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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.

Made available in DSpace on 2022-04-28T19:42:34Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-10-01 The Tocantins-Araguaia Basin is one of the largest river systems in South America, located entirely within Brazilian territory. In the last decades, capital-concentrating activities such as agribusiness, mining, and hydropower promoted extensive changes in land cover, hydrology, and environmental conditions. These changes are jeopardizing the basin’s biodiversity and ecosystem services. Threats are escalating as poor environmental policies continue to be formulated, such as environmentally unsustainable hydropower plants, large-scale agriculture for commodity production, and aquaculture with non-native fish. If the current model persists, it will deepen the environmental crisis in the basin, compromising broad conservation goals and social development in the long term. Better policies will require thought and planning to minimize growing threats and ensure the basin’s sustainability for future generations. Núcleo de Estudos Ambientais Universidade Federal do Tocantins (UFT) Programa de Pós Graduação em Ecologia de Ambientes Aquaticos Continentais (PEA) Universidade Estadual de Maringá (UEM) Museu Paraense Emílio Goeldi Grupo de Estudos em Leishmanioses Instituto René Rachou Fundação Oswaldo Cruz (FIOCRUZ) Universidade Estadual Paulista “Júlio de Mesquita Filho” Museu de Zoologia e Taxidermia José Hidasi Universidade Estadual do Tocantins (Unitins) Departamento de Ecologia Universidade Federal de Goiás (UFG) Laboratório de Ictiologia Departamento de Biologia Universidade Federal de Sergipe (UFS) Laboratório de Paleontologia e Evolução Curso de Geologia Universidade Federal de Goiás (UFG) Departamento de Ecologia Universidade Federal do Rio de Janeiro (UFRJ) Universidade Federal de Goiás (UFG) Laboratório de Biogeografia e Ecologia Aquática Universidade Estadual de Goiás Department of Fish and Wildlife Conservation Virginia Polytechnic Institute and State University Herbário do Tocantins Núcleo de Estudos Ambientais Universidade Federal do Tocantins (UFT) Laboratório de Ictiologia Sistemática Núcleo de Estudos Ambientais Universidade Federal do Tocantins (UFT) Departamento de Zoologia Universidade de Brasília Researcher Departamento de Ecologia Universidade de Brasília (UnB) Instituto Nacional de Pesquisas da Amazônia (INPA) Laboratório de Ecologia de Peixes e Invasões Biológicas Universidade Estadual de Londrina (UEL) Laboratório de Entomologia Universidade Federal do Tocantins (UFT) Universidade Federal de Pelotas (UFPel) Environmental Sciences Program-CIAMB Universidade Federal de Goiás (UFG) Universidade Federal de Mato Grosso (UFMT) Campus Universitário do Araguaia Laboratório de Microbiologia Universidade Federal do Tocantins (UFT) Fundação Brasileira para o Desenvolvimento Sustentável (FBDS) & Universidade Federal de Goiás (UFG) Laboratório de Ecologia e Zoologia (LABECZ) Universidade Federal do Tocantins (UFT) Laboratório de Ecologia de Peixes Departamento de Ecologia Universidade do Estado do Rio de Janeiro (UERJ) Laboratório de Análise e Síntese em Biodiversidade Departamento de Botânica Universidade Federal do Paraná (UFPR) Secretaria de Estado da Educação de Goiás-(Seduc-GO) UNISANTA PPGECOMAR Universidade Federal do Tocantins (UFT) Laboratório de Paleobiologia Universidade Federal do Tocantins (UFT) Departamento de Ecologia e Conservação Universidade Federal de Lavras (UFLA) Laboratório de Caracterização de Impactos Ambientais (LCIA) Universidade Federal do Tocantins (UFT) Embrapa Cerrado Instituto de Biodiversidade e Sustentabilidade Universidade Federal do Rio de Janeiro Programa de Pós-Graduação em Ecologia Universidade Federal do Pará (UFPA) Laboratório de Análises Geoambientais (LGA) Universidade Federal do Tocantins (UFT) Centro de Biologia Aquática Pontifícia Universidade Católica de Goiás Laboratório de Biodiversidade Universidade Evangélica de Goiás Escola de Ciências Agrárias e Biológicas Pontifícia Universidade Católica (PUC) Laboratório de Genética & Biodiversidade - ICB/UFG Núcleo de Pesquisas em Limnologia Ictiologia e Aquicultura (Nupelia) Universidade Estadual de Maringá (UEM) Departamento de Direito Universidade Federal do Tocantins (UFT) Núcleo de Estudos e Pesquisas Ambientais e Limnológicas (Nepal) Universidade de Brasília (UnB) Laboratório de Ecologia e Conservação (LEC) Universidade Federal do Paraná (UFPR) Coordenação de Biodiversidade Instituto Nacional de Pesquisas da Amazônia (INPA) Universidade Estadual Paulista “Júlio de Mesquita Filho”

