Disease relations: Nyssorhynchus nuneztovari is considered the principal vector of Plasmodium vivax in western Venezuela and northern Colombia (Gabaldon, 1981) and secondary vector in the Brazilian Amazon (Forattini, 2002).
Immature stages have been collected in swampy areas with margins with emerging vegetation; lagoons, small or large, with or without plants; in vehicle or animal tracks, always with freshwater and shady sites (Forattini, 2002). Females are considered exophilic and zoophilic in the Amazon region (Forattini, 2002) and endophilic in western Venezuela and northern Colombia (Elliott, 1972). In these last two countries, maximum activity has been recorded near midnight and marked anthropophilia (Forattina, 2002).