257 research outputs found

    A Molecular Perspective on Systematics, Taxonomy and Classification Amazonian Discus Fishes of the Genus Symphysodon

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    With the goal of contributing to the taxonomy and systematics of the Neotropical cichlid fishes of the genus Symphysodon, we analyzed 336 individuals from 24 localities throughout the entire distributional range of the genus. We analyzed variation at 13 nuclear microsatellite markers, and subjected the data to Bayesian analysis of genetic structure. The results indicate that Symphysodon is composed of four genetic groups: group PURPLE—phenotype Heckel and abacaxi; group GREEN—phenotype green; group RED—phenotype blue and brown; and group PINK—populations of Xingú and Cametá. Although the phenotypes blue and brown are predominantly biological group RED, they also have substantial contributions from other biological groups, and the patterns of admixture of the two phenotypes are different. The two phenotypes are further characterized by distinct and divergent mtDNA haplotype groups, and show differences in mean habitat use measured as pH and conductivity. Differences in mean habitat use is also observed between most other biological groups. We therefore conclude that Symphysodon comprises five evolutionary significant units: Symphysodon discus (Heckel and abacaxi phenotypes), S. aequifasciatus (brown phenotype), S. tarzoo (green phenotype), Symphysodon sp. 1 (blue phenotype) and Symphysodon sp. 2 (Xingú group)

    Parental care of Chestnut-capped Puffbird Bucco macrodactylus on the middle Juruá River, Amazonas, Brazil

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    Chestnut-capped Puffbird Bucco macrodactylus, like other members of the Bucconidae family, nest in arboreal termitaria. Here we described a nest of the species, found in the floodplain of the Juruá River in December 2014. It was built inside an arboreal termite mound, 2.45 m above the ground. We determined the type and frequency of prey consumed by chicks over six days: during this time adults brought food to the nest 147 times. Prey included both vertebrates and invertebrates, though the most frequent were insects of the Order Orthoptera. Fledging may have been directly stimulated by a predation attempt made by a marsupial

    Description of the nest of two Thamnophilidae species in Brazilian Amazon

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    Many Thamnophilidae species have poorly known breeding. Here we describe the nests and eggs of two species, Epinecrophylla ornata from a terra firme forest, and Myrmotherula assimilis from a flooded forest in Brazil. Knowledge on the natural history of these species is important for future conservation strategies

    Mitochondrial DNA phylogeny of the family cichlidae: monophyly and fast molecular evolution of the neotropical assemblage

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    Abstract. A mitochondrial DNA (mtDNA) phylogeny of cichlid fish is presented for the most taxonomically inclusive data set compiled to date (64 taxa). 16S rDNA data establish with confidence relationships among major lineages of cichlids, with a general pattern congruent with previous morphological studies and less inclusive molecular phylogenies based on nuclear genes. Cichlids from Madagascar and India are the most basal groups of the family Cichlidae and sister to African–Neotropical cichlids. The cichlid phylogeny suggests drift-vicariance events, consistent with the fragmentation of Gondwana, to explain current biogeographic distributions. Important phylogenetic findings include the placement of the controversial genus Heterochromis basal among African cichlids, the South American genus Retroculus as th

    Coarse- and fine-scale patterns of distribution and habitat selection places an Amazonian floodplain curassow in double jeopardy

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    Patterns of habitat selection are influenced by local productivity, resource availability and predation risk. Species have taken millions of years to hone the macro- and micro-habitats they occupy, but these may now overlap with contemporary human threats within natural species ranges. Wattled Curassow (Crax globulosa), an endemic galliform species of the western Amazon, is threatened by both hunting and habitat loss, and is restricted to whitewater floodplain forests of major Amazonian rivers. In this study conducted along the Juruá River, Amazonas, Brazil, we quantified the ranging ecology and fine-scale patterns of habitat selection of the species. We estimated the home range size of C. globulosa using conventional VHF telemetry. To estimate patterns of habitat selection, we used geolocations of day ranges to examine the extent and intensity of use across the floodplain, which were then compared to a high-resolution flood-map of the study area. We captured two females and one male, which were monitored for 13 months between September 2014 and September 2015. Average home range size was 283 ha, based on the 95% aLoCoH estimator. Wattled Curassows selected areas of prolonged flood-pulses (6-8 months/year) and had a consistent tendency to be near open water, usually in close proximity to river banks and lakes, especially during the dry season. Amazonian floodplains are densely settled, and the small portions of floodplain habitat used by Wattled Curassows are both the most accessible to hunters and most vulnerable to deforestation. As a result, the geographic and ecological distribution of Wattled Curassows places them at much higher extinction risk at multiple spatial scales, highlighting the need to consider habitat preferences within their conservation strategy

