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Knowledge of the fauna composition of anopheline mosquitoes, their ecological aspects and behavior, and influence of climatic variables on their population dynamics can help in understanding the transmission of Plasmodium parasites and thus develop more efficient strategies for the control of malaria. In the Central Atlantic Forest Biodiversity Corridor, southeastern Brazil, foci of introduced malaria have been reported among people returning from the Amazon region, north Brazil. Our objective was to evaluate and compare the anopheline fauna from a preserved environment and an adjacent peridomiciliary modified environment at the Central Atlantic Forest Biodiversity Corridor. We collected anopheline mosquitoes on a monthly basis from June 2004 to May 2006 from both these environments to understand the ecological aspects and their association with the occurrence of malaria. We captured 5,491 anopheline mosquitoes belonging to two subgenera and 11 species and studied the correlations between anopheline mosquito species and climatic variables. We considered Anopheles darlingi (Root) as the principal malaria vector and Anopheles albitarsis s. l. (Arribalzaga) as the secondary vector.

Lutzomyia Franca is the largest and most diverse sand fly genus in the New World and contains all the species involved in the transmission of American visceral leishmaniasis (AVL). Morphological characters were used to test the monophyly and to infer phylogenetic relationships among members of the Lutzomyia subgenus. Fifty-two morphological characters from male and female adult specimens belonging to 18 species of Lu. (Lutzomyia) were scored and analyzed. The resulting phylogeny confirms the monophyly of this subgenus and reveals four main internal clades. These four clades, however, do not support the classification of the subgenus in two series, longipalpis and cavernicola, because neither is necessarily monophyletic. Knowledge on phylogenetic relationships among these relevant vectors of AVL should be used as a tool for monitoring target taxa and a first step for establishing an early warning system for disease control.

We evaluated the ecological and epidemiological aspects of the sand fly fauna in an area of the Atlantic Forest biome with records of visceral and cutaneous leishmaniasis. Sand fly collections at three different localities at the National Monument of Pontoes Capixabas, State of Espirito Santo, Southeastern Brazil, were conducted by using two Centers of Disease Control and Prevention automatic light traps in the peridomiciliary environment and eight Centers of Disease Control and Prevention automatic light traps in the forested environment. Collections occurred during four consecutive nights within each of the months and locations: Sao Luiz (December 2009, May 2010, July 2010, and December 2010), Corrego Palmital de Baixo (September 2010 and October 2010), and Corrego Sao Bento (February 2011 and May 2011). We collected 21,138 sand flies belonging to 31 species and 14 genera. Of this total, 12,412 sand flies were captured in the peridomiciliary environment and 8,726 in the forested environment. All of the vector species, Lutzomyia longipalpis (=Lutzomyia longipalpis, sensu; Young and Duncan), Migonemyia migonei (=Lutzomyia migonei, sensu; Young and Duncan), and Nyssomyia intermedia (=Lutzomyia intermedia, sensu; Young and Duncan), occurred in significantly higher numbers in the peridomiciliary environment than compared with the forested environment. Our results highlight the importance of conservation in the forest remains of the National Monument of Pontoes Capixabas, because of higher species richness and diversity. Furthermore, they indicate the epidemiological role of Lu. longipalpis as the vector of Leishmania infantum within the study area, and the no evident role of Mg. migonei.

This study compares the distribution of anopheline mosquitoes in a malaria-endemic municipality (MAL) and a malaria-free municipality (FREE) in an area of the Atlantic Forest in Brazil. Simultaneous quarterly nightly captures were made in three locations in each municipality. One Shannon light trap (Shannon light traps were home made according to specifications published in Am. J. Trop. Med. 1939; 19: 131-140) (SLT) and five CDC light traps (a kind of automatic trap fed by batteries of 12 V and 7 amp/h, with dry ice as a source of CO2; John W. Hock Company, Gainesville, FL) (CLT) (two in the canopy and three at ground level) were operated from 6:00 p.m. to 6:00 a.m. More specimens were captured in MAL (362 in SLTs and 126 in CLTs) than in FREE (66 in SLTs and 59 in CLTs). For the SLTs, Simpson's dominance index was similar in MAL and FREE (D = 0.15 versus D = 0.203, P0.7), but Shannon's diversity index was higher for MAL = 1.969 versus H = 1.641, P0.01). For the CLTs, Simpson's dominance index was higher in MAL (D = 0.416 versus 0.2688, P0.001), and the Shannon diversity index was higher in FREE (H = 1.5222 versus H = 1.115, P0.01). In SLTs, Anopheles (Kerteszia) cruzii s.l. frequencies were higher in MAL (chi2 = 23.39; P = 0.000001). In CLTs, An. cruzii s.l. was present in all strata in MAL but only in the canopy inside the forest in FREE (17 specimens). An. cruzii s.l. represented a higher proportion of anophelines in MAL (chi2 = 31; P0.000001). The factors that differed in these two areas were anopheline species density and An. cruzii s.l. abundance and distribution.

Lutzomyia longipalpis (Diptera: Psychodidae) is the principal vector of American visceral leishmaniasis. Several studies have indicated that the Lu. longipalpis population structure is complex. It has been suggested that genetic divergence caused by genetic drift, selection, or both may affect the vectorial capacity of Lu. longipalpis. However, it remains unclear whether genetic differences among Lu. longipalpis populations are directly implicated in the transmission features of visceral leishmaniasis. We evaluated the genetic composition and the patterns of genetic differentiation among Lu. longipalpis populations collected from regions with different patterns of transmission of visceral leishmaniasis by analyzing the sequence variation in the mitochondrial cytochrome b gene. Furthermore, we investigated the temporal distribution of haplotypes and compared our results with those obtained in a previous study. Our data indicate that there are differences in the haplotype composition and that there has been significant differentiation between the analyzed populations. Our results reveal that measures used to control visceral leishmaniasis might have influenced the genetic composition of the vector population. This finding raises important questions concerning the epidemiology of visceral leishmaniasis, because these differences in the genetic structures among populations of Lu. longipalpis may have implications with respect to their efficiency as vectors for visceral leishmaniasis.