Estudos sobre producao sao fundamentais para o entendimento de varios aspectos da organizacao e funcionamento dos sistemas aquaticos. O conhecimento sobre esse assunto ainda e muito pouco explorado, especialmente no que se refere aos riachos da regiao Neotropical. Neste estudo, apresentamos os principais marcos teoricos, os diferentes metodos consagrados na literatura, bem como as perspectivas sobre o tema para peixes de riachos neotropicais. Destacamos que todos os metodos disponiveis conduzem a resultados semelhantes e a escolha de um ou outro recai sobre as circunstâncias da pesquisa. Para peixes de riachos tropicais recomendamos o uso do Metodo da Distribuicao de Tamanho. Apresentamos, tambem, um passo-a-passo para o uso do software R (pacote TropFishR) para os calculos de producao. Uma abordagem comparativa e realizada para as taxas de producao conhecidas em regioes de clima tropical, temperado e mediterrâneo, sugerindo-se um padrao inverso entre a diversidade de especies e as taxas de producao desses ambientes. Esperamos, com o presente estudo, estimular pesquisas nessa area do conhecimento, de forma a se incluir informacoes sobre os padroes e processos geradores de producao em riachos neotropicais em um contexto mais amplo da teoria ecologica. FISH PRODUCTION IN STREAMS: REVIEWING PRINCIPLES, METHODS AND PERSPECTIVES: Production studies are fundamental for understanding various aspects of the organization and functioning of aquatic systems. The current state of knowledge on this subject is still little explored, especially regarding streams in the Neotropical region. In this study, we present the main theoretical frameworks, the different methods available in the literature, as well as perspectives on the topic for fish from neotropical streams. We emphasize that all available methods lead to similar results and the choice of one or the other falls on the circumstances of the research. For tropical stream fish we recommend using the Size Distribution Method. We also present a step-by-step guide for using the R software (TropFishR package) for production calculations. A comparative approach is carried out for the known production rates in Tropical, Temperate and Mediterranean regions, suggesting an inverse pattern between the species diversity and the production rates of these environments. We hope, with the present study, to stimulate research in this area of knowledge, to include the patterns and processes that generate production in neotropical streams in a broader context of ecological theory.

Movimento e um fator chave da dinâmica espacial e do tamanho das populacoes de peixes. E um dos principais mecanismos para manter populacoes viaveis e tambem responde pela dispersao, colonizacao e execucao de etapas da vida dos individuos. O paradigma do movimento restrito, atualmente refutado, previa que peixes de agua doce nao se movimentam. Entretanto estudos mostram que, alem de se movimentar em curta e larga escala, os padroes de movimento desses peixes tem, em geral, motivacao reprodutiva, alimentar, busca por abrigo, colonizacao ou exploracao. Os estudos sobre movimento de peixes Neotropicais estao concentrados nos grandes migradores de grandes bacias, como Amazonas e Parana. Para riachos, onde predominam especies de pequeno porte, pouco ainda se sabe sobre o movimento e suas motivacoes. Nesta revisao mostramos que sao ainda bastante escassos os estudos sobre o movimento de peixes em riachos neotropicais. Propomos um protocolo para obtencao de dados e ferramentas analiticas para determinacao do movimento dos peixes em riachos. Destacamos tres ferramentas para essas analises: (i) analise da estrutura espaco-temporal do tamanho dos individuos, (ii) experimentos de marcacao-recaptura e (iii) analises moleculares. Concluimos que, dadas as limitacoes de cada analise, a utilizacao das tres ferramentas deveria ser realizada de forma conjunta. TITLE: ECOLOGY OF MOVEMENT IN STREAM-DWELLING FISH ABSTRACT Movement is a key factor in spatial dynamics and the size of fish populations. It is one of the main mechanisms for maintaining viable populations and also accounts for the dispersion, colonization and performance of individuals life stages. The currently refuted restricted movement paradigm predicted that freshwater fish would not move. However, studies show that in addition to moving on a short and large scale, the movement patterns of these fish have, in general, reproductive, food, search for shelter, colonization or exploitation motivation. Studies on the movement of Neotropical fish are concentrated on the large migrators from large basins, such as Amazonas and Parana. For streams, where small species predominate, little is known about the movement and its motivations. In this review, we show that studies on the movement of fish in neotropical streams are still very scarce. We propose a protocol for obtaining data and analytical tools for determining fish movement in streams. We highlight three tools for that: (i) analysis of the spatio-temporal structure of the size of the fish, (ii) mark-recapture experiments and (iii) molecular analyzes. We conclude that, given the limitation of each analysis, the use of the three tools must be carried out jointly.

