Worker laying in the absence of an ergatoid queen in the ponerine ant genus Plectroctena

Abstract

Ergatoid queens (without wings and worker-like) occur in Plectroctena mandibularis and P. conjugata. Five nests of these species were incompletely excavated, and an ergatoid was collected in only one of them. The orphaned groups of workers were kept in the laboratory for several months, during which time many eggs were laid. Some of these developed into males. Thus workers can lay haploid eggs in the absence of an ergatoid queen. This was confirmed by dissecting 60 workers from various nests: many of them had mature oocytes in their ovaries, and inseminated individuals were not found. Various data on foraging behaviour and male activity are also presented.