A multi-locus approach to barcoding in the Anopheles strodei subgroup (Diptera: Culicidae)

• Grant number: 13/07121-8
• Support Opportunities: Regular Research Grants - Publications - Scientific article
• Start date: June 01, 2013
• End date: November 30, 2013
• Field of knowledge: Biological Sciences - Parasitology - Entomology and Malacology of Parasites and Vectors
• Principal Investigator: Maria Anice Mureb Sallum
• Grantee: Maria Anice Mureb Sallum
• Host Institution: Faculdade de Saúde Pública (FSP). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

The ability to successfully identify and incriminate pathogen vectors is fundamental to effective pathogen control and management. This task is confounded by the existence of cryptic species complexes. Molecular markers can offer a highly effective means of species identification in such complexes and are routinely employed in the study of medical entomology. Here we evaluate a multi-locus system for the identification of potential malaria vectors in the Anopheles strodei subgroup. Larvae, pupae and adult mosquitoes (n=61) from the An. strodei subgroup were collected from 21 localities in nine Brazilian states and sequenced for the COI, ITS2 and white gene. A Bayesian phylogenetic approach was used to describe the relationships in the Strodei Subgroup and the utility of COI and ITS2 barcodes was assessed using the neighbor joining tree and "best close match" approaches. Bayesian phylogenetic analysis of the COI, ITS2 and white gene found support for seven clades in the An. strodei subgroup. The COI and ITS2 barcodes were individually unsuccessful at resolving and identifying some species in the Subgroup. The COI barcode failed to resolve An. albertoi and An. strodei but successfully identified approximately 92% of all species queries, while the ITS2 barcode failed to resolve An. arthuri and successfully identified approximately 60% of all species queries. A multilocusCOI-ITS2 barcode, however, resolved all species in a neighbor joining tree and successfully identified all species queries using the "best close match" approach. Our study corroborates the existence of An. albertoi, An. CP Form and An. strodei inthe An. strodei subgroup and identifies four species under An. arthuri informally named A-D herein. The use of a multi-locus barcode is proposed for species identification, which has potentially important utility for vector incrimination. Individuals previously found naturally infected with Plasmodium vivax in the southern Amazon basin and reported as An. strodei are likely to have been from An. arthuri Cidentified in this study. (AU)