Effect of using forced and free oviposition methods to obtain eggs and larvae of Mansonia (Diptera: Culicidae) females from Rondonia, Brazil (western Amazon)

ABSTRACT

ABSTRACT Species of the genus Mansonia Blanchard are disease pathogen vectors in some regions of the world and can cause considerable inconvenience due to their bites when present in high numbers. However, little is known regarding their biology in Brazil. The objective of this work was to investigate some reproductive parameters of Mansonia from the western Brazilian Amazon. Females were captured in the field using human landing catches in rural areas of Porto Velho, Rondonia, Brazil. The mosquitoes were identified and separated into two groups for oviposition forced, i.e., with wing removal, and free oviposition, without wing removal. Daily observations of oviposition and female survival were conducted until oviposition. The eggs and subsequent larvae were counted for fecundity and fertility evaluation, respectively. The species collected in this study were Mansonia amazonensis (Theobald), Mansonia humeralis Dyar & Knab and Mansonia titillans (Walker). The oviposition percentage for Ma. amazonensis was much lower than for Ma. humeralis and Ma. titillans. Forced oviposition resulted in a higher number of ovipositing females only for Ma. humeralis. Fecundity and fertility were not affected by the oviposition method. Egg and larval numbers were generally lower for Ma. amazonensis compared with the other species. Forced oviposition may be a tool to increase the number of ovipositing females depending on the Mansonia species studied in order to establish colonies in the laboratory.