12 research outputs found

    Redescription of Anopheles (Nyssorhynchus) antunesi Galvão & Amaral and description of a new species of the Myzorhynchella Section (Diptera: Culicidae) from Serra da Mantiqueira, Brazil

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    Anopheles (Nyssorhynchus) pristinus Nagaki & Sallum, n. sp. of the Myzorhynchella Section is described based on morphological characters of adult females, males, fourth-instar larvae, pupae and male genitalia. Anopheles (Nyssorhynchus) antunesi Galvão & Amaral is characterized to fix its identity and distinguish it from An. pristinus. The eggs of An. antunesi are described for the first time. Molecular characterization employing sequences of the COI mitochondrial gene and the ITS2 region of ribosomal DNA are provided for each species. An. antunesi and An. pristinus are compared with morphologically similar species of the Myzorhynchella Section. The results of the present study suggest that the new species has been misidentified as both An. antunesi and Anopheles lutzii Cruz. An. antunesi and An. pristinus are sympatric, occurring at high altitudes in Serra da Mantiqueira, southeastern BrazilFAPESP 2005/53973-0, 07/01870-8, CNPq 300351/2008-

    Molecular phylogeny of the Myzorhynchella Section of Anopheles (Nyssorhynchus) (Diptera: Culicidae): genetic support for recently described and resurrected species

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    Phylogenetic relationships among species of the Myzorhynchella Section of Anopheles (Nyssorhynchus) were investigated using the nuclear ribosomal DNA second internal transcribed spacer (ITS2), the nuclear whitegene and mitochondrial cytochrome oxidase subunit I (COI) regions. The recently described Anopheles pristinus and resurrected Anopheles guarani were also included in the study. Bayesian phylogenetic analyses found Anopheles parvus to be the most distantly related species within the Section, a finding that is consistent with morphology. An. pristinus and An. guarani were clearly resolved from Anopheles antunesi and Anopheles lutzii, respectively. An. lutzii collected in the same mountain range as the type locality were found within a strongly supported clade, whereas individuals from the southern state of Rio Grande do Sul, tentatively identified as An. lutzii based on adult female external morphology, were distinct from An. lutzii, An. antunesi and from each other, and may therefore represent two new sympatric species. A more detailed examination of An. lutzii sensu latoalong its known geographic range is recommended to resolve these anomalous relationships.FAPESPCNP

    Brazilian mosquito (Diptera: Culicidae) fauna: I. Anopheles species from Porto Velho, Rondônia state, western Amazon, Brazil

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    Este estudo contribui para o conhecimento de espécies de Anopheles, incluindo vetores de Plasmodium do oeste da Amazônia brasileira, em Porto Velho, no estado de Rondônia. Esta região vem passando por mudanças ambientais, como consequência de agricultura extensiva e projetos hidroelétricos que causam desmatamento, favorecendo o desenvolvimento de algumas espécies de mosquitos. Assim, a proposta deste estudo é registrar a presença de espécies de anofelinos na área, sendo conduzidas coletas de mosquitos em três locais, ao longo de uma linha de transmissão de energia elétrica. Cada uma das localidades foi amostrada três vezes, no período de 2010 a 2011. Os principais mosquitos adultos capturados em armadilhas de Shannon foram Anopheles darlingi, An. triannulatus, An. nuneztovari l.s., An.gilesi e An. costai. Assim como as formas larvárias Anopheles braziliensis, An. triannulatus, An. darlingi, An. deaneorum, An. marajoara, An. peryassui, An. nuneztovari l.s. e An. oswaldoi-konderi, coletadas em criadouros. Anopheles darlingi foi a espécie mais coletada na região. Em adição, discutiu-se sistemática de Culicidae, distribuição de fauna e aspectos da malária em ambientes modificados do oeste da Amazônia brasileira.This study contributes to knowledge of Anopheles species, including vectors of Plasmodium from the western Brazilian Amazon in Porto Velho, Rondônia State. The sampling area has undergone substantial environmental changes as a consequence of agricultural and hydroelectric projects, which have caused intensive deforestation and favored habitats for some mosquito species. The purpose of this study was to diagnose the occurrence of anopheline species from collections in three locations along an electric-power transmission line. Each locality was sampled three times from 2010 to 2011. The principal adult mosquitoes captured in Shannon trap were Anopheles darlingi, An. triannulatus, An. nuneztovari l.s., An.gilesi and An. costai. In addition, larvae were collected in ground breeding sites for Anopheles braziliensis, An. triannulatus, An. darlingi, An. deaneorum, An. marajoara, An. peryassui, An. nuneztovari l.s. and An. oswaldoi-konderi. Anopheles darlingi was the most common mosquito in the region. We discuss Culicidae systematics, fauna distribution, and aspects of malaria in altered habitats of the western Amazon

