Organic linings in nests of the fire ants Solenopsis electra Forel and Solenopsis nr. macdonaghi Santschi from Argentina

Abstract

Although fire ants have been extensively studied, not much has been published about the structure and<br />building material of their nests and even less on the lining of chamber walls. Nests built in unconsolidated sandy soils of Solenopsis electra and Solenopsis nr. macdonaghi, studied in La Pampa and Chubut (Argentina), respectively, show organic linings, which are reported herein for the first time. It is hypothesized that these organic linings may be of fecal origin, since there is no organic rich horizon in those soils. Apart from its significance as regards ant architecture and nest function, the presence of organic linings in ant nests is important for interpreting fossil nests, which have been often assigned to termites based on the presence of organic linings.