Members of Anopheles cryptic species complexes may exhibit behavioral differences among them, the susceptibility to malaria infection, and resistance to insecticides, thus, the specific identification has epidemiological relevance, which is not always possible by morphological criteria. Alternative methods have been employed such as those that analyze highly conserved regions of
ribosomal DNA, which varies among species, known as internal transcribed spacer (ITS). Anopheles albitarsis complex is currently composed of six species: An. albitarsis s.s., An. oryzalimnetes, An. albitarsis F, An. marajoara, An. deaneorum and An. janconnae. At least the last three are incriminated as malaria parasite vectors in the Brazilian Amazon. The aim of this study was to perform molecular identification of An. albitarsis complex species, for analysis of
ITS2 rDNA sequences, in order to assess their importance in malaria transmission in the cities of Macapá, Amapa and Peixe-Boi, Para, including
investigating the first time the occurrence of An. Albitarsis F in two epidemiologically distinct areas: the first with a history of high risk of malaria transmission and the second not (Peixe-Boi). All-night human landing catches of mosquitoes were carried out in the peridomestic environment, from January 2009 and April 2010. The females collected were morphologically identified and only An. albitarsis s.l. was dissected: head and thorax were separated for analysis of natural infection by ELISA; ovaries for parity analysis and the
carcass, legs and wings for molecular identification. In Macapá were collected 584 mosquitoes: 366 An. albitarsis s.l. (62.7%), 167 An. darlingi (28.6%), 33 An.
triannulatus s.l. (5.6%), 15 An. braziliensis (2.6%) and 3 An. nuneztovari (0.5%). It was possible to visualize the specific band An. marajoara in 320 specimens of
An. albitarsis s.l. tested. Of the remainder, 33 were negative and 13 amplified a fragment of ~ 490pb, not allowing to reach the specific diagnosis. The An.
marajoara specimens showed biological and behavioral characteristics that confirm their epidemiological importance in malaria transmission in Macapa, such as being the most prevalent species, with a higher proportion of parous females (73.0%), and therefore with the greatest chances of infected with
Plasmodium, occur in both seasons (dry and wet), presenting biting activity in all hours worked, moreover, was found infected by P.vivax and P. falciparum (natural infection rate of 3.1%). In Peixe-Boi, were captured 43 anophelines: An. triannulatus s.l. (20 specimens, 46.5%), An. albitarsis s.l. (13, 30.2%) An.
darlingi (8, 18.6%), and An. nuneztovari (2, 4.7%). All An. albitarsis s.l. collected were identified by ITS2 as An. oryzalimnetes. None was found infected by
Plasmodium, and the vast majority was parous females (84.6%). Systematic entomological surveys are needed to analyse the importance of An. oryzalimnetes in malaria transmission in the city. The An. albitarsis F was not found in the two areas studied. Our results contribute to our understanding of the epidemiology of malaria in the Brazilian Amazon region.
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