An exterminator for insects, for example mosquitoes, including: a) a container open on an upper side and filled with a water-containing fluid, including an inner wall with a smooth surface descending steeply towards the fluid, b) a cover at a distance above the open upper side of the container, and c) a float in the container, under the cover, and which can move up and down with the fluid level. The float includes a float body which extends above the surface of the fluid and which includes a structure which remains dry in a form of a gauze, net, cloth, screen, grid or fabric, on to which an electrostatic coating layer in a form of a platinum complex-containing silicone composition is provided.