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1.
Parasit Vectors ; 12(1): 477, 2019 Oct 14.
Article in English | MEDLINE | ID: mdl-31610813

ABSTRACT

BACKGROUND: The Asian tiger mosquito, Aedes (Stegomyia) albopictus (Skuse) is an important worldwide invasive species and can be a locally important vector of chikungunya, dengue and, potentially, Zika. This species is native to Southeast Asia where populations thrive in both temperate and tropical climates. A better understanding of the population structure of Ae. albopictus in Lao PDR is very important in order to support the implementation of strategies for diseases prevention and vector control. In the present study, we investigated the genetic variability of Ae. albopictus across a north-south transect in Lao PDR. METHODS: We used variability in a 1337-bp fragment of the mitochondrial cytochrome c oxidase subunit 1 gene (cox1), to assess the population structure of Ae. albopictus in Lao PDR. For context, we also examined variability at the same genetic locus in samples of Ae. albopictus from Thailand, China, Taiwan, Japan, Singapore, Italy and the USA. RESULTS: We observed very high levels of genetic polymorphism with 46 novel haplotypes in Ae. albopictus from 9 localities in Lao PDR and Thailand populations. Significant differences were observed between the Luangnamtha population and other locations in Lao PDR. However, we found no evidence of isolation by distance. There was overall little genetic structure indicating ongoing and frequent gene flow among populations or a recent population expansion. Indeed, the neutrality test supported population expansion in Laotian Ae. albopictus and mismatch distribution analyses showed a lack of low frequency alleles, a pattern often seen in bottlenecked populations. When samples from Lao PDR were analyzed together with samples from Thailand, China, Taiwan, Japan, Singapore, Italy and the USA, phylogenetic network and Bayesian cluster analysis showed that most populations from tropical/subtropical regions are more genetically related to each other, than populations from temperate regions. Similarly, most populations from temperate regions are more genetically related to each other, than those from tropical/subtropical regions. CONCLUSIONS: Aedes albopictus in Lao PDR are genetically related to populations from tropical/subtropical regions (i.e. Thailand, Singapore, and California and Texas in the USA). The extensive gene flow among locations in Lao PDR indicates that local control is undermined by repeated introductions from untreated sites.


Subject(s)
Aedes/physiology , Mosquito Vectors/physiology , Aedes/classification , Aedes/genetics , Aedes/virology , Algorithms , Animals , Asia, Southeastern , Bayes Theorem , Cluster Analysis , DNA/chemistry , DNA/isolation & purification , Electron Transport Complex IV/genetics , Asia, Eastern , Female , Genetic Variation , Genetics, Population , Haplotypes , Italy , Laos , Mitochondria/enzymology , Mosquito Control , Mosquito Vectors/classification , Mosquito Vectors/genetics , Mosquito Vectors/virology , Phylogeny , Sequence Analysis, DNA , Tropical Climate , United States
2.
Infect Genet Evol ; 12(6): 1246-52, 2012 Aug.
Article in English | MEDLINE | ID: mdl-22522004

ABSTRACT

We undertook geometric morphometric analysis of wing venation to assess this character's ability to distinguish Anopheles darlingi Root populations and to test the hypothesis that populations from coastal areas of the Brazilian Atlantic Forest differ from those of the interior Atlantic Forest, Cerrado, and the regions South and North of the Amazon River. Results suggest that populations from the coastal and interior Atlantic Forest are more similar to each other than to any of the other regional populations. Notably, the Cerrado population was more similar to that from north of the Amazon River than to that collected of south of the River, thus showing no correlation with geographical distances. We hypothesize that environmental and ecological factors may affect wing evolution in An. darlingi. Although it is premature to associate environmental and ecological determinants with wing features and evolution of the species, investigations on this field are promising.


Subject(s)
Anopheles/anatomy & histology , Insect Vectors/anatomy & histology , Wings, Animal/anatomy & histology , Animals , Brazil , Ecosystem , Female , Male , Organ Size , Reproducibility of Results
3.
São Paulo; s.n; 2012. 121 p.
Thesis in Portuguese | LILACS | ID: lil-643301