O presente estudo mostra os avancos obtidos na coleta de peixes e caracterizacao ambiental de riachos. Desde a publicacao em 1999 do volume VI “Ecologia de Peixes de Riachos”, da entao denominada Oecologia Brasiliensis , hoje Oecologia Australis , varios progressos ocorreram. Diversos metodos de coleta de peixes propriamente ditos, permaneceram os mesmos. Porem, em relacao ao uso da pesca eletrica, coleta de ovos e larvas de peixes, e caracterizacao de habitat fisicos em riachos, houve notavel desenvolvimento e aperfeicoamento. O objetivo deste artigo e apresentar o “estado da arte” destes aspectos da amostragem de peixes e habitat em riachos. Metodos de preparo de amostras para analises geneticas, isotopos estaveis e metais pesados sao apresentados resumidamente ao final. ADVANCES IN METHODS FOR FISH SAMPLING AND HABITAT ASSESSMENT IN TROPICAL STREAMS: This paper brings some advances in fish data sampling and stream environments. Since the publication in 1999 of volume VI “Ecology of Stream Fishes” in the former Oecologia Brasiliensis journal, today Oecologia Australis , several progresses have occurred. Several methods of collecting fish themselves, have remained the same. However, in relation to the use of electric fishing, collection of eggs and fish larvae, and characterization of physical habitats in streams, there was remarkable development and improvement. The purpose of this article is to present the “state of the art” of these three aspects of sampling fish and habitats in streams. By the end, preparation methods of samples for genetic, stable isotopes and heavy metal analyses are briefly presented.

The effects of invaders on native species are usually tested using species mean trait values over long time scales. However, considering individual variation over short timescales can help us better understand the interaction between invaders and native species. We compared trophic traits of the non-native guppy (Poecilia reticulata) and the native Brazilian poeciliid Phalloceros harpagos using experiments simulating the early stages of an invasive process. We used short-term mesocosms to simulate an early invasion scenario, where the two species were placed together, and a pre-invasion scenario, where species were kept separated, and analyzed interspecific and intraspecific trophic variability. We also compared the foraging efficiency of species in laboratory experiments. We found no differences on the mean diet of both species between pre and early invasion treatments. At the individual level, in the early invasion scenario, individuals of both species reduced their trophic niche as a probable effect of the presence of the heterospecific. Phalloceros harpagos had higher consumption rates than guppies indicating greater efficiency in feeding on invertebrates. Our results suggest that non-native species were not intrinsically better consumers of high-quality resources. Instead, intraspecific variation might be playing an overlooked role in shaping interactions between species during the early stages of invasion.

Alien species often flourish and become invasive in urban ecosystems. How and why invaders succeed in urban systems is an important, yet poorly understood, question. We investigate whether the success of urban invaders is related to changes in species traits that enhance invasive potential. We also explore whether a trophic mechanism helps explain the success of invaders in urban systems. We use the guppy Poecilia reticulata, a globally distributed alien species that has invaded both urban and non‐urban systems, as our model.We first characterize the effect of urbanization on streams where guppies are present. We measure guppy invasion success using their population density and size‐frequency. Then we assess how traits that are related to the potential of guppies to invade (life history and condition) respond to urbanization. Next, we explore how urbanization affects the availability of food for guppies and their diets. We also test if the presence of other fish species grants biological resistance to invasion by dampening guppy invasive potential.We find that urban streams have high concentrations of ammonium and faecal coliforms, indicating contamination from sewage. On average, guppy populations from urban streams have 26× higher density and larger body sizes than non‐urban populations. Urban guppies are in better condition and have on average five more offspring than non‐urban guppies. Urbanization increases the availability and consumption of highly nutritious food (chironomid larvae) by guppies. We find a positive relationship between the consumption of chironomids and both fecundity and condition. The presence of other fish species in urban streams often has a negative but small effect on guppy traits and density.Our data suggest a relaxation of trade‐offs that shape life‐history traits which is related to increased food resources in urban streams. These indicate that urbanization enhances the invasive potential of guppies through a trophic mechanism that simultaneously increases reproduction and somatic investment. Such mechanism is likely widespread because chironomids are often highly abundant in urban systems. Thus, not only guppies but also other invasive species can take advantage of such a resource to invest in traits that enhance invasion success., This paper looks at how urbanization enhances the success of invaders by changing species traits. The authors find that urbanization provides high food quality and quantity, which allows invasive guppies to increase body size and condition, number of offspring and population density. This suggests that urbanization promotes a highly invasive phenotype.

