2015) reported the ecological parameters of C. costaricensis in A. fasciatus collected in 2 environments. In a lotic ecosystem (n = 30) prevalence was 83.3%, the average intensity of infestation, 2.3, and the average abundance, 1.9, whereas these figures were 66.7%, 1.3, and 0.9, respectively, in a lentic ecosystem (n = 30).…”

“…in A. fasciatus and A. jacuhiensis reported in the present study. Habitat characteristics and host population density are potential causes of such differences (Acosta et al, 2015;Paraguassú & Luque, 2007).…”