ABSTRACT

Introdução - A malária é uma das principais doenças humanas do mundo e afeta principalmente as populações pobres em regiões tropicais e subtropicais onde as condições ambientais são favoráveis tanto para a proliferação dos agentes etiológicos como dos mosquitos vetores. No Brasil, An. darlingi é considerado vetor primário de plasmódios humanos. Devido à importância médica, esse inseto tem sido objeto de campanhas de controle populacional. No entanto, não foi considerada a ocorrência de microevolução em An. darlingi e consequentemente, a possibilidade de populações diferentes apresentarem características biológicas distintas. Objetivo Verificar a presença de variabilidade genética e morfológica em populações de An. darlingi no Brasil. Metodologia - Foram analisados e comparados 26 atributos da morfologia externa de ovos de nove populações, bem como a morfometria geométrica da forma alar de espécimes de 10 localidades diferentes de Anopheles darlingi. Além disso, foram empregadas sequências do gene mitocondrial citocromo oxidase subunidade I (COI) para analisar a estrutura populacional de An. darlingi. Resultados e Conclusão Apesar dos atributos dos ovos apresentarem variação, somente as amostras de Tocantins e Pará foram diferenciadas das demais populações. As variações nas estruturas externas dos ovos são provavelmente adaptativas, com influência de fatores ambientais, como temperatura, umidade e disponibilidade de alimento para as fêmeas. A comparação da morfometria geométrica da asa demonstrou que existe maior similaridade entre as populações da costa (estados do Espírito Santo , do cerrado (estados de Goiás e Tocantins), do norte do rio Amazonas (estados do Amazonas e Amapá), e do sul do rio Amazonas (estados de Mato Grosso e Pará).


Subject(s)
Animals , Anopheles/anatomy & histology , Anopheles/genetics , Insect Vectors/anatomy & histology , Insect Vectors/genetics , Brazil , Electron Transport Complex IV/genetics , Wings, Animal/anatomy & histology , Zygote/ultrastructure
4.
J Am Mosq Control Assoc ; 27(3): 191-200, 2011 Sep.
Article in English | MEDLINE | ID: mdl-22017082

ABSTRACT

We analyzed nuclear (second internal transcribed spacer and white gene) and mitochondrial (cytochrome c oxidase subunit I) data from Anopheles konderi collected in the Amazonian states of Acre, Amapá, and Rondônia and the southern Brazilian state of Paraná. This was the first record of An. konderi in the state of Paraná. We found a high degree of genetic divergence within the Amazonian region and support for An. konderi as a species complex, possibly consisting of 3 species.


Subject(s)
Anopheles/genetics , Animals , Anopheles/classification , Brazil , DNA, Ribosomal Spacer/genetics , Electron Transport Complex IV/genetics , Female , Male , Phylogeny
5.
Mem Inst Oswaldo Cruz ; 104(6): 823-50, 2009 Sep.
Article in English | MEDLINE | ID: mdl-19876554

ABSTRACT

The Anopheles (Nyssorhynchus) albitarsis complex includes six species: An. albitarsis, Anopheles oryzalimnetes Wilkerson and Motoki, n. sp., Anopheles marajoara, Anopheles deaneorum, Anopheles janconnae Wilkerson and Sallum, n. sp. and An. albitarsis F. Except for An. deaneorum, species of the complex are indistinguishable when only using morphology. The problematic distinction among species of the complex has made study of malaria transmission and ecology of An. albitarsis s.l. difficult. Consequently, involvement of species of the An. albitarsis complex in human Plasmodium transmission is not clear throughout its distribution range. With the aim of clarifying the taxonomy of the above species, with the exception of An. albitarsis F, we present comparative morphological and morphometric analyses, morphological redescriptions of three species and description of two new species using individuals from populations in Brazil, Paraguay, Argentina and Venezuela. The study included characters from adult females, males, fourth-instar larvae, pupae and male genitalia of An. albitarsis, An. marajoara, An. deaneorum and An. oryzalimnetes n. sp. For An. janconnae n. sp. only characters of the female, male and male genitalia were analyzed. Fourth-instar larvae, pupae and male genitalia characteristics of all five species are illustrated. Bionomics and distribution data are given based on published literature records.


Subject(s)
Anopheles/anatomy & histology , Anopheles/classification , Animals , Female , Larva/anatomy & histology , Larva/classification , Latin America , Male
6.
Mem. Inst. Oswaldo Cruz ; 104(6): 823-850, Sept. 2009. ilus, graf, tab
Article in English | LILACS | ID: lil-529553

ABSTRACT

The Anopheles (Nyssorhynchus) albitarsis complex includes six species: An. albitarsis, Anopheles oryzalimnetes Wilkerson and Motoki, n. sp., Anopheles marajoara, Anopheles deaneorum, Anopheles janconnae Wilkerson and Sallum, n. sp. and An. albitarsis F. Except for An. deaneorum, species of the complex are indistinguishable when only using morphology. The problematic distinction among species of the complex has made study of malaria transmission and ecology of An. albitarsis s.l. difficult. Consequently, involvement of species of the An. albitarsis complex in human Plasmodium transmission is not clear throughout its distribution range. With the aim of clarifying the taxonomy of the above species, with the exception of An. albitarsis F, we present comparative morphological and morphometric analyses, morphological redescriptions of three species and description of two new species using individuals from populations in Brazil, Paraguay, Argentina and Venezuela. The study included characters from adult females, males, fourth-instar larvae, pupae and male genitalia of An. albitarsis, An. marajoara, An. deaneorum and An. oryzalimnetes n. sp. For An. janconnae n. sp. only characters of the female, male and male genitalia were analyzed. Fourth-instar larvae, pupae and male genitalia characteristics of all five species are illustrated. Bionomics and distribution data are given based on published literature records.


