Abstract

Adult reproductive behaviour in Asolcus basalis, a solitary parasite of the egg masses of Nezara viridula smaragdula, presents various remarkable features. These include: male aggressive behaviour, in which one male takes possession of an egg mass and drives away all other males; high male mating capacity, which permits the possessing male to fertilize virtually all females emerging from the egg mass it possesses; marking of the host by the female after parasitizing it, this being the basis for a considerable ability on the part of females to discriminate between parasitized and unparasitized hosts; and female aggressive behaviour in which one female drives all other females from an egg mass as soon as it is more or less completely parasitized. It is thought that the value to the species of these and other features of adult behaviour is that they increase the total female searching capacity for hosts. It is suggested that similar forms of reproductive behaviour may be widespread in some groups of the Scelionidae.