Dinâmica populacional e parasitismo de Himenópteros parasitóides de Chrysomya megacephala (Fabricius) (Diptera, Calliphoridae), no Rio de Janeiro, RJ

Abstract

ABSTRACT. Population dynamics and parasitism of hymenopterans parasitoids of Chrysomya megacephala (Fabricius) (Diptera, Calliphoridae), in Rio de Janeiro city, Brazil. This study was carried out from August 1999 to July 2000 to evaluate the population dynamics and to know the parasitoids of Chrysomya megacephala (Fabricius, 1794) at the Instituto Oswaldo Cruz (IOC/ FIOCRUZ) and Jardim Zoológico, in Rio de Janeiro City. Samplings were conducted weekly with third instar larvae of the fly and putrefying ground beef. It was identified three species of hymenopterans parasitoids: Tachinaephagus zealandicus Ashmead, 1904 (Encyrtidae), Pachycrepoideus vindemiae (Rondani, 1875) (Pteromalidae) and Nasonia vitripennis (Walker, 1836) (Pteromalidae). In both sampling areas, T. zealandicus was the species with the highest parasitism rate of C. megacephala, followed by P. vindemiae and N. vitripennis. Parasitoid population decreases drastically in the summer (average temperature = 28°C; precipitation = 6.5 mm). The population peak of parasitoids was verified at the end of autunm and during the whole winter. At Jardim Zoológico, supply of garbage was a strong influence in the population dynamics of himenopteran parasitoids identified in this study, and the population peak in this area was verified in June and July 2000.

Pachysomoidessp. (Hymenoptera: Ichneumonidae: Cryptinae) ParasitizingPolistes versicolor(Hymenoptera: Vespidae) in Viçosa, Minas Gerais State, Brazil

“…parasitism of a P. versicolor colony that contains pupae, larvae and eggs is consistent with other studies that show the parasitoids C. pegasalis, P. fulvus and X. peckii prefer to oviposit in colonies of P. metricus with immature individuals (Hodges et al, 2003). Furthremore, the temperatures between 15.7uC and 25.7uC appear optimal for social wasp colonies to be parasitized, because this may Bouček, 1992;de Santis, 1980 increase the effectiveness of natural enemies (de Carvalho et al, 2005). The Pachysomoides sp.…”

Registro de Aphaereta laeviuscula (Spinola) (Hymenoptera: Braconidae) e Nasonia vitripennis (Walker) (Hymenoptera: Pteromalidae) como parasitóide de Cochliomyia hominivorax (Coquerel) (Diptera: Calliphoridae), no estado do Rio de Janeiro

“…Carvalho et al (2003Carvalho et al ( , 2005 relataram a espécie N. vitripennis como parasitóide de Chrysomya megacephala (Fabricius) dentre as três espécies determinadas como seus inimigos naturais. Este trabalho confirma a pesquisa, pois utilizaram-se metodologias semelhantes para a coleta dos parasitóides.…”

“…Carvalho et al (2005) encontraram N. vitripennis na proporção de 11,8% e 22,6%, na Fundação Oswaldo Cruz (Fiocruz) e no Jardim Zoológico do Rio de Janeiro, respectivamente, ambas classificadas como espécies acidentais. Os resultados encontrados no presente trabalho contradizem tais resultados, quando analisados na área urbana (58,33%), onde a espécie foi categorizada como constante.…”

Exposure of a single host (Chrysomya megacephala) (Calliphoridae) to different quantities of female parasitoids (Nasonia vitripennis) (Pteromalidae)

“…Calliphorids constitute a real problem in rural and urban environments where places with inadequate water and sewage infra-structure and buildup of decomposing organic material become nurseries for these insects and raise the probability of pathogen transmission and disease propagation (Furlanetto et al 1984;Carvalho et al 2005). Besides its role in disease propagation, calliphorids also act as vectors for Dermatobia hominis (Linnaeus Jr., 1781) (Marinho et al 2003), and cause facultative or obligatory myiasis in humans and animals (Guimarães et al 1983, Guimarães & Papavero 1999.…”