The Functioning of Species Specific Olfactory Pheromones in the Biology of a Mosquito Eating Jumping Spider from East Africa
Having unique, complex eyes and vision based on exceptional spatial acuity, salticid spiders are known for their vision based predatory and mating strategies. Yet Evarcha culicivora, the salticid we consider here, is known for predatory and mating strategies based strongly on the interplay of vision and olfaction. This unusual East African species feeds indirectly on vertebrate blood by choosing blood carrying female mosquitoes as preferred prey, which it can identify by sight and by smell. Moreover, E. culicivora's mating strategy is unusual because, unlike the prevailing general pattern among spiders, where males are more active in courtship and females are more active in mate choice, both roles are characteristic of both sexes of E. culicivora. There is also an unusual relationship between diet and mating in this species, with blood meals making both sexes more attractive as potential mates. However, findings from the present study demonstrate that, regardless of source spider diet and even when restricted to using chemoreception in the absence of seeing another spider, both sexes can discriminate between opposite sex conspecifics and opposite sex heterospecifics. Yet there is no evidence that diet (blood versus no blood) influences the attractiveness of opposite sex heterospecific individuals to E. culicivora. Evidence that the odor of opposite sex conspecifics is salient to E. culicivora comes from three different experimental designs (retention testing, choice testing and courtship initiation testing) The effective odor source can be either the presence of the spider or the presence of the spider's draglines alone.
Journal of Insect Behavior