    Taxonomic review and phylogeny of Myzorhynchella Section of Anopheles (Nyssorhynchus) (Diptera: Culicidae).

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    Anopheles é o gênero da família Culicidae mais estudado devido sua importância médica. Atualmente o gênero Anopheles compreende 472 espécies válidas que estão divididas em sete subgêneros. Os principais vetores de plasmódio da Malária no Brasil pertencem ao subgênero Nyssorhynchus, que inclui 39 espécies oficialmente reconhecidas e um número crescente de complexos de espécies crípticas que estão distribuídas em três Seções: Myzorhynchella, Albimanus e Argyritarsis. Atualmente a Seção Myzorhynchella é formada por seis espécies: An. lutzii, An. parvus, An. nigritarsis, An. guarani, An. antunesi e An. pristinus. Para o desenvolvimento da análise morfológica, observou-se material-tipo depositado em diferentes coleções, espécimes depositados na coleção entomológica da FSP/USP, além de outros obtidos em coletas realizadas durante o presente estudo em diferentes localidades do Brasil. As análises moleculares foram desenvolvidas a partir de espécimes obtidos nas coletas. Revisão taxonômica da Seção Myzorhynchella é apresentada, incluindo-se descrições de quatro novas espécies e redescrições das demais, informações sobre bionomia, importância médica, caracterização molecular, distribuição geográfica, estado de preservação do material-tipo, além de chaves de identificação de adultos, larva de quarto estádio e genitália masculina. Os resultados das análises filogenéticas utilizando sequências de ITS2, COI e Catalase indicam a existência de pelo menos doze espécies dentro da Seção Myzorhynchella, os espécimes que vêm sendo identificados como An. antunesi constitui um complexo formado por possíveis cinco espécies e aqueles de An. parvus e An. pristinus também podem representar complexos de espécies. As sequências de ITS2 podem ser utilizadas como marcador diagnóstico para espécies da Seção Myzorhynchella. Contudo, o estudo ainda demonstra que pouco se conhece sobre a diversidade de espécies de Anopheles que ocorrem em ambientes onde a malária ocorre em baixa endemicidade. Pelo número de espécies novas encontradas e pela escassez de trabalhos com espécies da Seção, fica evidente a necessidade de mais estudos.Anopheles is the Culicidae Family genus most studied because of its medical importance. The genus currently comprises 472 valid species that are divided into seven subgenus. The main vectors of plasmodium malaria in Brazil belong to the subgenus Nyssorhynchus, that includes 39 valid species and a growing number of cryptic species complexes that are divided in three Sections: Myzorhynchella, Albimanus and Argyritarsis. Myzorhynchella Section currently consists of six species: An. lutzii, An. parvus, An. nigritarsis, An. guarani, An. antunesi and An. pristinus. For the morphological analysis, type material deposited in different collections were studied, specimens deposited in the entomological collection of FSP/USP, and other obtained from field collections in different localities in Brazil during this study. The molecular analyzes were taken from specimens obtained in field collections. Taxonomic review of Myzorhynchella Section is presented, including descriptions of four new species and redescriptions of the others, information on bionomics, medical importance, molecular characterization, geographical distribution, preservation status of type material, as well as identification keys of adults, fourth instar larvae and male genitalia. The results of phylogenetic analysis using sequences of ITS2, COI and Catalase indicate the existence of at least twelve species within Myzorhynchella Section, the specimens which have been identified as An. antunesi is a species complex formed by possible five species and those of An. parvus and An. pristinus may also represent species complexes. The ITS2 sequences can be used as a diagnostic marker for species of Myzorhynchella Section. However, the study also shows that little is known about the diversity of Anopheles species that occur in environments where malaria occurs in low endemicity. By the number of new species found and the lack of studies with species of the Section, it is evident the need for further studies

