Uso do grau de preferência alimentar para a caracterizaç ão da alimentação de peixes na APA de São Pedro e Analândia

We studied feeding habits of four fish species in two watershed at APA - Área de Proteção Ambiental (Area of Environmental Protection) in São Pedro and Analândia, State of São Paulo, southeastern Brazil. Feeding Preference Degree (FPD) was used to demonstrate the importance of each food item for the species of both basins. Feeding habits of both species of lambari was variable. The allochtonous items such as insects, autochtonous items, and vegetal material were very important, characterizing omnivory. The bagre (Rhamdia quelen) fed mainly on insects at the Jacaré-pepira Basin and also on fishes at the Corumbataí basin. The cascudo Hypostomus strigaticeps ingested autochtonous vegetal material and sediments at both basins.

Chromosomal characteristics and karyotype evolution of oxyopidae spiders (araneae, entelegynae)

We made a cytogenetic analysis of four species of Oxyopidae and compared it with the karyotype data of all species of this family. In Hamataliwa sp, the mitotic cells showed 2n♂ = 26+X 1X 2 and telocentric chromosomes. The 2n♂ = 28, which has been described for only one oxyopid spider, is the highest diploid number reported for this family. Peucetia species exhibited distinct karyotype characteristics, i.e., 2n♂ = 20+X 1X 2 in P. flava and 2n♂ = 20+X in P. rubrolineata, revealing interspecific chromosome variability within this genus. However, both Peucetia species exhibited telocentric chromosomes. The most unexpected karyotype was encountered in Oxyopes salticus, which presented 2n♂ = 10+X in most individuals and a predominance of biarmed chromosomes. Additionally, one male of the sample of O. salticus was heterozygous for a centric fusion that originated the first chromosomal pair and exhibited one supernumerary chromosome in some cells. Testicular nuclei of Hamataliwa sp and O. salticus revealed NORs on autosomal pairs, after silver impregnation. The majority of Oxyopidae spiders have their karyotype differentiated by both reduction in diploid number chromosome number and change of the sex chromosome system to X type; however, certain species retain the ancestral chromosome constitution 2n = 26+X1X2. The most remarkable karyotype differentiation occurred in O. salticus studied here, which showed the lowest diploid number ever observed in Oxyopidae and the second lowest registered for Entelegynae spiders. © FUNPEC-RP www.funpecrp.com.br.

Spermatogenesis of Zaprionus indianus and Zaprionus sepsoides (Diptera, Drosophilidae): Cytochemical, structural and ultrastructural characterization

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Investigação da prevalência da amebíase em escolares do município de Imperatriz-MA

A amebíase é uma infecção causada pela Entamoeba histolytica e considerada uma importante causa de morbi-mortalidade no mundo. Estudos relatam uma prevalência elevada da amebíase em regiões tropicais, principalmente em comunidades que vivem em precárias condições sanitárias. O estudo epidemiológico da amebíase tem sido reavaliado desde que a E. histolytica, forma patogênica, foi distinta da E. dispar, forma não patogênica. O objetivo desta pesquisa foi estimar a prevalência de E. histolytica na população de escolares da rede municipal da cidade de Imperatriz (MA). Realizou-se um estudo de corte transversal que envolveu 405 escolares. As amostras foram analisadas através de exame parasitológico, pelo método de sedimentação espontânea, para triagem das amostras positivas para o complexo E. histolytica/E .dispar. Os exames positivos para o complexo E. histolytica/E. dispar foram posteriormente submetidos à reação em cadeia da polimerase (PCR) para diferenciação das espécies. Na PCR foi utilizado para amplificação inicial de um fragmento de 1076 pb, um conjunto de primers externo E1 e E2, seguida por uma PCR Multiplex usando os primers Eh-L/Eh-R e Ed-L/Ed-R para amplificação da E. histolytica e E. dispar, respectivamente. Não foi diagnosticado pela PCR amostras positivas para E.histolytica. A prevalência da E. dispar na população de escolares foi de 2,7% (11/405). A PCR se mostrou importante ferramenta para o diagnóstico diferencial das Entamoebas. Porém, estudos de prevalência da amebíase devem ser impulsionados em população com características diferenciadas, a fim de contribuir de forma efetiva para definir a situação epidemiológica desta infecção na cidade de Imperatriz.