O Parque Natural Municipal Bosque da Barra é uma Unidade de Conservação de Proteção Integral criada em 2003 e uma das mais visitadas do Município do Rio de Janeiro. Estudos prévios indicam que a lagoa da UC é artificial e o parque abrange ambientes de brejos, originais da restinga da Mata Atlântica. Suas águas são provenientes da chuva e do complexo lagunar de Jacarepaguá, onde ocorrem diversas espécies de peixes que colonizaram a lagoa do Bosque. Levantamentos realizados no início do ano 2000 revelaram a ocorrência de 12 espécies de peixes de água doce, pertencentes a 11 gêneros e 7 famílias: jeju (Hoplerythrinus unitaeniatus), traíra (Hoplias cf. malabaricus), tamboatá (Callichthys callichthys), barrigudinhos (Phalloptychus januarius e Poecilia vivipara), mussum (Synbranchus marmoratus), acará (Geophagus brasiliensis), tilápiado-Nilo (Oreochromis niloticus), tilápia-do-Congo (Coptodon rendalli) e peixe-dasnuvens (Notholebias minimus). Em 2015 uma importante estiagem afetou diversas regiões do Brasil e culminou na completa seca da lagoa do Bosque da Barra. Neste projeto temos como objetivo realizar um novo levantamento das espécies de peixes dessa área, com a finalidade de determinar que espécies ocorrem como consequência da recolonização a partir do mesmo estoque inicial de espécies disponíveis na Lagoa de Jacarepaguá. Estão previstas duas campanhas de amostragem, uma no período seco e outra no período chuvoso. A primeira campanha (seca) foi realizada em 4 de agosto de 2022. A área amostral foi subdividida em 4 sítios de amostragem, sendo eles: (1) porção do fundo da lagoa próxima da manilha que conecta a lagoa de Jacarepaguá, (2) a zona inundada presente na lateral da lagoa, (3) na porção da lagoa artificialmente escavada e (4) nos brejos dentro da floresta. Fizemos registros dos parâmetros físico e químicos, por meio de sondas multiparâmetro, para medição de: Temperatura, pH, OD, Condutividade, Salinidade e Sólidos dissolvidos. A amostragem de peixes utilizou 4 redes de espera, espalhadas em pontos equidistantes por 1 hora, 1 rede de arrastinho com esforço concentrado próximo às macrófitas aquáticas emersas e 5 puçás com esforços de 1 hora nas margens. Foi registrada a ocorrência de 5 espécies, pertencentes a 4 gêneros e 3 famílias: Acará (Geophagus brasiliensis), traíra (Hoplias malabaricus), barrigudinhos (Poecilia vivípara, Phalloptychus januarius), tilápia-do-Nilo (Oreochromis niloticus). Os resultados desse levantamento deverão auxiliar na avaliação do estado dos estoques originais nas Lagoas de Jacarepaguá e sua importância no processo de recolonização das lagoas do Bosque.

Parental care is a major feature in the evolution of life- history traits and appears highly associated with the trade-off between egg number and size. It has been a controversial issue in studies about reproductive strategy and is deemed to have evolved multiple times, both in aquatic and terrestrial taxa. To explore relationships between parental care and egg size, we examined 313 species of bony fishes, including 152 species with parental care and 161 species without parental care. We mapped parental care onto a maximum likelihood (ML) unrooted phylogeny and analysed egg size and numbers data set using a logistic regression. The phylogenetically controlled analyses revealed that parental care is dispersed along with the retrieved phylogeny and that at least four distinct lineages parallel evolved from non- parental care lineages to parental care ones. The results of the logistic regression highlighted that egg size can be used as a good predictor of parental care and that there is a strong and consistent threshold in egg size transition between parental and non- parental care fishes. We conclude that egg size predicts parental care in bony fish and that egg size distribution is polymodal within parental care species probably reflecting the variation in the amount of energy used for care. To advance the knowledge about the hypotheses raised in this study, it would be important to gather information about more species and their respective number and size of eggs and the presence/absence of parental care., The project was supported by FAPERJ E-26/201.583/2018 to RIR; by CNPq 301463/2017-4, FAPERJ CNE E-26/202.762/2018, Prociência/UERJ/SR2 and Capes PrInt 88887.511123/2020-00 to RM and CNPq to CRLA.

