Inventory of the ichthyofauna from the Jordão and Areia river basins (Iguaçu drainage, Brazil) reveals greater sharing of species than thought

Abstract

Recent sampling on fish from the headwaters of the Jordão and Areia rivers, combined with collection databases and specialized literature reports, yielded the first species inventory. Both basins reflect the high endemism rate associated with the Iguaçu River. However, four species previously thought to be restricted to the Jordão River basin are now known to also occur in the basin of the Areia River: Astyanax jordanensis Vera Alcaraz, Pavanelli & Bertaco, 2009; Characidiumtravassosi Melo, Buckup & Oyakawa, 2016; Jenynsia diphyes Lucinda, Ghedotti & Graça, 2006; and Trichomycterus igobi Wosiacki & de Pinna, 2008. This suggests an ancestral connection between the tributaries of the Jordão and Areia rivers, with putative drainage rearrangements resulting from the uplift of the Serra da Esperança. The endemic fauna of this region is presently threatened by invasive species, the construction of dams, and other human activities.

Fish fauna in forested and rural streams from an ecoregion of high endemism, lower Iguaçu River basin, Brazil

“…However, similar to found herein, Trichomycteridae have been representative in low Iguaçu streams (Frota et al 2016b, Larentis et al 2016, probably by morphological adaptations of its species to dwelling in varied streams (Casatti 2003). Although, Trichomycterus sp.…”

“…According to Albert & Reis (2011) the predominance of Siluriformes and Characiformes in neotropical ichthyofauna could be related to Gondwana vicariant processes, isolating in South and Central America few high phylogenetic clades, but that evolved and diversified broadly at the region. Like in the present study, where 80.8% of species were Siluriformes or Characiformes and the others orders compassing only one or two species, the predominance of Siluriformes and Characiformes seems to be still more exacerbate in smaller water bodies (Frota et al 2016b, Larentis et al 2016, when compared to downstream courses and reservoirs.…”

“…On the other hand, these results represent a quasi-perfect species subset, corresponding to 24.5% of the 106 species mentioned in Baumgartner et al (2012). Frota et al (2016b) registered similar low fish richness (n=27) and higher fish composition similarities (above 45%), with the principal channel to streams of the two larger tributaries of the right bank (Jordão and Areia) of low Iguaçu River basin. This high similarity between local and broader spatial distributions could be explained by: i) lacking larger migratory species in Iguaçu River basin that are deeper channel dwellers in the Paraná River and others tributaries (Agostinho et al 2003(Agostinho et al , 2008; ii) the wide ability of the characins of genus Astyanax to colonize practically all environments of basin, including large and small inland water or even reservoirs.…”

“…In addition, the studies of Iguaçu ichthyofauna have been smaller when compared to the upper Paraná basin (Langeani et al 2007, Cetra et al 2016, not encompassing large check lists of this region. Besides, there is yet the need of a compilation with an accurate systematic review to stream fish fauna of local regions, because some apparently species with restricted occurrence, showed broader distribution in more detailed studies (Frota et al 2016b).…”

Update on the ichthyofauna of the Piquiri River basin, Paraná, Brazil: a conservation priority area

“…The former species is reported as endemic to the Iguaçu River basin , while the latter is regarded as endemic to the upper Ivaí River basin (Frota et al 2016a). Therefore, the presence of these species in the Piquiri River basin suggests past connections between the upper courses of those basins that might have occurred prior to the uplift of Serra da Esperança, which caused the isolation of the respective headwaters (Frota et al 2016b). Thus, the identification of an endemic zone in the neighboring region between the Piquiri, Ivaí, and Jordão basins would allow an improved understanding of the local biota evolution (Morrone 1994) in addition to a prioritization of its value for biodiversity conservation purposes (Löwenberg-Neto & Carvalho 2004).…”