The effects of exposure to a single sublethal dose of the pesticide malathion on the courtship and mating behavior of the lycosid, Rabidosa rabida (Walckenaer 1837) is explored. Animals were tested in combinations where one or both sexes were exposed to the insecticide. The data indicate that while there was no effect on the patterning of courtship behavior, control males initiated courtship more rapidly than dosed animals. Mating behavior was severely disrupted and resulted in most dosed males being killed by females without achieving copulation.