Diversity gradients are observed in various groups of organisms. For fishes in streams, the Water-Energy, Productivity and Temporal Heterogeneity hypotheses are considered the best combination to explain richness patterns. The relationship between species diversity and the variables that represent the hypotheses are generally considered linear and stationary, that is, there is equal relation of cause and effect along an entire geographical extension. The assumption of stationarity has not been tested or even observed in diversity gradients, thus producing imprecise models. Therefore, our goal is to quantify stationarity in the existing relationships between the ichthyofauna of streams and the Water-Energy, Productivity and Temporal Heterogeneity hypotheses using a Geographically Weighted Regression – GWR. In the proposed model, there is conspicuous absence of stationarity between fish species richness and the tested hypotheses. Furthermore, water-energy dynamics were observed as a possible metabolic restriction mechanism acting on the community structuring of stream fishes. This mechanism divides the fish fauna from the studied Brazilian watercourses in two regions: i) Amazonian, characterized by a stable climate and populations with little resistance to thermal variation; and ii) Central, featured by greater ranges of temperature and fish populations resistant to thermal variation.

This study aimed to characterize species composition and abundance of fish assemblages of low-order streams of the Machado River Basin and to identify the main environmental factors associated to fish assemblages along the elevational gradient. Fishes were collected by seine and dip nets, along an 80-m stretch of 71 streams. In each site, we recorded physical, chemical, and land–water ecotone variables. We collected 22,702 specimens of 91 species. Species richness and abundance varied negatively with elevation. Ordination and similarity analyses detected that streams located in higher and middle elevation ranges differed in species composition from those in the lower elevation range. Almost one-third of the recorded species were selected as indicator species. Species of the families Trichomycteridae, Cichlidae, Gymnotidae, and Characidae were closely associated with the land–water ecotone and structural characteristics of lower elevation range, whereas several other Characidae species were more abundant in middle elevation range, where aquatic vegetation cover and conductivity values were higher. By assuming that composition and relative abundance of fish respond to environmental changes, hydrological characteristics may be viewed as environmental filters for stream assemblages by ultimately selecting the pool of species able to reach for specific elevation ranges and meet their biological requirements.

This study investigates the effect of a predation gradient on the female life history traits of the poeciliid live-bearing fish Phalloceros harpagos from a tropical stream in Brazil. Females’ length at maturity, somatic dry mass, reproductive allotment and fecundity varied significantly among predation sites. Phalloceros harpagos from the high-predation site showed smaller size at maturity and somatic dry mass, greater reproductive allotment and higher fecundity than the nonpredation site. In all sites, we observed superfetation: pregnant females with two broods at different developmental stages. The presence of superfetation was not observed before in other congeneric species, and it may represent an additional independent evolutionary origin of superfetation in the fish family Poeciliidae. Matrotrophy, the postfertilisation maternal provisioning of nutrients to developing embryos throughout gestation, was observed in all three sites, with values of the matrotrophy index above two. The population under high predation pressure showed the highest degree of matrotrophy (embryos quadruplicate their dry mass during development) and the greatest percentage of females with superfetation (44.4%). Some life history traits responded more strongly to predators’ presence and others to predator density. These results suggest that different predation regimes shape female life history traits, increasing fecundity in high-predation sites. The results also suggest a link between the cost of reproduction and the evolution of matrotrophy and superfetation, potentially to reduce the risk of predation without reducing fecundity.

We aimed to evaluate the relationship between form and function of two Loricariidae species (Hypostomus punctatus and Parotocinclus maculicauda) from a Neotropical coastal stream. We performed morphological-dietary analysis and discussed their coexistence strategies, as well. We hypothesized that both species use similar food resources according to their morphology but differences in habitat use facilitate their coexistence. In order to test this hypothesis, morphology, diet and habitat use were analyzed for both species. Trophic variance and the Pianka Niche Overlap index were calculated to explore the differences in trophic niche. Correlations between species abundance and water flow were applied to test habitat use. Principal Component Analysis and one Permutational Multivariate Analysis of Variance were applied to test differences between morphology and diet of both species. Morphological-dietary relationships were tested with Mantel test correlations. Total abundance of H. punctatus was higher in the stream channel with higher water flow. The dominant food items were sediment and organic matter for both species, and high trophic niche overlap was revealed. Additionally, morphology did not explain feeding habits for both species. Morphological characteristics were significantly different, especially for intestine length, relative area of the dorsal fin, ventral flattening and mouth attributes. The study site was rich in sand sediment, mud, and clay that are not considered good substrates to the establishment and growing of periphyton, which is an important trophic resource to Loricariidae species. Here, low consumption of periphyton can provide a possible explanation for the feeding similarity and the weak morphological-dietary relationships for both species. Thus, the environmental conditions can be more important for diet composition when compared to the similar and specialized morphology of loricariids.

