Colony Structure and Nest Location of Two Species of Dacetine Ants:Pyramica ohioensis(Kennedy & Schramm) andPyramica rostrata(Emery) in Maryland (Hymenoptera: Formicidae)

Abstract

The discovery of numerousPyramica ohioensisandP. rostratacolonies living in acorns, as well as the efficient recovery of colonies from artificial nests placed in suitable habitats, opens a new stage in the study of North American dacetine ants. Here we present detailed information, based on 42 nest collections, on the colony structure of these two species.P. ohioensiscolonies are smaller than those ofP. rostrata. Both species are polygynous, but nests ofP. ohioensiscontain fewer dealate queens than those ofP. rostrata. This is the first report of multiple collections ofPyramicacolonies nesting in fallen acorns, and of the use of artificial nesting cavities to sample for dacetines in the soil and leaf litter. We describe an artificial cavity nest design that may prove useful in future investigations.