    Systematic studies on species of Myzorhynchella section of the subgenus Nyssorhynchus (Diptera: Culicidae)

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    Introdução Anopheles (Nsssorhynchus) constitui o grupo de anofelinos que encerra o maior número de vetores de plasmódios que causam a malária humana na Região Neotropical. Em vista disso, são as espécies que têm sido mais frequentemente estudadas. O subgênero possui 33 espécies e está dividido em três seções, Myzorhynchella, Albimanus e Argyritarsis. A última revisão da seção Myzorhynchella é a de Galvão (1941) e são raros os estudos com a seção que é formada pelas espécies An. lutzii, An. parvus, An. nigritarsis e An. antunesi. Embora estas espécies sejam consideradas zoofílicas, estudos taxonômicos são necessários para estabelecer a identificação morfológica e para diferenciar estas espécies de outros Anophelinae, fornecendo assim condições adequadas para avaliar as espécies que estão envolvidas na transmissão da malária. Objetivos Caracterizar morfologicamente e molecularmente as espécies da seção Myzorhynchella e estabelecer caracteres morfológicos que permitam a separação entre as mesmas. Métodos Foram realizadas coletas de mosquitos em diferentes localidades da Mata Atlântica, além da análise de caracteres morfológicos de larva, pupa, adultos macho e fêmea e ovos de espécimes disponíveis na coleção entomológica da Faculdade de Saúde Pública FSP/USP, do Museu de Zoologia MZUSP e do Instituto Oswaldo Cruz IOC. Foram realizadas análises moleculares utilizando sequências de bases nucleotídicas da região do Espaçador Interno Transcrito 2 - ITS2 do DNA ribossômico e do gene mitocondrial Citocromo Oxidase Subunidade I - COI. Resultados - Foram caracterizados os adultos, machos e fêmeas, as formas imaturas e os ovos de An. antunesi e de An. lutzii. Anopheles guarani e An. niger foram retiradas da sinonímia de An. lutzii. Foi descrita uma espécie nova que é encontrada em simpatria com An. antunesi na Serra da Mantiqueira. Os resultados das análises filogenéticas corroboraram a existência de pelo menos cinco espécies dentro da seção Myzorhynchella e indicam que An. parvus e An. antunesi podem representar complexos de espécies. Acresce considerar que An. lutzii foi redescrita com o emprego de espécimes do Vale do Ribeira. No entanto, a falta de espécimes de An. lutzii da localidade tipo com as formas adultas e imaturos associados, impediram a caracterização adequada da espécie. Conclusão Foram caracterizadas quatro espécies da seção Myzorhynchella, foi descrita uma espécie nova que ocorre na Serra da Mantiqueira e demonstrou-se que An. parvus e An. antunesi podem ser complexos de espécies. Há a necessidade de continuar os estudos da Seção Myzorhynchella e obter topotipos de An. lutziiIntroduction Anopheles (Nsssorhynchus) is the group of anophelines that has the largest number of vectors of plasmodium that causes human malaria in the Neotropics. Because of this, species of this subgenus have been most frequently studied. The subgenus has 33 nominal species, subdivided into three sections, Myzorhynchella, Albimanus and Argyritarsis. The last revision on species of the Myzorhynchella section is that by Galvão (1941) and taxonomic studies are rare in the section that is formed by An. lutzii, An. parvus, An. nigritarsis and An. antunesi. Although these species are considered to be zoophilic, taxonomic studies are necessary to fix the morphological identification, and to differentiate these species from other Anophelinae, thus providing appropriate conditions to evaluate which species are involved in the transmission of malaria. Objetives To fix the morphological and molecular identification of species of the Myzorhynchella section and to define morphological characters to separate the species. Methods The mosquitoes were collected in different localities in the Mata Atlântica. These specimens were employed in analyses of morphological characters of eggs, larva, pupa, adult male and female, and were compared to specimens deposited in the Entomological Collection of Faculdade de Saúde Pública FSP/USP, Museu de Zoologia MZUSP and Instituto Oswaldo Cruz IOC. Molecular analysis were performed using sequences of of the internal transcribed spacer 2 ITS2 of ribosomal DNA and the mitochondrial cytochrome oxidase subunit I gene COI. Results We characterized the adults, male and female, immature forms and the eggs of An. antunesi and An. lutzii. Anopheles guarani and An. niger were removed from the synomym of An. lutzii. A new species that was found in sympatry with An. antunesi in Serra da Mantiqueira was described. Results of phylogenetic analysis corroborate the existence of at least five species within Myzorhynchella Section and indicate that An. parvus and An. antunesi may represent complexes of species. Besides An. lutzii was redescribed using specimens of Ribeira Valley. However, the lack of specimens of An. lutzii from the type locality with associated adults and immature forms prevented the proper characterization of the species. Conclusion We characterized four species of Myzorhynchella section, a new species that occurs in Serra da Mantiqueira was described, and it showed that An. parvus and An. antunesi may be species complex. There is a need to continue the studies of the section and get topotypes of An. lutzi