The current COVID-19 pandemics is a major threat to human populations. The disease has rapidly spread, causing mass hospitalization and the loss of millions of people mainly in urban areas which are hubs for contagion. At the same time, the social distancing practices required for containing the outbreak have caused an eruption of mental illnesses that include symptoms of depression, anxiety and stress. The severity of such mental distress is modulated by the context of media coverage and the information and guidelines from local health authorities. Different urban green infrastructures, such as gardens, parks, and green views can be important for mitigating mental distress during the pandemics. However, it is unclear whether some urban green infrastructures are more efficient than others in reducing mental distress or whether their effectiveness changes with the context. Here we assess the relative importance of different urban green infrastructures on the mental distress of residents of Rio de Janeiro, Brazil. We show that although urban parks and green views are important, home gardens are the most efficient in mitigating mental distress. This is likely related to the practice of self-isolation seen for the residents of Rio de Janeiro. Information on the efficiency of different urban green infrastructures in mitigating mental distress can be important to help guide programs to inform the public about the best practices for maintaining mental health during the current outbreak. This can also help planning cities that are more resilient to future pandemics.

The head morphology and feeding habits of pairs of characin species (family Characidae) that coexist in four different coastal rainforest streams were analysed. Coexisting species differed in size, but were very similar in eco-morphological attributes. Gut analyses revealed differences in feeding preferences for each coexisting species, indicating resource partitioning. A pattern of organization in species pairs that was repeated in the four studied streams was noticed. The pattern consisted of one slightly larger species with a feeding preference for items of allochthonous origin and another smaller species with a preference for autochthonous items. The hypothesis that small morphological differences enable the current coexistence of those species pairs was proposed. Furthermore, the results show ecological equivalence among different species in the studied streams.

The effects of riparian forest removal on a neotropical stream fish assemblage were assessed in the Mata Atlântica. Fish assemblage structure and fish feeding patterns were quantified at three sites along a pristine-to-deforested gradient in a Serra do Mar stream: (1) a pristine site fully covered by canopy with no light penetration and transparent waters, (2) an intermediate site with partially removed forest and (3) a fully removed forest site with no canopy and full light penetration where siltation and turbid waters predominate. Fish assemblage structure, fish densities and their feeding patterns differed widely among sites. Whilst the same five fish species occurred at the three sites, forest removal favoured the occurrence of sediment-tolerant iliophagous benthic species at the deforested site. At the pristine site, invertebrate prey predominated in water column fish diet and feeding overlap among species was low. Severe shifts in the feeding patterns were noticed in both deforested sites. Invertebrates were replaced by detritus, organic matter and algae at both sites and feeding overlap increased markedly. The overwhelming feeding adaptability of these neotropical fishes appeared capable of buffering the deleterious effects of forest removal on stream quality in terms of increased light penetration, siltation and water turbidity. Forest cutting in this Mata Atlântica stream clearly caused strong functional changes associated with forest clearance through important modifications in the assemblage organization and trophic patterns of the main species, but did not eliminate species.

The aim of this study was to elaborate a taxonomic survey on the testate amoebae of the Family Arcellidae in coastal streams in the State of Rio de Janeiro. Six samplings were conducted in Ubatiba coastal stream (Maricá, RJ). In total, 130 liters water were filtered through a conical net of 60-μm mesh and preserved in 4% formalin. Organisms were identified with the aid of an inverted trinocular microscope. The morphological characteristics (lobose testate amoebae with shell composed of granular chitinoid elements) of each species were recorded. The species were described and illustrated. For the verification of new taxa records of Arcellidae in Rio de Janeiro and their distribution in Brazil, a search based on index articles by Scopus, Web of Science and Google Scholar using the keywords "tecamebas", "testate amoebae", "Arcella", "Arcellidae", "Brazil" and "Rio de Janeiro", was performed. Eight Arcellidae species were recorded. Some ecological and taxonomic information was provided. Due to the small amount of information on testate amoebae, this study is important because it reduces the knowledge gap regarding this community in the State of Rio de Janeiro. Furthermore, we suggest new studies on species identification to be conducted to expand regional knowledge about these organisms. The aim of this study was to elaborate a taxonomic survey on the testate amoebae of the Family Arcellidae in coastal streams in the State of Rio de Janeiro. Six samplings were conducted in Ubatiba coastal stream (Maricá, RJ). In total, 130 liters water were filtered through a conical net of 60-μm mesh and preserved in 4% formalin. Organisms were identified with the aid of an inverted trinocular microscope. The morphological characteristics (lobose testate amoebae with shell composed of granular chitinoid elements) of each species were recorded. The species were described and illustrated. For the verification of new taxa records of Arcellidae in Rio de Janeiro and their distribution in Brazil, a search based on index articles by Scopus, Web of Science and Google Scholar using the keywords "tecamebas", "testate amoebae", "Arcella", "Arcellidae", "Brazil" and "Rio de Janeiro", was performed. Eight Arcellidae species were recorded. Some ecological and taxonomic information was provided. Due to the small amount of information on testate amoebae, this study is important because it reduces the knowledge gap regarding this community in the State of Rio de Janeiro. Furthermore, we suggest new studies on species identification to be conducted to expand regional knowledge about these organisms.

