Revisão sistemática e filogeografia de Deconychura longicauda (Aves - Dendrocolaptidae)

Os limites interespecíficos da espécie politípica Deconychura longicauda (Dendrocolaptidae) foram investigados por uma análise conjunta, incluindo caracteres moleculares, morfológicos e vocais. Um total de 1.108 pares de bases de genes mitocondriais Cit b e ND2 foram usados para construir hipóteses filogenéticas, ao passo que os caracteres morfológicos e vocais foram analisados com métodos estatísticos univariado e multivariado. Todas as árvores filogenéticas recuperadas indicam altos níveis de diferenciação genética e estrutura filogeográfica em Deconychura longicauda, com o reconhecimento de quatro grupos principais bem apoiados, geograficamente constituídos por aves (1) do centro de endemismo Guiana no nordeste da América do Sul (2), da bacia amazônica excluindo o escudo das Guianas (3), do sopé oriental dos Andes, e (4), trans-Andinas da América do Sul e América Central. O nível de divergência genética entre estes clados varia de 6-8% (entre as aves Guianenses, não-Guianenses, do sopé dos Andes e trans-Andinas). Embora os caracteres morfológicos contribuam pouco para a diagnose em Deconychura, o canto, por outro lado, consistetemente os distinguem. Nós recomendamos com base, principalmente, em sua diagnose molecular e vocal o desdobramento de D. longicauda nas seguintes espécies filogenéticas e biológicas: Deconychura longicauda, D. pallida, D. zimmeri, D. connectens, D. typica e um táxon ainda não nomeado, endêmico do sopé oriental dos Andes.

Variação morfológica e molecular de Typhlops reticulatus (Linnaeus, 1758) (Serpentes: Typhlopidae)

As serpentes atuais são tradicionalmente divididas em dois grupos: Alethinophidia, taxonômica e ecologicamente mais diverso e Scolecophidia, grupo de serpentes fossoriais popularmente conhecidas como cobras-cegas, sendo Typhlopidae a família que possui maior número de espécies. Em função do hábito fossorial, os Typhlopidae são pouco representados em coleções cientificas e a escassez de amostras de tecido tem sido um fator limitante para realização de estudos moleculares dessa família. Por isso aspectos da biologia evolutiva como modos de especiação, padrão de diversificação e estruturação geográfica que devido o hábito fossorial e a pouca diferenciação morfológica intra e interespecífica são ainda pouco entendidos. Esse trabalho teve como objetivo analisar a variação morfológica e molecular de Typhlops reticulatus. Para isso foram analisados 314 exemplares de Typhlops, sendo 192 de T. reticulatus. Para análise morfológica foram utilizados caracteres morfométricos, morfológicos (folidose, hemipênis e osteologia craniana). Nas análises moleculares foram sequenciados 21 amostras de T. reticulatus dos genes mitocondriais Coi e Cyt b de diferentes localidades. As árvores filogenéticas foram feitas usando os métodos de Máxima Parcimônia e Máxima Verossimilhança e as relações entre os grupos foram inferidos através de rede de haplótipos. Através da combinação de caracteres moleculares e morfológicos foi possível observar a presença de duas linhagens evolutivas distintas de T. reticulatus: uma ao norte do Rio Amazonas e outra ao sul, esta última descrita como nova espécie nesse trabalho. Durante a análise dos exemplares de Typhlops para esse trabalho foi possível identificar duas novas espécies: Typhlops sp nov. 1 presente no Estado do Maranhão e Typhlops sp nov. 2 proveniente de Manaus, Amazonas. Os resultados desse estudo corroboram a afirmação que espécies com ampla distribuição geográfica podem apresentar diversidade críptica considerável e uma história evolutiva mais complexa do que se imagina.

