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Nestedness among species assemblages implies that sites of lower species richness are subsets of richer sites in a regional species pool. This nestedness is a reflection of a non-random process of species loss as a consequence of factors that promote the disaggregation of assemblages. The impoverishment of assemblage diversity is more often observed in fragmented landscapes. This non-random process has important implications for conservation. We recorded 95 species of anurans across 22 protected areas, of which 11 sites were in an urban matrix and 11 were in a non-urban matrix. We found that sites in the urban matrix had lower richness and high values of nestedness with no spatial autocorrelation among geographic distances and species composition. Thus, species were non-randomly distributed across the landscape and a nested pattern was documented from non-urban matrix sites to urban matrix sites. The impoverishment of assemblages toward the urban matrix sites may suggest that protected areas in an urban matrix are less suitable for anuran conservation than those in a non-urban matrix sites. Both the ecological revitalization of protected areas in urban matrix and protection of non-urban forested sites are needed for the conservation of Neotropical anurans.

Understanding the variation of fish assemblages in reservoirs is crucial for precise interpretations of ecological processes. However, representative samples in such environments are subjected both to spatial zonation (longitudinal and transversal gradients) and limitations of fishing gears. We used a large zoned reservoir (Itaipu, Brazil) to perform a quasi-experiment that assessed the relative role of spatial gradients and fishing methods on fish diversity and composition. Active (cast nets, electrofishing and seines) and passive (gillnets and longlines) fishing gears were employed in lotic, transitional and lentic habitats of the reservoir and three large tributaries. In total 6281 individuals of 101 species were captured. Sampling methods and spatial gradients had an influence on species composition, with significant interactions between these factors. In addition, results produced by a variation partitioning analysis suggested that 21 % of the species richness was explained by the sampling methods and 7 % by the longitudinal gradient; whereas for species composition, 12 and 3 % corresponded to sampling methods and transversal gradients, respectively. Overall, our results suggest that variations among fishing gears is greater than across strong spatial gradients, emphasizing the importance of using multiple and complementary fishing methods in reservoirs for characterization of fish assemblages. The interactions between spatial gradients and sampling methods were higher with transversal than with longitudinal gradients, suggesting that substantial differences in species richness and composition among sampling gears depend to some extent on habitat. The approach used here would be applicable to any large zoned inland waterscapeFinancial support was provided by the Spanish Ministry of Economy and Competitiveness (project CGL2013-43822-R), the Government of Catalonia (ref. 2014 SGR 484), and CAPES (Programa Pesquisador Visitante Especial, ref. 88881.068352/2014-01)

A história inicial de vida dos peixes envolve múltiplos processos e estratégias para garantir a sobrevivência e seu estudo fornece importantes informações sobre o estado de conservação das espécies e dos estoques pesqueiros. Neste estudo foi utilizada uma abordagem cienciométrica para investigar o panorama atual da ecologia do ictioplâncton e avaliar a produção científica global, no período de 1990 a 2015, indexada na base Web of Knowledge, com considerações sobre a posição do Brasil no cenário mundial. Os dados investigados foram referentes ao país de origem, aos tipos de ambiente amostrados (marinho ou água doce) e aos tipos de estudos desenvolvidos (experimental, descritivo, modelagem ou preditivo). Também foram investigadas as denominações atribuídas ao ictioplâncton (larva, juvenil, young of the year, etc.) nos títulos e resumos dos artigos. Foram encontrados 1104 artigos publicados por autores de 66 países, cuja maior parte foi classificada como descritiva e relacionada a ambientes marinhos. O Brasil foi o quarto país mais produtivo, depois dos EUA, Austrália e Canadá. A Suíça se destacou pela publicação de estudos experimentais e a Noruega por desenvolver estudos de modelagem. Os estudos preditivos advieram, principalmente, do Canadá, Austrália e Alemanha. Os temas mais frequentes, em nível global, foram "distribuição" e "estrutura das assembleias", seguidos de alguns classicamente voltados para ecologia e monitoramento dos recursos pesqueiros, como "locais de desova" e "recrutamento". Outros tópicos de ecologia, como "competição", "predação", "impactos antropogênicos" e "invasões biológicas" ficaram entre os menos estudados. Os resultados permitem sugerir desafios para o futuro dessa ciência no mundo: desenvolver trabalhos ecologicamente mais abrangentes, de maneira a testar hipóteses e responder a perguntas que vislumbram problemáticas atuais, amplamente discutidas em outras áreas, e.g. as influências de mudanças globais, ainda pouco abordadas por ictioplanctólogos. No Brasil, as pesquisas poderiam visar o conhecimento acerca dos milhares de espécies de peixes, sobre os quais pouco se sabe a respeito dos requerimentos ambientais durante as fases iniciais de vida, porém sem perder o foco nas questões ecológicas de interesse global. Palavras-chave: coortes jovens; fase larval ; história inicial de vida; ovos e larvas; zooplankton. ABSTRACT-ECOLOGY OF ICHTHYOPLANKTON: A SCIENTOMETRIC APPROACH The early life history of fish involves multiple processes and strategies to ensure the survival, and the knowledge on this field provides important information about the conservation of species and fish stocks. We used a scientometric approach to investigate the current situation of ichthyoplankton ecology and to assess the overall scientific production indexed in the Web of Knowledge databank from 1990 to 2015. We additionally analyzed Brazil's position on the world ranking. The information collected covered the country where the study was developed, the different sampled environments (marine or freshwater), and the ...

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Fish populations that reside in completely isolated freshwater ecosystems are rare worldwide. The Vila Velha State Park (VVSP), located in southern Brazil, is recognized for its arenitic formations called sinkholes (furnas), which are completely isolated. Fish populations within, such as those of Psalidodon aff. fasciatus, often develop vertebral malformations due to this isolation from other conspecifics and other species. In this study, we analyzed geometric morphology in digital radiographs to identify congenital deformations of Psalidodon aff. fasciatus in Furna 2 of VVSP. We found many fish with spinal deformities, including wide variation in the number of caudal vertebrae and corporal deformations related to a flattened body and spinal curvature. Females were more affected than males. We also demonstrated that these deformations reflect inbreeding and an absence of gene flow in the population. In conclusion, isolated populations such as fish species in furnas are potential models for evo-devo research.

The Neotropical region hosts 4225 freshwater fish species, ranking first among the world's most diverse regions for freshwater fishes. Our NEOTROPICAL FRESHWATER FISHES data set is the first to produce a large‐scale Neotropical freshwater fish inventory, covering the entire Neotropical region from Mexico and the Caribbean in the north to the southern limits in Argentina, Paraguay, Chile, and Uruguay. We compiled 185,787 distribution records, with unique georeferenced coordinates, for the 4225 species, represented by occurrence and abundance data. The number of species for the most numerous orders are as follows: Characiformes (1289), Siluriformes (1384), Cichliformes (354), Cyprinodontiformes (245), and Gymnotiformes (135). The most recorded species was the characid Astyanax fasciatus (4696 records). We registered 116,802 distribution records for native species, compared to 1802 distribution records for nonnative species. The main aim of the NEOTROPICAL FRESHWATER FISHES data set was to make these occurrence and abundance data accessible for international researchers to develop ecological and macroecological studies, from local to regional scales, with focal fish species, families, or orders. We anticipate that the NEOTROPICAL FRESHWATER FISHES data set will be valuable for studies on a wide range of ecological processes, such as trophic cascades, fishery pressure, the effects of habitat loss and fragmentation, and the impacts of species invasion and climate change. There are no copyright restrictions on the data, and please cite this data paper when using the data in publications.