Distinct population structure for co-occurring Anopheles goeldii and Anopheles triannulatus in Amazonian Brazil

Abstract

To evaluate whether environmental heterogeneity contributes to the genetic heterogeneity in Anopheles triannulatus, larval habitat characteristics across the Brazilian states of Roraima and Pará and genetic sequences were examined. A comparison with Anopheles goeldii was utilised to determine whether high genetic diversity was unique to An. triannulatus. Student t test and analysis of variance found no differences in habitat characteristics between the species. Analysis of population structure of An. triannulatus and An. goeldii revealed distinct demographic histories in a largely overlapping geographic range. Cytochrome oxidase I sequence parsimony networks found geographic clustering for both species; however nuclear marker networks depicted An. triannulatus with a more complex history of fragmentation, secondary contact and recent divergence. Evidence of Pleistocene expansions suggests both species are more likely to be genetically structured by geographic and ecological barriers than demography. We hypothesise that niche partitioning is a driving force for diversity, particularly in An. triannulatus.

Malaria in Brazil: what happens outside the Amazonian endemic region

“…The numerous water reservoirs from recently constructed hydroelectric plants increased the number of suitable larval habitats for An. darlingi as well as for other potential Nyssorhynchus malaria vectors, such as species of the Albitarsis and Triannulatus complexes ( Gomes et al 2008 , 2013 , Limongi et al 2008 , Meneguzzi et al 2009 , Da Silva et al 2013 , McKeon et al 2013 , Ribeiro et al 2013 ). Along the coastal lowlands, introduced malaria cases and/or small epidemics have emerged on occasion and localities with brackish water and Nyssorhynchus and An.…”

Avian malaria, ecological host traits and mosquito abundance in southeastern Amazonia

“…For species determination, we used keys published by Galindo et al (1954) and Forattini (1962Forattini ( , 1965aForattini ( , b, 2002. We used the infrageneric classification scheme of the genus Anopheles from McKeon et al (2013), Moreno et al (2013) and Ruiz-Lopez et al (2013), which differentiates among groupings of cryptic but presently unnamed lineages. The abbreviation of genera and subgenera follows the guidelines suggested by Reinert ( 2001), according to the newly proposed mosquito nomenclature of the Walter Reed Biosystematics Unit, Smithsonian Institution (catalogue available at http://www.mosqui tocatalog.org/taxon_table.aspx) and Harbach (2013) in the Mosquito Taxonomic Inventory (www.mos quito-taxonomic-inventory.info/).…”

Exploring malaria vector diversity on the Amazon Frontier

“…The haplotypes included in this study come from the Amazonian states of Acre and Amapá, as well as from the states of Minas Gerais to the east, Espírito Santo on the Atlantic coast, São Paulo in the south east of Brazil, and neighbouring Colombia. Despite a considerable geographic distribution and habitat range [ 91 , 92 ], results from the current analysis show that, although the Ny. triannulatus s.l.…”

“…triannulatus are considered intraspecific. It appears that relationships may be better explained by complex population histories [ 92 ], where elevated levels of genetic diversity have been maintained perhaps by historical fragmentation, secondary contact and gene-flow followed by more recent divergence due to geographical isolation. Further phylogenetic and species delimitation analyses at multiple loci may reveal more compelling support for species designation within Ny.…”