Estudos genéticos em raias do gênero Potamotrygon (Chondrichthyes: Myliobatiformes: Potamotrygonidae) na Bacia do Rio Paraná

Pós-graduação em Ciências Biológicas (Zoologia) - IBB

Pseudoplatystoma metaense and P. orinocoense (Siluriformes: Pimelodidae) from the Orinoco basin, Venezuela: cytogenetic and molecular analyses

The genus Pseudoplatystoma includes catfish species distributed throughout the fresh waters of South America. These species are important fisheries resources and play a significant ecological role due to their piscivorous and migratory habits. The taxonomy of this genus is still debated: traditionally, only three species have been recognised, but recently, this number was raised to eight. The validity of these eight morphospecies, however, was not confirmed by two subsequent molecular phylogenetic studies, which identified either five or four main clades. In this study, we focused on the two morphospecies restricted to the Orinoco basin, P. metaense and P. orinocoense, which have been assigned to either the same or different clades in previous studies. We carried out cytogenetic analyses to describe their unknown karyotypes and to look for cytotaxonomic markers. We also analysed their mitochondrial sequences in order to assign the sampled specimens to the previously identified molecular clades. The two presumptive species show similar karyotypes (2n=56, 42 biarmed and 14 uniarmed chromosomes) and cytogenetic features in terms of the constitutive heterochromatin distribution and the number and location of minor and major ribosomal genes. Thus, no species-specific chromosome markers could be identified. The analysis of cytochrome b and cytochrome oxidase I mitochondrial genes (carried out by retrieving all the mtDNA Pseudoplatystoma sequences available in GenBank) distributed the sampled specimens into two distinct molecular clades and confirmed the need to re-evaluate, by parallel morphological and molecular analyses, the monophyly of some lineages.

Filogeografia e estrutura populacional de Astyanax paranae (Pisces: Characidae) na Bacia do rio Paranapanema

Atualmente, crescentes esforços vêm sendo desenvolvidos no sentido de se caracterizar a ictiofauna Neotropical de riachos do ponto de vista taxonômico e sistemático, porém a estrutura genética destas populações ainda é pouco conhecida, sendo escassos os estudos sobre filogeografia dessa ictiofauna. Considerando que Astyanax paranae representa a única espécie do complexo scabripinnis na bacia do Alto rio Paraná, a ausência de dados moleculares populacionais e as evidências citogenéticas e morfológicas de que esta espécie não represente uma unidade monofilética, faz-se necessário um amplo estudo filogeográfico e filogenético em Astyanax paranae. O presente projeto teve como objetivo caracterizar a variabilidade genética em populações de Astyanax paranae e estabelecer as relações filogenéticas filogeográficas entre as linhagens mitocondriais na bacia do rio Paranapanema. As análises foram realizadas através da análise de sequências do DNA mitocondrial a partir do gene Citocromo B (cyt b) que foram completamente seqüenciados. Foram analisadas 8 populações de Astyanax paranae: 2 populações da bacia do rio Pardo, 1 Córrego Hortelã, 2 Véu de Noiva, Botucatu/SP; 4 populações da bacia do rio Tibagi, 1 população Maria da Serra/PR; 1 Ponta Grossa/PR, 1 Cambé/PR, 1 Castrolanda/PR; 1 população do rio Itapetiniga, rio Itapetininga, Itapetiniga/SP.; o número de indivíduos por população variou de 1 a 5. Como grupo externo foram analisados 1 população de Astyanax altiparanae com 3 indivíduos (Véu de Noiva pt2, Botucatu/SP); 1 população de Astyanax fasciatus com 5 indivíduos (região de Itapetiniga/SP) e 1 população de Astyanax bockmanni com 2 indivíduos (Véu de Noiva pt2, Botucatu/SP); num total de 39 indivíduos. Entre as...(Resumo completo, clicar acesso eletrônico abaixo)

Resistência a fungicidas estrobilurinas em populações de Pyricularia oryzae de áreas de trigo no Brasil

Pós-graduação em Agronomia - FEIS

Resistance to QoI fungicides Is widespread in brazilian populations of the wheat blast pathogen magnaporthe oryzae

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

Descrição de uma nova espécie de Rhodnius (Hemiptera, Reduviidae, Triatominae) da Amazônia

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Estudo do nível de infecção por Babesia bovis e Babesia bigemina em bovinos da raça Canchim naturalmente infestados com o carrapato Rhipicephalus (Boophilus) microplus

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

A relict new species of Oreobates (Anura, Strabomantidae) from the Seasonally Dry Tropical Forests of Minas Gerais, Brazil, and its implication to the biogeography of the genus and that of South American Dry Forests

