Trophallaxis in dehydrated leaf cutting colonies of Atta sexdens rubropilosa (Hymenoptera: Formicidae)

Abstract

Trophallaxis, the transfer of liquid among individuals by oral regurgita-tion or anal deposition, occurs in many insect groups including ants. The first indication that trophallaxis could occur in leaf cutting ants (Atta sexdens ru-bropilosa) was made by Autuori in 1942. He reported water collection by this ant species, and highlighted what in those days was an undescribed behavior for this species. In 2005, Da-Silva and Ribeiro presented preliminary results suggesting the existence of trophallaxis in A. sexdens rubropilosa. Here we report on a formal test of the hypothesis of trophallaxis in that species. Our approach was to test ant pairs in which only one individual (Group I) had access to blue-dyed water and the other individual (Group II), a nest-mate, came from a colony dehydrated by offeringdry crushed corn for fungal growth. Positive results for trophallaxis were obtained in ants from four colonies and accounted for 33% - 46% of all tests in which ants from Group I drank dyed water. These results indicate that trophallaxis occurs in this species.