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OBJETIVO: Descrever a composição, características ecológicas e comportamentais e infectividade das espécies de anofelinos em reservas indígenas da região Amazônica. MÉTODOS: O estudo foi conduzido no ano de 2002 em aldeias das reservas indígenas Nhamundá-Mapuera e Cuminapanema no estado do Pará. Foram realizadas três coletas de duas semanas em cada reserva, com capturas de adultos e de imaturos. Anofelinos adultos foram capturados com capturador de Castro por atração humana nos ambientes intra e peridomiciliares, no período das 18h às 21h e das 18 às 06h e avaliados para verificação da paridade e infectividade para plasmódios por dissecção e ELISA. As coleções hídricas próximas às aldeias foram pesquisadas utilizando conchas de 500 ml, sendo 20 conchadas a cada 10 m, cobrindo-se a extensão máxima de 200 m de perímetro do criadouro. RESULTADOS: Foram capturadas 8.668 fêmeas somando-se as coletas das duas reservas. Anopheles darlingi foi a espécie predominante, com maior freqüência no peridomicílio. Na reserva Mapuera, a atividade hematofágica concentrou-se entre as 20h e 24h e, em Cuminapanema, manteve-se elevada até as 24h, diminuindo após esse horário e voltando a elevar-se no início da manhã. Das 6.350 fêmeas de An. darlingi examinadas, 18 estavam infectadas por Plasmodium vivax VK 247, VK 210, P. falciparum e P. malariae. Outras 1.450 fêmeas de outras espécies foram examinadas, mas nenhuma foi encontrada infectada. An. nuneztovari e Chagasia bonnae foram as espécies mais freqüentes nos criadouros das aldeias Mapuera e Cuminapanema, respectivamente. Imaturos de An. darlingi não foram localizados em Mapuera e foram capturados em apenas uma das coletas da reserva Cuminapanema. CONCLUSÕES: As populações de An. darlingi das duas reservas apresentaram comportamento exofílico e intensa atividade noturna. A ocorrência de imaturos foi pouco freqüente e a densidade larvária foi baixa. As características comportamentais dos vetores não se mostraram favoráveis às atividades usuais de controle vetorial. OBJECTIVE: To describe the composition, ecological and behavioral characteristics and infectivity of Anopheles species in indigenous reserves of the Amazon region. METHODS: The study was performed in villages of the Nhamundá-Mapuera and Cuminapanema indigenous reserves, in the state of Pará, Northern Brazil, in 2002. A total of three two-week collections were conducted in each reserve, with the capture of adult and immature forms. Adult Anopheles specimens were captured using a Castro sucking tube with human landing trap in indoor and outdoor environments, from 6.00 pm to 9.00 pm and from 6.00 pm to 6.00 am, and subsequently assessed to verify parity and infectivity by plasmodiums using dissection and ELISA. Water collections near the villages were surveyed using 500 ml ladles, with 20 ladlefuls for each 10 m, covering the maximum extent of 200 m of perimeter around the breeding spot. RESULTS: Adding up the collections from both reserves, a total of 8,668 females were captured. Anopheles darlingi was the most frequent species, with higher frequency around the homes. In the Mapuera reserve, blood feeding activity was concentrated between 8.00 pm and 12.00 am, while, in Cuminapanema, it remained high until 12.00 am, decreasing after this time and increasing again early in the morning. Of all the 6,350 An. darlingi females analyzed, 18 were infected with Plasmodium vivax VK247, VK210, P. falciparum and P. malariae. In addition, other 1,450 females of other species were analyzed, but none was found infected. An. nuneztovari and Chagasia bonnae were the most frequent species in the breeding spots of the Mapuera and Cuminapanema villages, respectively. Immature An. darlingi forms were not located in Mapuera and were captured in only one of the collections of the Cuminapanema reserve. CONCLUSIONS: An. darlingi populations in the two reserves showed exophilic behavior and intense nocturnal activity. The occurrence of immature forms was little frequent and larval density was low. Vector behavioral characteristics were not favorable for the usual vector control activities. OBJETIVO: Describir