Spatial Variation in Morphometry in Vanzosaura rubricauda (Squamata, Gymnophthalmidae) from Open Habitats of South America and its Environmental Correlates

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Micromorfologia e anatomia floral das seções neotropicais de Bulbophyllum Thouars (Orchidaceae, Asparagales): considerações taxonômicas e evolutivas

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

First detection of Leishmania spp. DNA in Brazilian bats captured strictly in urban areas

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Development of SCAR molecular markers in Eucalyptus saligna and Eucalitus tereticornis

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Phylogeography of the neotropical Anopheles triannulatus complex (Diptera: Culicidae) supports deep structure and complex patterns

Abstract Background The molecular phylogenetic relationships and population structure of the species of the Anopheles triannulatus complex: Anopheles triannulatus s.s., Anopheles halophylus and the putative species Anopheles triannulatus C were investigated. Methods The mitochondrial COI gene, the nuclear white gene and rDNA ITS2 of samples that include the known geographic distribution of these taxa were analyzed. Phylogenetic analyses were performed using Bayesian inference, Maximum parsimony and Maximum likelihood approaches. Results Each data set analyzed septely yielded a different topology but none provided evidence for the seption of An. halophylus and An. triannulatus C, consistent with the hypothesis that the two are undergoing incipient speciation. The phylogenetic analyses of the white gene found three main clades, whereas the statistical parsimony network detected only a single metapopulation of Anopheles triannulatus s.l. Seven COI lineages were detected by phylogenetic and network analysis. In contrast, the network, but not the phylogenetic analyses, strongly supported three ITS2 groups. Combined data analyses provided the best resolution of the trees, with two major clades, Amazonian (clade I) and trans-Andean + Amazon Delta (clade II). Clade I consists of multiple subclades: An. halophylus + An. triannulatus C; trans-Andean Venezuela; central Amazonia + central Bolivia; Atlantic coastal lowland; and Amazon delta. Clade II includes three subclades: Panama; cis-Andean Colombia; and cis-Venezuela. The Amazon delta specimens are in both clades, likely indicating local sympatry. Spatial and molecular variance analyses detected nine groups, corroborating some of subclades obtained in the combined data analysis. Conclusion Combination of the three molecular markers provided the best resolution for differentiation within An. triannulatus s.s. and An. halophylus and C. The latest two species seem to be very closely related and the analyses performed were not conclusive regarding species differentiation. Further studies including new molecular markers would be desirable to solve this species status question. Besides, results of the study indicate a trans-Andean origin for An. triannulatus s.l. The potential implications for malaria epidemiology remain to be investigated.

Eutrophication causes speciation reversal in whitefish adaptive radiations

Species diversity can be lost through two different but potentially interacting extinction processes: demographic decline and speciation reversal through introgressive hybridization. To investigate the relative contribution of these processes, we analysed historical and contemporary data of replicate whitefish radiations from 17 pre-alpine European lakes and reconstructed changes in genetic species differentiation through time using historical samples. Here we provide evidence that species diversity evolved in response to ecological opportunity, and that eutrophication, by diminishing this opportunity, has driven extinctions through speciation reversal and demographic decline. Across the radiations, the magnitude of eutrophication explains the pattern of species loss and levels of genetic and functional distinctiveness among remaining species. We argue that extinction by speciation reversal may be more widespread than currently appreciated. Preventing such extinctions will require that conservation efforts not only target existing species but identify and protect the ecological and evolutionary processes that generate and maintain species.

Mycoplasma mycoides subsp. capri and Mycoplasma mycoides subsp. mycoides LC can be grouped into a single subspecies

Mycoplasma mycoides subsp. capri and Mycoplasma mycoides subsp. mycoides LC can be combined into one taxon on the basis of several contributions on both DNA sequence and protein analyses reported in the literature. Moreover, for the differentiation and identification of mycoplasmas of the "mycoides cluster", we investigated the rpoB gene, encoding the beta-subunit of the RNA polymerase. A segment of 527 bp of the rpoB gene was amplified from 31 strains of ruminant mycoplasmas by PCR. The nucleotide sequences were determined and aligned, and accurate genetic relationships were calculated. Cluster analysis of rpoB DNA allowed species differentiation within the "mycoides cluster" and confirmed that M. mycoides subsp. capri and M. mycoides subsp. mycoides LC cannot be distinguished from each other. "Mycoplasma mycoides subsp. capri" is proposed as a common name for both subspecies.

Genomic signatures of relaxed disruptive selection associated with speciation reversal in whitefish

