Behavioral evidence suggests the presence of a female-emitted sex pheromone in the water mite species, Arrenurus globator (O. F. Muller, 1776) (Acari: Hydrachnida; Arrenuridae).

Species from various animal taxa have been found to use pheromonal communication underwater. Although the use of pheromones in water mites has been previously suggested, experimental evidence for it remains sparse. We examined the behavioral responses of male and female Arrenurus globator to water in which conspecifics of the same and the opposite sex had been kept, in order to test the hypothesis that chemical communication occurs between sexes. Results suggest a putative female-produced sex pheromone that stimulates at least the initial steps of mating behavior in males. Males exhibited arrestant behavior, leg fanning and readiness posture more in female-conditioned water than in male-conditioned or control water. In contrast, females showed no response to either male-conditioned water or female-conditioned water.