la composición, características ecológicas y de comportamiento e infectividad de las especies de anofelinos en reservas indígenas en la región Amazónica. MÉTODOS: El estudio fue conducido en el año de 2002 en aldeas de las reservas indígenas Nhamundá-Mapuera y Cuminapanema en el estado Pará (Norte de Brasil). Fueron realizadas tres colectas de dos semanas en cada reserva, con capturas de adultos e inmaduros. Anofelinos adultos fueron capturados con capturador de Castro por atracción humano en los ambientes intra y peridomiciliares, en el período de las 18 h a 21 h y de las 18 h a 6 h y evaluados para verificación de la paridad e infectividad para plasmodios por disección y ELISA. Las colecciones hídricas próximas a las aldeas fueron evaluadas utilizando cucharones de 500 mL, siendo 20 cucharones a cada 10 m, cubriéndose la extensión máxima de 200 m de perímetro del criadero. RESULTADOS: Fueron capturadas 8.668 hembras sumándose las colectas de las dos reservas. Anopheles darlingi fue la especie predominante, con mayor frecuencia en el peridomicilio. En la reserva Mapuera, la actividad hematofágica se concentró entre las 20 h y 24 h y en Cuminapanema, se mantuvo elevada hasta las 24 h, disminuyendo posterior a ese horario y volviendo a elevarse en el inicio de la mañana. De las 6.350 hembras de An. darlingi examinadas, 18 estaban infectadas por Plasmodium vivax VK 247, VK 210, P. falciparum y P. malariae. Otras 1.450 hembras de otras especies fueron examinadas, pero ninguna fue encontrada infectada. An. nuneztovari y Chagasia bonnae fueron las especies más frecuentes en los criaderos de las aldeas Mapuera y Cuminapanema, respectivamente. Inmaduros de An. darlingi no fueron localizados en Mapuera y fueron capturados en sólo una de las colectas de la reserva Cuminapanema. CONCLUSIONES: Las poblaciones de An. darlingi de las dos reservas presentaron comportamiento exofílico e intensa actividad nocturna. La ocurrencia de inmaduros fue poco frecuente y la densidad larvaria fue baja. Las características de comportamiento de los vectores no se mostraron favorables a las actividades usuales de control vectorial.

To describe the composition, ecological and behavioral characteristics and infectivity of Anopheles species in indigenous reserves of the Amazon region.The study was performed in villages of the Nhamundá-Mapuera and Cuminapanema indigenous reserves, in the state of Pará, Northern Brazil, in 2002. A total of three two-week collections were conducted in each reserve, with the capture of adult and immature forms. Adult Anopheles specimens were captured using a Castro sucking tube with human landing trap in indoor and outdoor environments, from 6.00 pm to 9.00 pm and from 6.00 pm to 6.00 am, and subsequently assessed to verify parity and infectivity by plasmodiums using dissection and ELISA. Water collections near the villages were surveyed using 500 ml ladles, with 20 ladlefuls for each 10 m, covering the maximum extent of 200 m of perimeter around the breeding spot.Adding up the collections from both reserves, a total of 8,668 females were captured. Anopheles darlingi was the most frequent species, with higher frequency around the homes. In the Mapuera reserve, blood feeding activity was concentrated between 8.00 pm and 12.00 am, while, in Cuminapanema, it remained high until 12.00 am, decreasing after this time and increasing again early in the morning. Of all the 6,350 An. darlingi females analyzed, 18 were infected with Plasmodium vivax VK247, VK210, P. falciparum and P. malariae. In addition, other 1,450 females of other species were analyzed, but none was found infected. An. nuneztovari and Chagasia bonnae were the most frequent species in the breeding spots of the Mapuera and Cuminapanema villages, respectively. Immature An. darlingi forms were not located in Mapuera and were captured in only one of the collections of the Cuminapanema reserve.An. darlingi populations in the two reserves showed exophilic behavior and intense nocturnal activity. The occurrence of immature forms was little frequent and larval density was low. Vector behavioral characteristics were not favorable for the usual vector control activities.