Sandflies are important vectors of tegumentary and visceral leishmaniasis in different countries. This study aimed at analyzing the histomorphological characteristics of digestive and reproductive organs in Lutzomyia wellcomei (Fraiha, Shaw & Lainson) using light microscopy techniques. Thirty females from the rural area of Nísia Floresta, Rio Grande do Norte state were selected, microsectioned and analyzed with an optical microscope using conventional hematoxylin-eosin staining. Results show three well-characterized regions in the digestive tube: the stomodeum, mesentery and proctodeum. The stomodeum is lined internally with a basal and epithelial membrane; the mesentery has a peritrophic matrix formed above the stomodeum lining consisting of the simple cubic epithelium overlapping the conjunctive, also common to a capsule of gonadal lining; and the proctodeum, which structurally resembles the mesentery, but with a pyloric sphincter limiting the posterior midgut. Enveloping the digestive tube is the peritoneal membrane, of mesodermal origin. Richly-detailed internal morphological characteristics of L. wellcomei have widened knowledge of this Leishmania braziliensis (Vianna)-transmitting species, an etiologic agent of American tegumentary leishmaniasis.Características Histomorfológicas de Órgãos da Digestão de Lutzomyia wellcomei Fraiha, Shaw & Lainson (Diptera, Psychodidae)Resumo. Os flebotomíneos se destacam como importantes transmissores das leishmanioses tegumentar e visceral em diferentes países. O objetivo desse estudo foi analisar características histomorfológicas de órgãos da digestão de Lutzomyia wellcomei (Fraiha, Shaw & Lainson) por meio de técnicas de microscopia. Trinta fêmeas provenientes de área rural do município de Nísia Floresta, Rio Grande do Norte foram selecionadas, microseccionadas e analisadas por microscopia ótica. Métodos de coloração histológica por hematoxilina-eosina foram empregados nas análises. Os resultados mostram o trato digestório com as três regiões bem caracterizadas, estomodeo, mesêntero e proctodeo. O estomodeo possui uma membrana basal e uma membrana epitelial que o reveste internamente; o mesêntero possui matriz peritrófica formada acima do revestimento do estomodeo constituído de epitélio cúbico simples sobreposto ao conjuntivo comum também a uma cápsula de revestimento gonadal; e o proctodeo que se assemelha estruturalmente com o mesêntero, possuindo ainda, uma região pilórica limitando o intestino médio do posterior. Envolvendo o tubo digestório, está a membrana peritonial, de origem mesodérmica. As características morfológicas internas, observadas com riqueza de detalhes em L. wellcomei ampliam o conhecimento acerca dessa espécie, transmissora de Leishmania braziliensis (Vianna), agente etiológico de leishmaniose tegumentar americana.

Anopheles darlingi Root and Anopheles aquasalis Curry are the main vectors of malaria that occur in the State of Maranhão. Entomological surveys based on the behavior and infectivity of these vectors are important for the elaboration of disease control strategies. The objectives of this work were to study the behavioral patterns of mosquitoes, determining population and hematophagic peaks, dietary preferences, infectivity rate and characterization of breeding sites in two municipalities in the State of Maranhão: Buriticupu and São José of Ribamar. Larvae and pupae were collected in breeding sites and adult females in home environments. Mosquito behavior, their dietary preferences and Plasmodium spp infection rates were analyzed. The vegetation and physicochemical patterns in the breeding sites found are in agreement with those described for species from the Amazon region and the Brazilian Atlantic coast. Anopheles darlingi was the most prevalent mosquito in Buriticupu breeding and home environments. This species was found mainly fed on human blood and naturally infected with Plasmodium vivax Grassi & Feletti and Plasmodium falciparum Welch. Anopheles aquasalis was more frequent in breeding sites in São José de Ribamar, as well as in home environments, whose specimens were mainly fed with human and bird blood. The main peaks of mosquito occurrence in Buriticupu were between 6 pm to 9 pm and in São José de Ribamar we did not record a definite peak. In the first municipality A. darlingi showed dominance over Anopheles albitarsis Lynch Arribálzaga s.l., Anopheles oswaldoi Peryassú, Anopheles nuneztovari Gabaldón and Anopheles evansae Brèthes,, besides presenting a correlation with rainfall. In the second municipality, A. aquasalis was dominant over A. albitarsis s.l. and there was a correlation between these two species and the rainy season. We conclude that the collected data contribute to elucidate the dynamics of malaria transmission in the region and guide the control actions directed to the elimination of the disease in the country.

Sandflies are important vectors of tegumentary and visceral leishmaniasis in different countries. This study aimed at analyzing the histomorphological characteristics of digestive and reproductive organs in Lutzomyia wellcomei (Fraiha, Shaw & Lainson) using light microscopy techniques. Thirty females from the rural area of Nísia Floresta, Rio Grande do Norte state were selected, microsectioned and analyzed with an optical microscope using conventional hematoxylin-eosin staining. Results show three well-characterized regions in the digestive tube: the stomodeum, mesentery and proctodeum. The stomodeum is lined internally with a basal and epithelial membrane; the mesentery has a peritrophic matrix formed above the stomodeum lining consisting of the simple cubic epithelium overlapping the conjunctive, also common to a capsule of gonadal lining; and the proctodeum, which structurally resembles the mesentery, but with a pyloric sphincter limiting the posterior midgut. Enveloping the digestive tube is the peritoneal membrane, of mesodermal origin. Richly-detailed internal morphological characteristics of L. wellcomei have widened knowledge of this Leishmania braziliensis (Vianna)-transmitting species, an etiologic agent of American tegumentary leishmaniasis.