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

Abstract

BackgroundThe 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.MethodsLarvae, 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.ResultsBayesian 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 multi-locus COI-ITS2 barcode, however, resolved all species in a neighbor joining tree and successfully identified all species queries using the “best close match” approach.ConclusionsOur study corroborates the existence of An. albertoi, An. CP Form and An. strodei in the 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 C identified in this study.

Comparative morphological and molecular analysis confirms the presence of the West Nile virus mosquito vector, Culex univittatus, in the Iberian Peninsula

“…These results show one of the limitations of barcoding identification that is the dependence on available similar sequences for evaluation. Other authors have also reported some difficulties in distinguishing some mosquito close related species by barcoding [44, 45]. Thus, the phylogenetic analysis based on the larger region of cox 1 mtDNA performed in this survey was essential to clarify the identification of Iberian specimens.…”

DNA barcoding: complementing morphological identification of mosquito species in Singapore

“…For example, COI-based barcoding has not been promising in identifying fungi and plant species [27][28][29]. Likewise, COI barcoding has failed to distinguish certain mosquito species of Anopheles and Culex [21][22][23][24][25]. Kumar et al, [23] reported that two closely related mosquito species of the genus Ochlerotatus could not be differentiated using their COI barcode.…”

“…Previous studies have proven that COI gene is an efficient and useful barcode for the identification of metazoans, including mosquitoes [21][22][23][24][25][26]. However, COI barcode may not be universally applicable to identify all animal species.…”

The phylogenetic analysis of Dalbergia (Fabaceae: Papilionaceae) based on different DNA barcodes

“…Therefore, a multi-locus approach for species identification is necessary (Lahaye et al 2008;Bourke et al 2013;Tripathi et al 2013;Bhagwat et al 2015;Hartvig et al 2015). Though the combinations ITS + matK + psbA-trnH and ITS + rbcL + psbA-trnH were not tested in this study, combined barcodes provide certainly a good species identification for Dalbergia species.…”

“…Standardization, minimization and scalability are three important principles of DNA barcoding (Hollingsworth et al 2011). In several animal DNA barcoding studies the mitochondrial cytochrome oxidase I gene (COI) has shown high ability for species discrimination (Bourke et al 2013;Huang et al 2013). However, this approach is difficult to apply for all plants species because of the low rate of nucleotide substitution in plant mitochondrial genomes (Kress et al 2005).…”