The removal of native forest affects stream characteristics, processes, and organisms at the local scale. We compared the structure of fish assemblages between microbasins impacted by deforestation and those in pristine condition in the Amazonian Machado River basin, Brazil. Fish were collected with seine and dip nets along an 80-m stretch of 28 streams. At each site, we recorded physical, chemical, and land-water ecotone variables. We collected 6,586 specimens of 109 species, being 39 and 18 of them exclusively of forested and deforested streams, respectively. Non-significant differences were found for abundance and species richness between forested and deforested streams. A total of four main trophic groups were identified. Carnivores were more abundant in forested streams, whereas herbivores, omnivores and detritivores species were the most abundant in deforested streams. The deforested streams showed higher abundance and richness of algae and periphyton consumers, while forested streams presented higher abundance and richness of invertebrate consumers. Forested streams presented longer foodchains, higher occurrence and abundance of species that have more specialized habits and are intolerant to degraded environments, whereas generalist and tolerant species predominated in deforested streams. We conclude that species composition in Amazonian streams predictably responds to the degree of forest cover.

Given the importance of fish movement to the dynamics and maintenance of stream dwelling fish communities from the Atlantic Forest, we analysed patterns of fish movement in a coastal stream from Southeastern Brazil, using mark-recapture technique. Displacement distance of each species were presented and discussed considering seasonal (rainy and dry) and body size patterns. We marked 10 species along the stream and recaptured 440 (34.6%) of the 1,270 marked fishes. The species with significant number of upstream moving individuals were Astyanax janeiroensis, Characidium interruptum, Astyanax hastatus, Parotocinclus maculicauda and Awaous tajasica. Only Pimelodella lateristriga presented significant differences between resident and moving individuals. Characidium interruptum and A. tajasica demonstrated greater downstream and upstream movement, respectively, moving up to 2,100 m. Even after controlling for species identity we found no significant correlation between fish length and individual displacement distance. Fishes moved longer distances during the rainy season, in accordance to the breeding season. Patterns of fish movement were in agreement to life-history traits of many of the studied species and can be reflecting specific behaviour and morphologies. RESUMO Considerando-se a importância do movimento de peixes para a dinâmica e manutenção das comunidades de peixes de riachos da mata Atlântica, nós analisamos os padrões de movimento de peixes de um riacho costeiro do sudeste do Brasil, usando a técnica da marcação e recaptura. Avaliamos a distância do deslocamento de cada espécie e também se os padrões de movimento apresentavam alguma relação com a estação do ano (chuva e seca) e o tamanho do corpo. Marcamos 10 espécies ao longo do riacho e recapturamos 400 (34.6%) dos 1.270 peixes marcados. As espécies com número significativo de indivíduos se movendo para cima foram Astyanax janeiroensis, Characidium interruptum, Astyanax hastatus, Parotocinclus maculicauda e Awaous tajasica. Apenas Pimelodella lateristriga apresentou diferenças significativas entre os indivíduos residentes e em movimento. Characidium interruptum e A. tajasica foram as espécies com maior movimento tanto para baixo como para cima, respectivamente, se movendo até mais de 2.100 m. Mesmo após controlar a identidade das espécies, não registramos correlação significativa entre o comprimento e a distância individual do deslocamento. Registramos maiores densidades de peixes se movendo para montante durante a época de chuvas, em coincidência com a estação reprodutiva. Os padrões de movimento registrados estão de acordo com os componentes da história de vida de várias das espécies estudadas, e podem estar refletindo componentes morfológicos e comportamentais específicos.