    Reduction of genetic diversity of the Harpy Eagle in Brazilian tropical forests

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    Habitat loss and fragmentation intensify the effects of genetic drift and endogamy, reducing genetic variability of populations with serious consequences for wildlife conservation. The Harpy Eagle (Harpia harpyja) is a forest dwelling species that is considered near threatened and suffers from habitat loss in the forests of the Neotropical region. In this study, 72 historical and current samples were assessed using eight autosomal microsatellite markers to investigate the distribution of genetic diversity of the Harpy Eagle of the Amazonian and Atlantic forests in Brazil. The results showed that the genetic diversity of Harpy Eagle decreased in the regions where deforestation is intense in the southern Amazon and Atlantic Forest. © 2016 Banhos et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited

    A Multilocus Approach to Understanding Historical and Contemporary Demography of the Keystone Floodplain Species Colossoma macropomum (Teleostei: Characiformes)

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    We studied the natural populations of a flagship fish species of the Amazon, Colossoma macropomum which in recent years has been suffering from severe exploitation. Our aim was to investigate the existence or not of genetic differentiation across the wide area of its distribution and to investigate changes in its effective population size throughout its evolutionary history. We sampled individuals from 21 locations distributed throughout the Amazon basin. We analyzed 539 individuals for mitochondrial genes (control region and ATPase gene 6/8), generating 1,561 base pairs, and genotyped 604 individuals for 13 microsatellite loci obtaining, on average, 21.4 alleles per locus. Mean HE was 0.78 suggesting moderate levels of genetic variability. AMOVA and other tests used to detect the population structure based on both markers indicate that C. macropomum comprises a single and large panmitic population in the main channel of the Solimões-Amazonas River basin, on the other hand localities in the headwaters of the tributaries Juruá, Purus, Madeira, Tapajós, and localities of black water, showed genetic structure. The greatest genetic differentiation was observed between the Brazilian Amazon basin and the Bolivian sub-basin with restricted genetic flow between the two basins. Demographic analyzes of mitochondrial genes indicated population expansion in the Brazilian and Bolivian Amazon basins during the Pleistocene, and microsatellite data indicated a population reduction during the Holocene. This shows that the historical demography of C. macropomum is highly dynamic. Conservation and management strategies should be designed to respect the existing population structure and minimize the effects of overfishing by limiting fisheries C. macropomum populations

    Genomic resources for the conservation and management of the harpy eagle (Harpia harpyja, Falconiformes, Accipitridae)

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    We report the characterization and optimization of 45 heterologous microsatellite loci, and the development of a new set of molecular sex markers for the conservation and management of the Neotropical harpy eagle (Harpia harpyja L. 1758). Of the 45 microsatellites tested, 24 were polymorphic, six monomorphic, 10 uncharacterizable due to multiple bands and five did not amplify. The observed gene diversity of the analyzed sample of H. harpyja was low and similar to that of other threatened Falconiformes. While a high proportion of the microsatellite markers were highly variable, individuals of H. harpyja could be differentiated by a joint analysis of just three (p = 2.79 × 10-4) or four markers (p = 2.89 × 10-4). Paternity could be rejected with 95.23% and 97.83% probabilities using the same three and four markers, respectively. The sex determination markers easily and consistently differentiated males from females even with highly degraded DNA extracted from naturally shed feathers. The markers reported in this study potentially provide an excellent set of molecular tools for the conservation and management of wild and captive H. harpyja and they may also prove useful for the enigmatic Neotropical crested eagle (Morphnus guianensis Daudin 1800). Copyright by the Brazilian Society of Genetics

    Description of the nest of two Thamnophilidae species in Brazilian Amazon

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    Many Thamnophilidae species have poorly known breeding. Here we describe the nests and eggs of two species, Epinecrophylla ornata from a terra firme forest, and Myrmotherula assimilis from a flooded forest in Brazil. Knowledge on the natural history of these species is important for future conservation strategies. © 2016, Sociedade Brasileira de Ornitologia. All rights reserved

    Boto (Inia geoffrensis—Cetacea: Iniidae) aggregations in two provisioning sites in the lower Negro River—Amazonas, Brazil: are they related?

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    The Negro River currently has seven floating houses where tourists can feed and interact with botos, each with its own history of how these aggregations were formed. Some keepers say these groups are familial, even reporting individuals being born into the group. However, behavioral studies have shown that botos are solitary, only forming groups at feeding areas and during the mating season. In the present study we used 12 microsatellite and molecular sex markers to characterize relationships within and between two boto aggregations (ten and seven botos each) in the lower Negro River. Molecular sexing revealed that all botos sampled from both aggregations were males. This may be explained by habitat preference, as male botos are primarily found in the main channels of large rivers, whereas females prefer more protected areas, such as flooded forests and its channels and lakes. Most of the animals were unrelated within each aggregation, demonstrating that these aggregations are not normally formed due to kinship bonds, but are exclusively for feeding, as botos learn that these places provide easy access to food. This study provides important information that helps us understand how human interaction is affecting the social structure and behavior of these animals
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