Subject(s)
Animals , Female , Male , Anopheles/anatomy & histology , Anopheles/classification , Latin America , Larva/anatomy & histology , Larva/classification
7.
São Paulo; s.n; 2007. 187 p. ilus, mapas, tab, graf.
Thesis in Portuguese | LILACS | ID: lil-494125

ABSTRACT

Introdução: Os complexos An. oswaldoi e An. albitarsis são formados por espécies morfologicamente semelhantes e, algumas delas, são importantes vetores de plasmódios que causam a malária humana. A separação das espécies de cada complexo é problemática devido ao polimorfismo e sobreposição dos caracteres morfológicos utilizados em chaves de identificação, que muitas vezes só é alcançada com o uso de marcadores moleculares. No entanto, a identificação correta das espécies se faz necessária para a avaliação adequada da importância epidemiológica das mesmas. Infelizmente, são poucos os estudos que objetivam a caracterização morfológica dos membros do complexo An. oswaldoi e An. albitarsis. Objetivos: Caracterizar morfologicamente e molecularmente o An. oswaldoi s.s.; caracterizar morfologicamente cinco espécies do complexo An. albitarsis; estabelecer caracteres morfológicos que permitam a separação entre as espécies do complexo An. albitarsis; solucionar problema de nomenclatura de An. marajoara. Métodos: Foram utilizados espécimes disponíveis nos acervos da Coleção Entomológica do Departamento de Entomologia da Faculdade de Saúde Pública (FSP/USP), do Museu Nacional do Rio de Janeiro e do Instituto Oswaldo Cruz, Rio de Janeiro, Brasil e do National Museum of Natural History (NMNH), EUA.Foram descritas e ilustradas as fêmeas adultas, genitálias masculinas, larvas de quarto estadio e pupas de seis espécies de Nyssorhynchus, e a larva de primeiro estadio de An. albitarsis s.s. Foram utilizados 40 caracteres de fêmeas adultas das cinco espécies do complexo An. albitarsis. Nas análises morfométricas foram empregadas técnicas de análises estatísticas multivariadas. Resultados: Os adultos machos e fêmeas, larvas de quarto estadio e pupas de An. oswaldoi s.s., An. albitarsis s.s.,An. marajoara e An.deaneorum foram redescritos, e descritos aqueles de An. albitarsis B e An. albitarsis E. Os resultados das análises multivariadas dos caracteres morfométricos demonstraram...


Subject(s)
Animals , Anopheles/anatomy & histology , Anopheles/classification , Culicidae/anatomy & histology , Culicidae/classification , Insect Vectors , Larva/anatomy & histology , Multivariate Analysis , Malaria/transmission , Pupa/anatomy & histology
8.
Rev. bras. entomol ; 50(4): 453-457, dez. 2006. tab
Article in English | LILACS | ID: lil-445421

ABSTRACT

During studies on the dynamics of malaria transmission in Marajó Island, State of Pará, Brazil, Galvão & Damasceno (1942) collected a single specimen of a new species that they named Anopheles (Nyssorhynchus) marajoara Galvão & Damasceno, 1942. Now, examining genitalia slide associated to the holotype, we observed that the ventral claspette of the male genitalia is distinct from those of all other species of the Argyritarsis Section and consequently from members of the complex Anopheles albitarsis Lynch Arribalzaga, 1878. The male genitalia of the slide belong to a specimen of Anopheles aquasalis Curry, 1932, nevertheless, it was originally labeled as Anopheles marajoara. To solve this problem, we are setting aside the male genitalia slide associated with the holotype of Anopheles marajoara and excluding it from the type material. Illustrations of the male genitalia and adult male are included.


Durante estudos sobre a dinâmica de transmissão da malária na Ilha de Marajó, Estado do Pará, Brasil, Galvão & Damasceno (1942) coletaram um espécime de nova espécie de anofelíneo, que foi denominada Anopheles (Nyssorhynchus) marajoara Galvão & Damasceno, 1942. Ao examinarmos a lâmina com a genitália, que acompanha o holótipo, observamos que o claspete ventral da genitália masculina difere daqueles apresentados pelas espécies da Seção Argyritarsis e, conseqüentemente, de membros do Complexo Anopheles abitarsis Lynch Arribalzaga, 1878. Consideramos que a genitália masculina que foi montada na lâmina associada ao holótipo pertence a um espécime de Anopheles aquasalis Curry, 1932, embora o adulto e as exúvias de larva e da pupa sejam de Anopheles marajoara. Com o intuito de resolver este problema , nós excluímos a lâmina com a genitália de macho do material tipo de Anopheles marajoara. A título de elucidação, foram feitas ilustrações da genitália masculina em questão, bem como do adulto de An. marajoara.


Subject(s)
Animals , Male , Anopheles , Culicidae/anatomy & histology , Culicidae/classification , Genitalia, Male , Species Specificity
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