Molecular taxonomy and evolutionary relationships in the Oswaldoi-Konderi complex (Anophelinae: Anopheles: Nyssorhynchus) from the Brazilian Amazon region.

José Ferreira Saraiva,Raimundo Nonato Picanço Souto,Vera Margarete Scarpassa,Michael Knapp

doi:10.1371/journal.pone.0193591

José Ferreira Saraiva, Raimundo Nonato Picanço Souto + Show 2 more

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https://doi.org/10.1371/journal.pone.0193591

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Abstract

Recent studies have shown that Anopheles oswaldoi sensu lato comprises a cryptic species complex in South America. Anopheles konderi, which was previously raised to synonymy with An. oswaldoi, has also been suggested to form a species complex. An. oswaldoi has been incriminated as a malaria vector in some areas of the Brazilian Amazon, Colombia, Peru and Venezuela, but was not recognized as a vector in the remaining regions in its geographic distribution. The role of An. konderi as a malaria vector is unknown or has been misattributed to An. oswaldoi. The focus of this study was molecular identification to infer the evolutionary relationships and preliminarily delimit the geographic distribution of the members of these complexes in the Brazilian Amazon region. The specimens were sampled from 18 localities belonging to five states in the Brazilian Amazon and sequenced for two molecular markers: the DNA barcode region (COI gene of mitochondrial DNA) and Internal Transcribed Spacer 2 (ITS2 ribosomal DNA). COI (83 sequences) and ITS2 (27 sequences) datasets generated 43 and 10 haplotypes, respectively. Haplotype networks and phylogenetic analyses generated with the barcode region (COI gene) recovered five groups corresponding to An. oswaldoi s.s., An. oswaldoi B, An. oswaldoi A, An. konderi and An. sp. nr. konderi; all pairwise genetic distances were greater than 3%. The group represented by An. oswaldoi A exhibited three strongly supported lineages. The molecular dating indicated that the diversification process in these complexes started approximately 2.8 Mya, in the Pliocene. These findings confirm five very closely related species and present new records for these species in the Brazilian Amazon region. The paraphyly observed for the An. oswaldoi complex suggests that An. oswaldoi and An. konderi complexes may comprise a unique species complex named Oswaldoi-Konderi. Anopheles oswaldoi B may be a potential malaria vector in the extreme north of the Brazilian Amazon, whereas evidence of sympatry for the remaining species in other parts of the Brazilian Amazon (Acre, Amazonas, Pará and Rondônia) precluded identification of probable vectors in those areas.

Highlights

Neotropical region is among the most diverse in the world, in north South America
In Neotropical region, morphological analysis along with the use of multiple molecular markers have contributed to the recognition of new cryptic species complexes in anophelines, especially in the Nyssorhynchus subgenus, such as An. albitarsis [5], An. benarrochi [6,7], An. nuneztovari [4,8,9,10], An. triannulatus [11,12], An. oswaldoi [13,14,15,16], An. konderi [7,14,16], and the An. strodei subgroup [17], and in the Kertezia subgenus, such as An. cruzii [18,19]
From the total anophelines collected in this study, 95 specimens were morphologically identified as An. oswaldoi s.l./An. konderi s.l. These specimens were collected at 18 sites in the Brazilian Amazon region

Summary

Introduction

Neotropical region is among the most diverse in the world, in north South America. It has been a target of research focused on elucidating the origin of biological diversity and speciation models [1]. This biodiversity extends to Anophelinae mosquitoes [2]. In the most species studied, the findings suggest that the diversification process started in the Pliocene and Pleistocene epochs [3,4]. A study demonstrated that Brazilian populations of the main malaria vector, An. darlingi, may comprise a species complex [20]

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