Abstract:We compiled data on fish fauna of the Ivaí River basin from recent specialised literature, standardised sampling and records of species deposited in fish collections. There were 118 fish species of eight orders and 29 families. Of these, 100 species are autochthonous (84.8%), 13, allochthonous (11.0%) and five, exotic (4.2%). The main causes for the occurrence of non-native species are escapes from aquaculture, introduction for fishing purposes and the construction of the Itaipu hydroelectric plant. The predominance of small and medium-sized Characiformes and Siluriformes, including 13 species new to science, accounts for approximately 11.0% of all species and 13.0% of all native species. About 10.2% of all species and 12.0% of all native species are endemic to the upper stretch of the Ivaí River, isolated by numerous waterfalls in tributary rivers and streams. The Ivaí River basin is subjected to various anthropogenic interferences such as pollution, eutrophication, siltation, construction of dams, flood control, fisheries, species introduction and release of fingerlings. These activities raise concerns about biodiversity of Brazilian inland waters especially regarding the fish fauna; the basin of the Ivaí River already has species classified in categories of extinction risk: Brycon nattereri and Apareiodon vladii (Vulnerable) and Characidium heirmostigmata and Steindachneridion scriptum (Endangered). The high species richness of native fish, endemism of some, high environmental heterogeneity, high risk of extinction and lack of knowledge of several other species along with the eminent human activities raise the need to enrich the scientific knowledge for future conservation efforts for the studied basin. Resumo: Nós compilamos dados sobre a diversidade da ictiofauna da bacia do rio Ivaí proveniente de recentes informações contidas em estudos divulgados na literatura especializada, coletas padronizadas e registros das espécies depositadas em coleções ictiológicas. Foram registradas 118 espécies de peixes pertencentes a oito ordens e 29 famílias. Dessas, 100 são autóctones, (84.8%), 13 são alóctones (11.0%) e cinco são exóticas (4.2%). As principais causas da ocorrência de espécies não nativas são escapes da piscicultura, introduções para pesca e a construção da usina hidrelétrica de Itaipu. Ocorre o predomínio de espécies de Characiformes e Siluriformes com porte pequeno e médio, sendo que 13 espécies são novas, o que representa aproximadamente 11.0% do total de espécies e 13.0% do total de espécies nativas. Ainda, aproximadamente 10.2% do total de espécies e 12.0% do total de espécies nativas correspondem a espécies endêmicas, isoladas pela presença de inúmeras cachoeiras em rios e riachos afluentes no trecho superior do rio Ivaí. A bacia do rio Ivaí está sujeita a uma variedade de interferências antrópicas como poluição, eutrofização, assoreamento, construção de represas, controle do regime de cheias, pesca, introduções de espécies e soltura de alevinos. Tais atividades apontam alarmantes preocupaçõe...

Knowledge of the fish species in river basins is among the minimum requirements for the management of water and fish resources. Therefore, the aim of this study was to update the fish species composition of the Piquiri River basin, upper Paraná River basin. Data were gathered from recent information published in specialized literature and records for ichthyology collections. This update reports the occurrence of 152 fish species distributed in 8 orders, 31 families, and 89 genera. Non-native species accounted for 20% of all species, and the construction of the Itaipu Power Plant and its fish ladder were the main vectors of introduction. Three percent of the species were endangered, and 11% were classified as migratory. The Piquiri River basin harbors a large number of species, some of which are rare, endangered, migratory, endemic, and even unknown by science. Because of this, maintaining the integrity of this river basin will support the persistence of regional biodiversity. Keywords: Ichthyofaunal survey, species knowledge, preservation, upper Paraná River basin.Atualização da ictiofauna da bacia do rio Piquiri, Paraná, Brasil: uma área prioritária para conservaçãoResumo: O conhecimento das espécies de peixes existentes em uma bacia hidrográfica é condição mínima necessária para a implantação de qualquer medida de manejo dos recursos hídricos e pesqueiros. Dessa forma, o objetivo deste estudo foi realizar uma atualização da composição das espécies de peixes da bacia do rio Piquiri, sistema do alto rio Paraná, proveniente de recentes informações contidas em estudos divulgados na literatura especializada e registros de espécies depositadas em coleções ictiológicas. A atualização do levantamento ictiofaunístico da bacia do rio Piquiri revelou a ocorrência de 152 espécies, as quais foram distribuídas em oito ordens, 31 famílias e 89 gêneros. Vinte por cento das espécies foram consideradas não nativas. O principal vetor de introdução foi a construção da barragem de Itaipu e seu sistema de transposição. Três por cento das espécies apresentaram alguma ameaça de extinção e 11% foram classificadas como migradoras. A bacia do rio Piquiri comporta grande número de espécies, algumas delas raras, ameaçadas de extinção, migradoras, endêmicas e até mesmo desconhecidas pela ciência. Dessa forma, a manutenção da integridade da bacia promoverá a persistência da biodiversidade regional. Palavras-chave:Levantamento ictiofaunístico, conhecimento das espécies, preservação, bacia do alto rio Paraná.

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.

