Foundation and architecture of leaf-cutting ant nests in the genus Atta Fabricius (Hymenoptera:Formicidae).

The present study is a systematic review of the main ecological aspects of nest foundation and the subterranean architecture of established and mature of leaf-cutting ants of the genus Atta. The foundation of nests by queens, burrowing behavior, and abiotic factors affecting the success of colonies and nest distribution of these ants are discussed. The excavation of a vertical tunnel and the first chamber made by a single mated queen begin the nest foundation. Internal network of galleries and chambers in a highly complex architecture compose a mature nest of the Atta genus. The size, number, shape and position of the chambers vary with ant species, substrate, nest age and number of workers. The size of chambers is enlarged over time to allow fungus growth. A tunnel system connects chambers and underground part of the nest to the soil surface. The section of the tunnels is, in general, elliptical or circular, allowing workers and soldiers to move during nest excavation, maintenance, and foraging activities. The present review provides a detailed description of one the most complex and specialized subterranean nests of social insects.