The Paranapanema River is an important, extensively explored tributary of the Upper Paraná River basin. The fish fauna of the Paranapanema River has been investigated since the 1990s; however, no study has characterized the richness of fish species throughout the basin, including the main channel of the river, marginal lagoons, its tributaries, and sub-tributaries. Thus, we performed a review with 90 independent studies conducted at the upper, middle, and lower sections of the basin. We recorded 225 species, of which 165 were native, and 60 were non-native. We found that 77% of the species within the basin are composed by Siluriformes and Characiformes. Cichliformes had a significant number of non-native species established in impoundment sections of the basin. Incidence-Based Estimators (Bootstrap and Chao 2) demonstrated that the richness of native species is still underestimated. Some native (e.g., Hypostomus ancistroides) and non-native species (e.g., Plagioscion squamosissimus) are widely distributed in the basin, while others had a more restricted distribution. Among the registered species, the family Bryconidae had the highest number of representatives with threatened conservation status. In addition, we observed that the Capivara Reservoir and its tributaries were the most sampled regions, with the majority of studies performed in the Lower Paranapanema basin. The species richness recorded in large tributaries, such as Tibagi, Cinzas, Congonhas, and Pirapó rivers is critical for maintaining the fish fauna in the Paranapanema River. Our contribution may be used to support management actions and conservation strategies, as well as to indicate regions in the basin that need to be better inventoried.

Materials and Methods Study site Fish samples were collected in the region of Serra Azul and Serra do Roncador in the upper-middle Araguaia basin, in the municípios Barra do Garças and Aragarças (Figure 1), in the states of Mato Grosso and Goiás respectively. The climate is tropical wet and characterized by two well defined seasons, rainy season (October to April) and dry season (May to September), with an average temperature of 25.5°C (Pirani et al. 2009). Data collection Ten sites were sampled in the tributaries of the Araguaia basin during the dry season, from July 29 to August 2, 2008 (Table 1). Fish collections were performed using standard ichthyological gear comprising sieves, seine nets and cast nets (IBAMA permit number 12120-1). The sampling effort included 60 minutes of sampling by three people at each site. Fish were fixed in 10% formalin solution and subsequently transferred to 70% ethanol. Species were identified up to the lowest possible taxonomic level, using available literature and further confirmation by experts when possible. The taxonomic classification follows Eschmeyer (2013). Voucher specimens were deposited in the fish collection of the

The southern region of Brazil is characterized by high species diversity and endemism of freshwater fishes distributed across geographically isolated river basins. Microglanis cottoides has a widespread range across these river basins and occurs in sympatry with other endemic species of the genus (e.g. M. cibelae, M. eurystoma, and M. malabarbai). Herein we tested the monophyly of M. cottoides and presented for the first time information about the molecular phylogeny of species in the genus. The results suggest that M. cottoides currently forms a non-monophyletic group which includes populations endemic to the Uruguay River basin that are more closely related to M. malabarbai, and excludes M. cibelae, found to be nested within M. cottoides. Based on an integrative approach using morphological and molecular data, we propose M. cibelae as a junior synonym of M. cottoides, and the populations of the Uruguay River basin previously assigned to M. cottoides in fact belong to M. malabarbai. Our molecular phylogeny shows that M. cottoides is sister to M. parahybae, which is also a coastal species, and M. malabarbai is sister of M. garavelloi, both endemic to inland river basins. The time-calibrated phylogeny indicates that the separation between inland and the coastal clades occurred in the Tertiary period, and that the species within the coastal basins diverged in the Pliocene, which overlaps with the diversification times estimated for the two inland species as well. This pattern of diversification corroborates some previous studies with other fishes from the same region.

Abstract. Garcia DAZ, Vidotto-Magnoni AP, Costa ADA, Casimiro ACR, Jarduli LR, Ferraz JD, De Almeida FS, Orsi ML. 2019. Importance of the Congonhas River for the conservation of the fish fauna of the Upper Paraná basin, Brazil. Biodiversitas 20: 474-481. The Upper Paraná River basin is among the most fragmented watersheds in the world. The Congonhas River belongs to this drainage system, which has its mouth in the Capivara Reservoir and can be considered the largest tributary free-from-dam, becoming important for the maintenance of fish species richness. In order to know more about the species present in this tributary, we aimed to provide an inventory of fish fauna of the Congonhas River and reproductive strategies to determine whether the river is used by migratory species and whether there is a longitudinal variation in the fish assembly. These findings will provide subsidies to contribute to the implementation of policies to protect biodiversity. Samplings occurred in the upper, middle and lower stretches of the Congonhas River during four periods between 1991 and 2011. Fishes were captured using gill nets from 2 to 14 cm mesh sizes between opposite knots and cast nets, identified and categorized according to their reproductive strategies. A total of 4,640 individuals belonging to 63 species, of which 79.4% consisted of Characiformes and Siluriformes were captured. Furthermore, 14% of fish were long-distance migratory species (e.g., Piaractus mesopotamicus, Megaleporinus obtusidens, Prochilodus lineatus, Salminus brasiliensis, Pinirampus pirinampu, and Pseudoplatystoma corruscans). In addition, there was an increase in the fish species richness from upstream to downstream. Management actions such as prohibition of fishing, rehabilitation of riparian vegetation, and protection of the basin against dam construction will reduce anthropogenic impacts on the ecosystem. The Congonhas River highlights the importance of preserving lotic environmental for the conservation of migratory and non-migratory Neotropical fish diversity into a heavily modified watershed.

This study presents a list of species from igarapés tributaries of the rio Acre, Acre State, Brazil. Fish assemblages were sampled in October 2009, August and October 2010, using standard ichthyological gear, along fifteen sampling sites. A total of 11,395 specimens, distributed in 94 species, 24 families and six orders were collected. The most species-rich orders were Characiformes with 45 species (48.4%) and Siluriformes with 33 species (34.7%); from which Serrapinnus gr. microdon (22.4%), Otocinclus vittatus (20.4%), Phenacogaster pectinatus (10.9%), Brachychalcinus copei (5.8%) and Knodus sp. (5.3%) represented 64.8 % of the specimens captured. The species accumulation curve does not present a stabilization tendency, indicating that, additional sampling can increase the number of species. This study has a high importance for the knowledge of the rio Acre fish fauna composition and adds 52 new records of species to the fish fauna of the rio Purus.