The rio Ribeira de Iguape basin (Paraná State) is highly relevant for the preservation of remnants of the Atlantic Forest. Its high levels of diversity and fish endemism explain the river dynamics promoted by the Ponta Grossa Arch, a geological structure that promotes headwater capture and isolation between the upper rio Paraná drainage, the rio Iguaçu and the rio Ribeira de Iguape. Here, our objective was to provide an unprecedented inventory for headwater streams of the rio Ribeira de Iguape basin at the boundaries of the Ponta Grossa Arch. We found 29 species of fish representing four orders and nine families. Siluriformes was the richest order followed by Characiformes. Nine species presented high abundance of sampled individuals, contributing with 87.8% of the collections. Four species appeared in less than 25% of the sampled sites (occasional), and six species appeared in more than 50% (constant). We identified three non-described species and one non-native (Coptodon rendalli). Two species had their geographical distribution extended and the presence of Astyanax bifasciatus, endemic to the Iguaçu river basin, ratifies recent events of headwater capture between coastal drainages and those that flow into the continent. Studies of biogeographic divisors are necessary to explain the origin and dispersion processes of species in order to direct studies on diversity and preventive management actions. Coptodon rendalli (Tilapia) is an alarming record on the introduction of species in the region.

The current analysis investigates whether the uplift of the Serra da Esperança and the Ponta Grossa Arch in the Serra Geral resulted in ichthyofaunistic changes in adjacent basins. For this, we describe the phylogeographic structure among populations of Trichomycterus collected in hydrographic basins in southern Brazil by using partial nucleotide sequences of the mitochondrial gene Cytochrome C Oxidase subunit I. Analyses revealed that the nomenclature Trichomycterus davisi fails to contain the whole genetic diversity range found in the collected specimens and indicates at least six genetic lineages in Trichomycterus. Diagnostic morphological characteristics not associated to T. davisi could be identified in some specimens from the Iguaçu Piquiri haplogroup, indicating the occurrence of species Trichomycterus stawiarski. The lack of morphological differences among the other clades clearly suggests a cryptic species case. Molecular analyses revealed at least five new species besides T. davisi in the hydrographic basins and support the interpretation that genetic structure in T. davisi species complex is explained by tectonic events intrinsic to the areas of influence of Serra da Esperança and the Ponta Grossa Arch which occurred around 1.7 My.

In this study we describe areas of endemism from Brazilian mountaintops associated with campo rupestre vegetation based on taxonomically verified records of Microlicieae (Melastomataceae). To test the relevance of taxonomically vetted data, we compared these areas with those recovered using records downloaded from the Global Biodiversity Information Facility (GBIF) website. A total of 12 areas of endemism are recognized and described, of which only eight (66%) were retrieved using GBIF data. With 1º and 0.5º cells, analyses of GBIF data didn’t detect both individual and consensus areas of endemism with Endemicity scores as high as analyses of taxonomically verified data. Records based on misidentified specimens and/or incorrect coordinates affected the detection of areas of endemism using GBIF data. Our results show that taxonomically verified data may improve the efficiency of areas of endemism identification. Besides, the results suggest that the recovery of stable and continuous areas of endemism may be improved by using larger cells and adopting the loose criterion rule to merge individual areas of endemism into consensus areas. Biogeographically, the results indicate that the evolutionary histories of Chapada Diamantina, Southern Espinhaço and Brazilian Central Plateau were related to the radiation of Microlicieae, especially the genera Lavoisiera, Microlicia, and Trembleya. The expansion of areas of endemism in the Cadeia do Espinhaço was probably accelerated by climatic instability and glaciation cycles from Pliocene to Pleistocene.

The process of urbanisation is increasing the frequency and magnitude of fluctuations in the availability of food resources for fish. In this study, we investigated whether the diet and prey selected by the guppy Poecilia reticulata reflect the different levels of urbanisation using the total area of impervious surface soil as the metric. Rural streams (low percentage of urbanisation—LPU) and urban streams (high percentage of urbanisation—HPU) were sampled during both the rainy and dry seasons. The hypothesis tested was that the diet and selective behaviour differ spatially and seasonally between LPU and HPU streams. Among the analysed items, seasonal significant differences were only observed in HPU streams. In LPU streams, the trophic spectrum was wider, and a higher diversity of prey was selected. In HPU streams, the diet richness was lower with a dominance of Chironomidae, and there was also less variability in selected prey. Ephemeroptera and Trichoptera were always avoided, but Coleoptera were avoided only in LPU, while Oligochaeta were avoided in HPU streams. Thus, the diet and prey selected by P. reticulata were different between LPU and HPU streams, and this species has potential to compete for food with the native fauna in a wide variety of environmental conditions and available resources. Therefore, this dietary flexibility probably offers competitive advantages when colonising and establishing in a new habitat.

Landscape dynamics are widely thought to govern the tempo and mode of continental radiations, yet the effects of river network rearrangements on dispersal and lineage diversification remain poorly understood. We integrated an unprecedented occurrence dataset of 4,967 species with a newly compiled, time-calibrated phylogeny of South American freshwater fishes—the most species-rich continental vertebrate fauna on Earth—to track the evolutionary processes associated with hydrogeographic events over 100 Ma. Net lineage diversification was heterogeneous through time, across space, and among clades. Five abrupt shifts in net diversification rates occurred during the Paleogene and Miocene (between 30 and 7 Ma) in association with major landscape evolution events. Net diversification accelerated from the Miocene to the Recent (c. 20 to 0 Ma), with Western Amazonia having the highest rates of in situ diversification, which led to it being an important source of species dispersing to other regions. All regional biotic interchanges were associated with documented hydrogeographic events and the formation of biogeographic corridors, including the Early Miocene (c. 23 to 16 Ma) uplift of the Serra do Mar and Serra da Mantiqueira and the Late Miocene (c. 10 Ma) uplift of the Northern Andes and associated formation of the modern transcontinental Amazon River. The combination of high diversification rates and extensive biotic interchange associated with Western Amazonia yielded its extraordinary contemporary richness and phylogenetic endemism. Our results support the hypothesis that landscape dynamics, which shaped the history of drainage basin connections, strongly affected the assembly and diversification of basin-wide fish faunas.