Reproductive dominance controlled by mutilation in the queenless ant Diacamma australe

Abstract

the latter will be aroused and will mount the female laterally. Stage 3: subsequently, the male settles on the female's dorsum in a parallel position for a period of 0.5 - 1.0 min, while the female (with the male on her dorsum) will commence walking. Stage 4: the male turns his body by ~ 180 ~ and transfers his gnathosoma and part of his idiosoma beyond the margin of the female's opisthosoma. The male will then attach himself to the latter by his anal and tarsal suckers. In this position both sexes remain linked for 128- 219 min, during which the aedeagus is in- serted to the bursa copulatrix. Copu- latory movements are usually per- formed for an average period of 30 min. Insemination involves the produc- tion and transfer of spermatophores to the receptaculum seminis of the female; this process has been described in detail [4,5]. The events of stage 1 suggest the in- volvement of a male-produced pher- omone causing the recognition of males by the females, while the events of stages 2 and 3 indicate the utilization of a female-produced pheromone which elicits mating activity in the males. The use of sex pheromones for mate finding appears particularly important for A. siro, as this species lacks the capability of visual perception. The above results were corroborated by the observed attractiveness of an ex- tract of male A. siro for conspecific females as well as the sexual stimula- tion of male flour mites by an extract of female A. siro. Figure la reveals that