Made available in DSpace on 2018-11-30T03:55:49Z (GMT). No. of bitstreams: 0 Previous issue date: 2018-09-19 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Fundação de Amparo à Pesquisa do Estado de Minas Gerais (FAPEMIG) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Several hypotheses are used to explain species richness patterns. Some of them (e. g. species- area, species-energy, environment-energy, water-energy, terrestrial primary productivity, environmental spatial heterogeneity, and climatic heterogeneity) are known to explain species richness patterns of terrestrial organisms, especially when they are combined. For aquatic organisms, however, it is unclear if these hypotheses can be useful to explain for these purposes. Therefore, we used a selection model approach to assess the predictive capacity of such hypotheses, and to determine which of them (combined or not) would be the most appropriate to explain the fish species distribution in small Brazilian streams. We perform the Akaike's information criteria for models selections and the eigenvector analysis to control the special autocorrelation. The spatial structure was equal to 0.453, Moran's I, and require 11 spatial filters. All models were significant and had adjustments ranging from 0.370 to 0.416 with strong spatial component (ranging from 0.226 to 0.369) and low adjustments for environmental data (ranging from 0.001 to 0.119) We obtained two groups of hypothesis are able to explain the richness pattern (1) water-energy, temporal productivity-heterogeneity (AIC = 4498.800) and (2) water-energy, temporal productivity-heterogeneity and area (AIC = 4500.400). We conclude that the fish richness patterns in small Brazilian streams are better explained by a combination of Water-Energy + Productivity + Temporal Heterogeneity hypotheses and not by just one. Univ Fed Para UFPA, Lab Ictiol Altamira, Altamira, Para, Brazil Univ Estadual Maringa, Nucleo Pesquisas Limnol Ictiol & Aquicultura Nupe, Maringa, Parana, Brazil Univ Estadual Paulista UNESP, Lab Ictiol, Sao Jose Do Rio Preto, SP, Brazil Univ Paulista, Sorocaba, SP, Brazil Univ Estado Rio De Janeiro, Dept Ecol, Rio De Janeiro, RJ, Brazil Univ Fed Ceara, Dept Biol, Ctr Ciencias, Fortaleza, Ceara, Brazil Univ Fed Ceara, Inst Ciencias Mar LABOMAR, Fortaleza, Ceara, Brazil Univ Fed Rio Grande do Norte UFRN, Dept Bot Ecol & Zool, Ctr Biociencias, Natal, RN, Brazil Univ Fed Lavras UFLA, Dept Biol, Lavras, MG, Brazil UFT, Porto Nacl, Tocantins, Brazil Univ Fed Para UFPA, Inst Ciencias Biol, Belem, Para, Brazil INPA, Coordenacao Biodiversidade, Manaus, Amazonas, Brazil Univ Brasilia, Dept Zool, Brasilia, DF, Brazil Univ Fed Sao Carlos, Sorocaba, SP, Brazil Pontificia Univ Catolica Goias, Programa Mestrado Sociedade Tecnol & Meio Ambient, UNIEvangel, Goias Ctr Biol Aquat, Goiania, Go, Brazil UFES, Dept Ciencias Agr & Biol, Ctr Univ Norte Espirito Santo CEUNES, Sao Mateus, ES, Brazil Univ Estadual Paulista, Inst Biociencias, Botucatu, SP, Brazil Univ Fed Minas Gerais, Dept Genet Ecol & Evolucao, Inst Ciencias Biol, Belo Horizonte, MG, Brazil Univ Fed Goias, Dept Ecol, Inst Ciencias Biol, Campus 2 UFG, Goiania, Go, Brazil Univ Estadual Paulista UNESP, Lab Ictiol, Sao Jose Do Rio Preto, SP, Brazil Univ Estadual Paulista, Inst Biociencias, Botucatu, SP, Brazil CNPq: 457463/2012-0 CNPq: 552009/2011-3 CNPq: 471283/2006-1 CNPq: 304002/2014-3 FAPEMIG: 304002/2014-3

Life history traits of Phalloceros anisophallos from Corrego Andorinha, Ilha Grande (RJ, Brazil) were examined and the following parameters were evaluated: superfetation, matrotrophy, brood size, reproductive season, length–weight relationship, female weight and brood size relationship. Males were smaller and less abundant than females. According to the temporal variation of the gonadosomatic index, reproduction occurred throughout the year, with a reduction around April. We did not register superfetation among reproductive females, but there was significant increase of dry weight of developing embryos, indicating substantial matrotrophy. Such a combination of reproductive features seems to be rare in the family Poeciliidae but common in the genus Phalloceros. More studies on the other species of the genus are necessary to confirm this pattern.