Genetical and morphological colony structure of the Australian swarm-founding polistine wasp, Ropalidia romandi (Hymenoptera, Vespidae)

Genetical colony structure of an Australian swarm-founding polistine wasp, Ropalidia romandi, was analyzed. Inseminated females with developed ovaries (egg-layers) tended to have larger body size (measured at the median cell of the forewing) than non egg-layers. Two way ANOVA revealed that the diffe rence in body size was related to both the caste and the colony of origin. The genetic relatedness among egg-layers as detected by electrophoresis was 0.336 +/- 0.114 (mean +/- se), and that among non egg-layers was 0.161 +/- 0.035. The inbreeding coefficient among non egg-layers was found to be sig nificantly greater than zero, but this did not seem to play a major part in the increase in relatedness among progeny. The number of effective queens (mothers of new queens) was estimated to be 2.84 per colony. This number is much smaller than the actual counts of queens. This discrepancy is discuss ed in terms of possibilities that wasps practice cyclical oligogyny, matril ine localization within a colony, and genotypic behavioral specialization.