Ocorrência de Toxorhynchites (Diptera, Culicidae) em Mata Atlântica, Viçosa, MG, e predação de T. violaceus sobre larvas de Aedes aegypti

• Autor(a) principal: Simões, Daniel Albeny
• Data de Publicação: 2008
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://locus.ufv.br/handle/123456789/2207
• topic: Aedes aegypti; Predação; Toxorhynchites violaceus; Aedes aegypti; Predation; Toxorhynchites violaceus; CNPQ::CIENCIAS BIOLOGICAS::ECOLOGIA

Toxorhynchites are long legs Culicidae. Their larvae are aquatic predators that feed on invertebrate immatures, mainly mosquito larvae, in natural or artificial water reservoirs or ponds, where larvae of mosquito disease vectors develop. Toxorhynchites adults feed exclusively on carbohydrates, what make them incapables of transmitting pathogens to human beings. Species of Toxorhynchites are potential agents for biological control of mosquitoes as Aedes aegypti, that are responsible for dengue and yellow fever diseases. The aims of the present study were: (i) survey the occurrence of Toxorhynchites species in fragments of Atlantic Forest, and (ii) evaluate the predation potential of Toxorhynchites violaceus larvae from Serra da Piedade at Caeté, Minas Gerais State. Five hundred oviposition traps were spread out in five different areas to sample the possible occurrence of Toxorhynchites species in Viçosa region. Larvae obtained from traps were then reared in laboratory until adults, which were sent for identification. Toxorhynchites theobaldi and Toxorhynchites pusillus were then identified from Viçosa, Minas Gerais. The predation potential was verified through out two experiments. First, different densities of the prey A. aegypti were offered to larvae of T. violaceus. Results has showed that the number of prey killed by the predator increased significantly (p=7,662xl0-12) with the increase of the number of offered prey. In the second experiment, the number of prey was the same, but the water column height and the surface used for prey and predator respiration varied. Data showed a clear tendency to diminish the number of preys killed as the water column height increased (p=0.001720) as well as the surface used for breathing (p=0.003035).