RESUMO
The females of Mansonia are voraciously hematophagous. The spiracular apparatus of the immature, larval, and pupal forms is adapted to perforate submerged aquatic vegetation, from whose aeriferous aerenchyma they obtain the oxygen necessary for breathing. The proliferation of aquatic plants, in some cases linked to anthropic modifications that reduce water flow and/or increase organic matter content, may therefore contribute to the spread of these mosquitoes. This study aims to assess the presence of immature individuals of Mansonia in different aquatic plants of the Madeira River basin in 10 lentic and lotic environments and correlate their population density with abiotic factors such as water pH, dissolved O2, conductivity, and temperature. The sampling lasted from February 2016 to June 2018, a 29-month period during which 31,287 specimens belonging to the genus Mansonia were captured. Of the 12 species of macrophytes inspected, Eichhornia crassipes made up 70.1% of the samples. Lentic environments accounted for 58.9% of the samples and lotic environments for 41.1%. Immature individuals were most commonly found on Eichhornia crassipes, with this plant accounting for an average of 96.2% of all individuals, with a percentage ranging between 58.2% and 77.1% in different breeding areas. Only at the Foz do Igarapé Jirau site was a different distribution observed, with the number of aquatic plants more nearly equal: 83.3% of the larvae were found in Eichhornia crassipes, 9.2% in Ceratopteris pteridoides, 3.6% in E. azurea, 2.0% in Salvinia sp., and 1.9% in Pistia sp. The greatest richness was found in Iguapé do Raul. Concerning the larval/plant relationship, although less frequent, E. azurea had a higher larval density of Mansonia spp. It is important to emphasize that this finding may indicate a possible selection for this plant. Egg deposition by Mansonia spp. was more abundant in sample areas with Eichhornia crassipes and Pistia sp. The number of specimens collected was positively correlated with temperature, pH, and conductivity. These correlations showed a marked increase in the rainy season. Therefore, we were able to establish preliminary parameters of how environmental changes influence the ecology of this important genus of mosquitoes, the species of which are critical disease vectors.
Assuntos
Araceae , Malvaceae , Animais , Brasil , Humanos , Mosquitos Vetores , RiosRESUMO
This is the first report of the presence of Aedes albopictus (Skuse) in the Tocantins State, Brazil, in urban area of the Mateiros city. Immature specimens (aquatic stages) of this vector were collected in water reservoirs, treeholes, old tires and others. The existence of Ae. albopictus in the metropolitan area poses a potential risk for the interaction of this mosquito species with the urban human population.
Assuntos
Aedes , Animais , Brasil , Cidades , DemografiaRESUMO
Pela primeira vez é registrada a presença do Aedes albopictus (Skuse) em Tocantins, em área urbana da cidade de Mateiros. As coletas foram realizadas em criadouros de formas imaturas (caixas dágua, cisternas, tanques, ocos de árvores, lixo, pneus, etc). A presença de Ae. albopictus em área urbana representa um risco potencial do inter-relacionamento dessa espécie de mosquito com a população.
This is the first report of the presence of Aedes albopictus (Skuse) in the Tocantins State, Brazil, in urban area of the Mateiros city. Immature specimens (aquatic stages) of this vector were collected in water reservoirs, treeholes, old tires and others. The existence of Ae. albopictus in the metropolitan area poses a potential risk for the interaction of this mosquito species with the urban human population.
Assuntos
Animais , Aedes , Brasil , Cidades , DemografiaRESUMO
O hábito alimentar dos culicídeos foi estudado através da técnica de precipitina. As coletas foram realizadas no km 52 da rodovia Transpantaneira (MT-060), a 65km da sede do município de Poconé (MT). Bimestralmente, de dezembro de 2002 a dezembro de 2003, foram realizadas capturas em armadilha Shannon e CDC automática à base de CO2 das 15:00h às 21:00h. Foram utilizados os seguintes anti-soros: ave, roedor, humano, cavalo, boi, capivara e sapo. Das 2.134 fêmeas capturadas, 1.946 (92,2 por cento) foram coletadas em armadilha de Shannon e 188 (8,8 por cento) em armadilha CDC. Desse total, 276 fêmeas (13,0 por cento) estavam ingurgitadas e próprias para o teste de precipitina, sendo 235 (85,1 por cento) coletadas em armadilha de Shannon e 41 (14,9 por cento) em CDC. Verificou-se que 84,2 por cento dos espécimes analisados reagiram para uma fonte alimentar e 15,8 por cento para duas fontes. As espécies Mansonia titillans (Walker), Culex nigripalpus (Theobald), Aedeomyia squamipennis (Theobald) e Psorophora albigenu (Peryassu) foram as mais freqüentes e reagiram para todos os anti-soros. Os anofelinos Anopheles albitarsis (Lynch-Arribalzaga), An. matogrossensis (Lutz & Neiva) e An. triannulatus (Neiva & Pinto), com poucos espécimes, reagiram para cinco anti-soros. As demais espécies apresentaram positividade que variou de três a seis anti-soros. As estimativas do índice alimentar (feeding index) revelaram resultados positivos para oito espécies de culicídeos, destas cinco apresentaram preferência marcante para o hospedeiro capivara.
The feeding habits of culicids were studied by means of the precipitin technique. The collections were made the Trans-Pantanal highway (MT-060- km 52), at 65 km from the main settlement of the municipality of Poconé, MT, every other month, from December 2002 to December 2003. Trapping was performed using Shannon traps and CDC automatic CO2-based traps from 3:00 p.m. to 9:00 p.m. The following antisera were utilized: bird, rodent, human, horse, cattle, capybara and toad. Of the 2,134 females captured, 1,946 (92,2 percent) were collected in Shannon traps and 188 (8,8 percent) in CDC traps. Among these totals, 276 females (13,0 percent) were engorged and suitable for the precipitin test, of which 235 (85,1 percent) were collected in Shannon traps and 41 (14,9 percent) in CDC traps. It was found that 84.2 percent of the specimens analyzed reacted to one food source and 15.8 percent to two sources. Mansonia titillans (Walker), Culex nigripalpus (Theobald), Aedeomyia squamipennis (Lynch-Arribalzaga) and Psorophora albigenu (Peryassu) were the most frequently found species, and reacted to all the antisera. On the other hand, few specimens of the anophelines, Anopheles albitarsis (Lynch-Arribalzaga), An. matogrossensis (Lutz & Neiva) and An. triannulatus (Neiva & Pinto), reacted to five antisera. The other species were positive to three up to six antisera. The estimate of the feeding index revealed positive results for eight species, of these five they presented outstanding preference for the host capybara.
