This article concerns the socio-anthropology of an ordinary insect, the mosquito. The recent changes in the relationship between man and animals have been highlighted by a recent local controversy in the Camargue concerning mosquito eradication. A first step gives a dualist shape to this controversy, opposing anthropocentrism and biocentrism. Subsequently, such a dual order is questioned by the permeability of the old frontiers which exist between nature and culture, useful and harmful, scientific and popular knowledge, protection and predation. Finally, the insect has not only a social, political and economic impact, but becomes a pretext speaking not only of the relationship between man and nature, but also of humans themselves and their relationship to their own species.