    Malaria vectors in South America: current and future scenarios

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    Abstract Background Malaria remains a significant public health issue in South America. Future climate change may influence the distribution of the disease, which is dependent on the distribution of those Anopheles mosquitoes competent to transmit Plasmodium falciparum. Herein, predictive niche models of the habitat suitability for P. falciparum, the current primary vector Anopheles darlingi and nine other known and/or potential vector species of the Neotropical Albitarsis Complex, were used to document the current situation and project future scenarios under climate changes in South America in 2070. Methods To build each ecological niche model, we employed topography, climate and biome, and the currently defined distribution of P. falciparum, An. darlingi and nine species comprising the Albitarsis Complex in South America. Current and future (i.e., 2070) distributions were forecast by projecting the fitted ecological niche model onto the current environmental situation and two scenarios of simulated climate change. Statistical analyses were performed between the parasite and each vector in both the present and future scenarios to address potential vector roles in the dynamics of malaria transmission. Results Current distributions of malaria vector species were associated with that of P. falciparum, confirming their role in transmission, especially An. darlingi, An. marajoara and An. deaneorum. Projected climate changes included higher temperatures, lower water availability and biome modifications. Regardless of future scenarios considered, the geographic distribution of P. falciparum was exacerbated in 2070 South America, with the distribution of the pathogen covering 35-46 % of the continent. As the current primary vector An. darlingi showed low tolerance for drier environments, the projected climate change would significantly reduce suitable habitat, impacting both its distribution and abundance. Conversely, climate generalist members of the Albitarsis Complex showed significant spatial and temporal expansion potential in 2070, and we conclude these species will become more important in the dynamics of malaria transmission in South America. Conclusions Our data suggest that climate and landscape effects will elevate the importance of members of the Albitarsis Complex in malaria transmission in South America in 2070, highlighting the need for further studies addressing the bionomics, ecology and behaviours of the species comprising the Albitarsis Complex
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