Background: Speciation reversal: the erosion of species differentiation via an increase in introgressive hybridization due to the weakening of previously divergent selection regimes, is thought to be an important, yet poorly understood, driver of biodiversity loss. Our study system, the Alpine whitefish (Coregonus spp.) species complex is a classic example of a recent postglacial adaptive radiation: forming an array of endemic lake flocks, with the independent origination of similar ecotypes among flocks. However, many of the lakes of the Alpine radiation have been seriously impacted by anthropogenic nutrient enrichment, resulting in a collapse in neutral genetic and phenotypic differentiation within the most polluted lakes. Here we investigate the effects of eutrophication on the selective forces that have shaped this radiation, using population genomics. We studied eight sympatric species assemblages belonging to five independent parallel adaptive radiations, and one species pair in secondary contact. We used AFLP markers, and applied FST outlier (BAYESCAN, DFDIST) and logistic regression analyses (MATSAM), to identify candidate regions for disruptive selection in the genome and their associations with adaptive traits within each lake flock. The number of outlier and adaptive trait associated loci identified per lake were then regressed against two variables (historical phosphorus concentration and contemporary oxygen concentration) representing the strength of eutrophication. Results: Whilst we identify disruptive selection candidate regions in all lake flocks, we find similar trends, across analysis methods, towards fewer disruptive selection candidate regions and fewer adaptive trait/candidate loci associations in the more polluted lakes. Conclusions: Weakened disruptive selection and a concomitant breakdown in reproductive isolating mechanisms in more polluted lakes has lead to increased gene flow between coexisting Alpine whitefish species. We hypothesize that the resulting higher rates of interspecific recombination reduce either the number or extent of genomic islands of divergence surrounding loci evolving under disruptive natural selection. This produces the negative trend seen in the number of selection candidate loci recovered during genome scans of whitefish species flocks, with increasing levels of anthropogenic eutrophication: as the likelihood decreases that AFLP restriction sites will fall within regions of heightened genomic divergence and therefore be classified as FST outlier loci. This study explores for the first time the potential effects of human-mediated relaxation of disruptive selection on heterogeneous genomic divergence between coexisting species.

Landscape genetics of Phaedranassa herb. (Amaryllidaceae) in Ecuador

Speciation can be understood as a continuum occurring at different levels, from population to species. The recent molecular revolution in population genetics has opened a pathway towards understanding species evolution. At the same time, speciation patterns can be better explained by incorporating a geographic context, through the use of geographic information systems (GIS). Phaedranassa (Amaryllidaceae) is a genus restricted to one of the world’s most biodiverse hotspots, the Northern Andes. I studied seven Phaedranassa species from Ecuador. Six of these species are endemic to the country. The topographic complexity of the Andes, which creates local microhabitats ranging from moist slopes to dry valleys, might explain the patterns of Phaedranassa species differentiation. With a Bayesian individual assignment approach, I assessed the genetic structure of the genus throughout Ecuador using twelve microsatellite loci. I also used bioclimatic variables and species geographic coordinates under a Maximum Entropy algorithm to generate distribution models of the species. My results show that Phaedranassa species are genetically well-differentiated. Furthermore, with the exception of two species, all Phaedranassa showed non-overlapping distributions. Phaedranassa viridiflora and P. glauciflora were the only species in which the model predicted a broad species distribution, but genetic evidence indicates that these findings are likely an artifact of species delimitation issues. Both genetic differentiation and nonoverlapping geographic distribution suggest that allopatric divergence could be the general model of genetic differentiation. Evidence of sympatric speciation was found in two geographically and genetically distinct groups of P. viridiflora. Additionally, I report the first register of natural hybridization for the genus. The findings of this research show that the genetic differentiation of species in an intricate landscape as the Andes does not necessarily show a unique trend. Although allopatric speciation is the most common form of speciation, I found evidence of sympatric speciation and hybridization. These results show that the processes of speciation in the Andes have followed several pathways. The mixture of these processes contributes to the high biodiversity of the region.

Carapace dentition patterns, morphometrics and allozyme differentiation amongst two toothed freshwater crab species (Potamonautes warreni and P-unispinus) (Decapoda : Brachyura : Potamonautidae) from river systems in South Africa

The taxonomic relationship between two toothed South African river crabs, Potamonautes warreni and P. unispinus, is unclear. The problem stems from the widespread variation in carapace dentition patterns amongst P. warreni individuals over its biogeographic range, where single toothed individuals may appear similar in carapace morphology to P. unispinus. Ten populations of P. warreni and 18 populations of P. unispinus were collected and the morphometric and genetic differentiation between the two taxa quantified. Patterns of morphometric and genetic variation were examined using multivariate statistics and protein gel electrophoresis, respectively. Principal component analyses of carapace characters showed that the two species are morphologically indistinguishable. However, discriminate functions analyses and additional statistical results corroborate the morphological distinction between the two taxa. Allozyme electrophoresis of 17 protein coding loci, indicated a close genetic similarity between the two species (I = 0.92). A fixed allelic difference at one locus (LT-2) and extensive genetic variability at another locus (PGM-1) indicate that two gene pools are present and that the two taxa are genetically isolated. Intraspecific genetic I values for both species were > 0.97 and indicated no apparent genetic structuring on a micro or macro-geographic scale. The variation in carapace dentition among P. warreni populations possesses no genetic basis and may possibly toe the product of ecogenesis. The value of dentition patterns in the systematics of river crabs is discussed. Dentition patterns among river crab species appear to be conserved and reliable as species specific diagnostic markers, but should ideally be used in combination with other morphological data sets and genetic evidence.