Ocorrência e biologia do Rhodnius neglectus Lent, 1954 em macaubeiras da periferia de Belo Horizonte, Minas Gerais

Abstract

Eighty-one "macaubeiras" palm-trees (Acrocomia sclerocarpa) from the periphery of Belo Horizonte city were cut down and dissected between April 1979 and July 1980. 60.5% of the trees were positive for R. neglectus and 463 specimens of this insect were collected, providing a mean rate of 9,45 individuals for positive palm-trees. R. neglectus seems to present a single annual generation in this region, but evidence was obtained that two generations may occur. Its spawn period is related to the hot months of the year, when younger insects prevail over the adults. This observation suggests that higher population densities are related to better feeding conditions and to minor densities of specific predators such as Telenomus sp., ants, spiders, hemipters, scorpions and pseudo scorpionidae. The Trypanosoma cruzi infection index was 15,9%, suggesting that R. neglectus is a very important vector of silvatic infections in the region. Marsupials are the main vertebrate source of T. cruzi infection. R. neglectus is strongly associated with palm-trees in the area, and with the various species of birds that haunt them. So far, there is no evidence suggesting R. neglectus to be an important vector of human Chagas' disease in the region.

Ecological aspects of Rhodnius nasutus Stål, 1859 (Hemiptera: Reduviidae: Triatominae) in palms of the Chapada do Araripe in Ceará, Brazil

“…Diotaiuti and Dias (1984) studied another species of macaúba palm (formerly Acrocomia sclerocarpa, now Acrocomia. aculeata) in the periphery of Belo Horizonte, Minas Gerais, and found an infestation rate of 60.5% for R. neglectus, and that some palms were also being inhabited by Panstrongylus megistus.…”

“…Some triatomine species are associated with only a few bloodmeal sources, while others are highly promiscuous. Diotaiuti and Dias (1984) analysed bloodmeals of R. neglectus captured in macaúba palms near Belo Horizonte and found blood from a wide variety of hosts, including cold-blooded animals, birds and mammals (including man). However, bird blood was most prevalent in meals of R. neglectus.…”

Estrutura de populações de Rhodnius neglectus Lent e Psammolestes tertius Lent & Jurberg (Hemiptera, Reduviidae) em ninhos de pássaros (Furnariidae) presentes na palmeira Mauritia flexuosa no Distrito Federal, Brasil

“…Resultados com populações de R. neglectus em palmeiras do gênero Acrocomia também mostram que há um crescimento das colô-nias no verão (estação chuvosa), porém apontam a presença de ovos em menor quantidade no inverno seco (DIOTAIUTI & DIAS 1984). No presente trabalho, a abundância de R. neglectus foi maior na seca (62% dos indivíduos coletados) e fêmeas reprodutivas foram observadas em ambas as estações, indicando mais de um evento reprodutivo por ano.…”

“…1). Aspectos bionô-micos dessas espécies como ciclo biológico, longevidade e estrutura etária são conhecidos em condições de laboratório (PERLOWAGORA-SZUMLEWICZ 1976, MELLO 1977a,b, FORATTINI et al 1979, HEITZMANN-FONTENELLE 1984, SILVA & LUSTOSA 1993, CANALE et al 1999, ROCHA et al 2001, sendo poucos os estudos em ecótopos silvestres (DIOTAIUTI & DIAS 1984, GURGEL-GONÇALVES et al 2004. O objetivo deste estudo é analisar a infestação e estrutura etária de populações de R. neglectus e P. tertius em ninhos de pássaros (P. ruber) presentes na palmeira M. flexuosa, em quatro áreas e duas estações climáticas do Distrito Federal (seca e chuvosa).…”

Triatoma sordida Stål 1859 (Hemiptera, Reduviidae: Triatominae) in palms of northeastern Argentina

“…In Brazil, the synonyms species A. sclerocarpa was mostly infested by R. neglectus and secondarily by T. sordida and P. megistus (Barretto et al 1969, Diotaiuti & Dias 1984.…”