SOCIAL CLOSURE, AGGRESSIVE-BEHAVIOR, AND CUTICULAR HYDROCARBON PROFILES IN THE POLYDOMOUS ANT CATAGLYPHIS-IBERICA (HYMENOPTERA, FORMICIDAE)

Nestmate recognition was studied in the polydomous ant Cataglyphis ibe rica (Formicinae) in the laboratory. The study examined six colonies c ollected from two different populations 600 km apart in the Iberian pe ninsula (Barcelona and Murcia). Introduction of an alien worker into a n allocolonial arena always ended in death to the intruder, demonstrat ing that in this species societies are extremely closed. Dyadic encoun ters composed of individuals from different colonies in a neutral aren a confirmed the existence of high aggression between allocolonial indi viduals. We also investigated variability in the composition of the ma jor cuticular hydrocarbons between the colonies used in the behavioria l tests. There were marked quantitative differences between the profil es of ants from the two populations, suggesting that the populations a re completely segregated. Cuticular profiles within a population tende d to be more similar, but were nevertheless colony specific. The degre e of colony closure in C. iberica seemed to be independent of geograph ic distance since aggression between the colonies was always at its ma ximum, irrespective of their population origin.