A new species of Oreobates is described from Cavernas do Peruacu National Park, Januaria, Minas Gerais state, in the Atlantic Dry Forests of Brazil. The new species is distinguished from all other Oreobates by having the following combination of characters: large tympanum, discs broadly enlarged and truncate on Fingers III and IV, smooth dorsal skin, nuptial pads absent, snout subacuminate, and a very short pulsatile (2-3 pulses) single-noted advertisement call with dominant frequency of about 3150 Hz, and no harmonic structure. Molecular phylogenetic analyses using partial sequences of the mitochondrial genes cytochrome b (cyt b) and 16S using multiple outgroups recovered the new species within Oreobates and sister to O. heterodactylus. The latter species inhabits the Dry Forests of Mato Grosso (Cerrado) and Bolivia (Chiquitano forests), and is strictly associated to these habitats, which suggests a preterit connection between Chiquitano and Atlantic Dry Forests. The discovery of a new Oreobates in the Atlantic Dry Forest is of great importance for the conservation of these dry forests, as it is known only from this type of habitat.

Evolutionary Insights from Bat Trypanosomes: Morphological, Developmental and Phylogenetic Evidence of a New Species, Trypanosoma (Schizotrypanum) erneyi sp nov., in African Bats Closely Related to Trypanosoma (Schizotrypanum) cruzi and Allied Species

Parasites of the genus Trypanosoma are common in bats and those of the subgenus Schizotrypanum are restricted to bats throughout the world, with the exception of Trypanosoma (Schizotrypanum) cruzi that also infects other mammals and is restricted to the American Continent. We have characterized trypanosome isolates from Molossidae bats captured in Mozambique, Africa. Morphology and behaviour in culture, supported by phylogenetic inferences using SSU (small subunit) rRNA, gGAPDH (glycosomal glyceraldehyde 3-phosphate dehydrogenase) and Cyt b (cytochrome b) genes, allowed to classify the isolates as a new Schizotrypanum species named Trypanosoma (Schizotrypanum) erneyi sp. nov. This is the first report of a Schizotrypanum species from African bats cultured, characterized morphologically and biologically, and positioned in phylogenetic trees. The unprecedented finding of a new species of the subgenus Schizotrypanum from Africa that is closest related to the America-restricted Trypanosoma (Schizotrypanum) cruzi marinkellei and T. cruzi provides new insights into the origin and evolutionary history of T. cruzi and closely related bat trypanosomes. Altogether, data from our study support the hypothesis of an ancestor trypanosome parasite of bats evolving to infect other mammals, even humans, and adapted to transmission by triatomine bugs in the evolutionary history of T. cruzi in the New World. (c) 2012 Elsevier GmbH. All rights reserved.

Description of Rhodnius montenegrensis n. sp (Hemiptera: Reduviidae: Triatominae) from the state of Rondonia, Brazil

We present here a multisource approach that takes advantage of several disciplines to address a taxonomic issue. A triatomine related to Rhodnius robustus Larrousse, 1927 was recently found in the state of Rondonia, Brazil. The name Rhodnius montenegrensis n. sp. is suggested because it was found in the municipality of Monte Negro. The main differences between these two species can be detected in the female and male genitalia, but there are also noticeable differences in their eggs. Molecular analysis using PCR-RFLP technique and Bayesian inferences based on a fragment of the Cytochrome b (Cyt b) gene corroborated the morphological findings. We used this integrative approach to address the taxonomic decision for a new Rhodnius species and its relationship with others of this genus. Results obtained herein stress that morphology must be used as the major approach for obtaining phenotypic information, and molecular data should be taken as a complementary tool.

Characterization of the cytochrome P-450 drug metabolism system of LS174T human colon tumor cell line

