Objective To investigate the role of visual and olfactory cues in sex recognition in the sexually dimorphic butterfly Cethosia cyane cyane, and to further understand the sexual interactions.

Method The females were placed in an insectary with three kinds of models, i.e. dissected natural wings (♀ and ♂), printed paper wings attached (♀ and ♂), and live adults (♀ and ♂), respectively. The frequency of female visiting the models was recorded.

Result When only visual or olfactory cues existed, the frequency of female visiting the male models was higher than that of the female models. There were significant differences in the average frequency of females visiting females and males when both winged models and paper models presented, indicating that the females could distinguish the gender of conspecifics using visual cues alone. And there were significant differences in the average frequency of females visiting female and male odor models, indicating that the females could use olfactory cues to distinguish the sexes. When both visual and olfactory cues existed, there were significant differences among the average frequency of females visiting normal males, male winged models and male odor models, suggesting that the females were more likely to prefer the composite, multimodal display.

Conclusion Female C. cyane cyane use both visual and olfactory cues to distinguish the gender of conspecifics during courtship. The females are more likely to prefer the composite, multimodal display.