RESUMO
Mitochondrial genome sequences are widely used as molecular markers for phylogenetic studies of mosquito species complexes, such as the Anopheles albitarsis complex. Except for a few studies that employed a limited number of nuclear or mitochondrial loci to address the genetic structure and species status of Anopheles cruzii, Anopheles bellator, and Anopheles homunculus, little is known about genetic markers that can be employed instudies focusing on Kerteszia species. The complete mitochondrial genomes of seven specimens of An. bellator,An. cruzii, An. homunculus, and Anopheles laneanus were sequenced using long-range polymerase chain reaction and Illumina sequencing. The mitochondrial genomes varied from 15,446 to 15,738 bp in length and contained 37 genes (13 protein-encoding genes, 2 rRNA genes [12S rRNA and 16S rRNA] and 22 tRNA genes), and the AT-rich control region, as all do other Anopheles mitochondrial genomes sequenced to date. Specimens from four populations of An. cruzii showed differences in codon composition...
Assuntos
Animais , Anopheles/classificação , Anopheles/crescimento & desenvolvimento , Anopheles/genética , Culicidae/crescimento & desenvolvimentoRESUMO
Malaria remains a significant public health issue in South America. Future climate change mayinfluence the distribution of the disease, which is dependent on the distribution of those Anopheles mosquitoes competent to transmit Plasmodium falciparum. Here in, 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 underclimate 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 on to 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...
Assuntos
Humanos , Malária/diagnóstico , Malária/epidemiologia , Malária/prevenção & controle , Malária/transmissãoRESUMO
Specimens of neotropical Anopheles (Nyssorhynchus) were collected and identified morphologically. We amplified three genes for phylogenetic analysisthe single copy nuclear white and CAD genes, and the COI barcode region. Since we had multiple specimens for most species we were able to test how well the single or combined genes were able to corroborate morphologically defined species by placing the species into exclusive groups. We found that single genes, including the COI barcode region, were poor at confirming species, but that the three genes combined were able to do so much better. This has implications for species identification, species delimitation, and species discovery, and we caution that single genes are not enough. Higher level groupings were partially resolved with some well-supported groupings, where as others were found to be either polyphyletic or paraphyletic. There were examples of known groups, such as the Myzorhynchella Section, which were poorly supported with single genes but were well supported with combined genes. From this we can infer that more sequence data will be needed in order to show more higher-level groupings with good support. We got unambiguously good support (0.941.0 Bayesian posterior probability) from all DNA-based analyses for a grouping of An.dunhami with An. nuneztovari and An. goeldii, and because of this and because of morphological similarities we propose that An. dunhami be included in the Nuneztovari Complex. We obtained phylogenetic corroboration for new species which had been recognised by morphological differences; these will need to be formally described and named...