An Oviposition Pheromone Associated with the Egg Rafts of Culex tarsalis1

Abstract

The response of gravid mosquitoes, Culex tarsalis Coquillett, at 3 densities to egg rafts of their own species demonstrated an egg-associated pheromone which attracts females to oviposit. Olfactometer tests with this material showed significantly greater mosquito attraction to the oviposition pheromone than to distilled water. Gravid Culex pipiens pipiens L., and Aedes aegypti (L.), did not respond to the C. tarsalis pheromone, which fact indicates that it may be species specific. Preliminary analysis of this chemical indicates other solubility, a lipid nature, and low vapor pressure.