The human colon tumor cell line, LS174T, has been shown to have four major components of the drug metabolizing system; cytochrome b$\sb5$ reductase, cytochrome b$\sb5$, cytochrome P450 reductase and cytochrome P450, by activity measurements, spectral studies and antibody cross-reactivity. Cytochrome P450IA1 is induced by benzanthracene in these cells as shown by activity with the specific substrate, ethoxyresorufin, cross-reactivity with rabbit antibodies to rat IA1, and by a hybridizing band on a Northern blot to a rat IA1 probe.^ Further, this system has proven responsive to various inducers and conditions of growth. The enzyme activities were found stable over limited cell passages with control values of 0.03 and 0.13 $\mu$mol/min/mg protein for NADPH and NADH cytochrome c (cyt c) reducing activity, 0.05 nmol cyt b$\sb5$ per milligram and 0.013 nmol cytochrome P450 per milligram of microsomal protein. Phenobarbital/hydrocortisone treatment showed a consistent, but not always significant increase in the NADPH and NADH cyt c reducing activity and benzanthracene treatment an increase in the NADH cyt c reducing activity. Delta-aminolevulinic acid (0.5mM) caused a significant decrease in the specific activity of all enzyme contents and activities tested.^ Finally, the cytochrome b$\sb5$ to cytochrome P450, by the coordinate induction of the cytochrome b$\sb5$ pathway by P450 inducers, by the high ratio of NADH to NADPH ethoxycoumarin deethylase activity in uninduced cell microsomes, and by the increase in NADH and NADPH ethoxycoumarin deethylase activity when the microsomes were treated with potassium cyanide, a desaturase inhibitor. ^

Prevalence of haemosporidians in a Neotropical endemic bird area

Haemosporidians are vector-transmitted intracellular parasites that occur in many bird species worldwide and may have important implications for wild bird populations. Surveys of haemosporidians have traditionally focused on Europe and North America, and only recently have they been carried out in the Neotropics, where the prevalence and impacts of the disease have been less studied and are not well understood. In this study we carried out a survey in the endemic bird area of the Sierra Nevada de Santa Marta (SNSM), an isolated coastal massif in northern Colombia that contains a large number of biomes and that is experiencing high rates of habitat loss. We sampled birds from 25 species at 2 different altitudes (1640 and 2100 m asl) and determined avian haemosporidian infection by polymerase chain reaction and sequencing a portion of the cytochrome b (cyt b) gene of the parasite. From the sampled birds, 32.1% were infected by at least 1 of 12 unique cyt b lineages of haemosporidian genera: Plasmodium, Leucocytozoon, Haemoproteus, and subgenus Parahaemoproteus. We found a higher prevalence of avian haemosporidians at low altitudes (1640 m asl). All endemic bird species we sampled had at least one individual infected with avian haemosporidians. We also found evidence of higher overall prevalence among endemic rather than nonendemic birds, suggesting higher susceptibility in endemic birds. Overall, our findings suggest a high haemosporidian species richness in the bird community of the SNSM. Considering the rate of habitat loss that this area is experiencing, it is important to understand how avian haemosporidians affect bird populations; furthermore, more exhaustive sampling is required to fully comprehend the extent of avian haemosporidian infection in the area.

Predicting the Dispersal Potential of an Invasive Polychaete Pest along a Complex Coastal Biome

Boccardia proboscidea is a recently introduced polychaete in South Africa where it is a notorious pest of commercially reared abalone. Populations were originally restricted to abalone farms but a recent exodus into the wild at some localities has raised conservation concerns due to the species’ invasive status in other parts of the world. Here, we assessed the dispersal potential of B. proboscidea by using a population genetic and oceanographic modeling approach. Since the worm is in its incipient stages of a potential invasion, we used the closely related Polydora hoplura as a proxy due its similar reproductive strategy and its status as a pest of commercially reared oysters in the country. Populations of P. hoplura were sampled from seven different localities and a section of the mtDNA gene, Cyt b and the intron ATPSa was amplified. A high resolution model of the coastal waters around southern Africa was constructed using the Regional Ocean Modeling System. Larvae were represented by passive drifters that were deployed at specific points along the coast and dispersal was quantified after a 12-month integration period. Our results showed discordance between the genetic and modeling data. There was low genetic structure (Φ = 0.04 for both markers) and no geographic patterning of mtDNA and nDNA haplotypes. However, the dispersal model found limited connectivity around Cape Point—a major phylogeographic barrier on the southern African coast. This discordance was attributed to anthropogenic movement of larvae and adult worms due to vectors such as aquaculture and shipping. As such, we hypothesized that cryptic dispersal could be overestimating genetic connectivity. Though wild populations of B. proboscidea could become isolated due to the Cape Point barrier, anthropogenic movement may play the critical role in facilitating the dispersal and spread of this species on the southern African coast.