REPRODUCTION BY VIRGIN QUEEN FIRE ANTS IN QUEENLESS COLONIES - COMPARATIVE-STUDY OF 3 TAXA (SOLENOPSIS-RICHTERI, HYBRID SOLENOPSIS-INVICTA RICHTERI, S-GEMINATA) (HYMENOPTERA, FORMICIDAE)

In the fire ant, Solenopsis invicta, some winged virgin queens are known to shed their wings (dealate) upon removal of the mated mother queen. These virgin queens then develop their ovaries and begin to lay eggs, thereby foregoing the option of leaving on mating flights and attempting to found their own colonies. Such a response of virgin queens to queenlessness has not been reported for other ants. In order to determine if virgin queens of some other fire ants (subgenus Solenopsis) would respond in the same way, experiments were conducted on S. richteri, hybrid S. invicta/richteri and S. geminata, a member of a species complex different from that of the other taxa. Just as in S. invicta, virgin queens of S. richteri and the hybrid dealated and began to lay eggs within days of the removal of the queen. In addition, workers executed many of the reproductively active virgin queens, a phenomenon also found in S. invicta. In contrast, virgin queens of S. geminata did not dealate or quickly begin to lay eggs upon separation from the queen. Reasons for the variability in the response of virgin queens of the different species may be 1) higher probability of reproductive success for unmated dealated queens compared to normal claustral founding in S. invicta and S. richteri linked to relatively frequent loss of the mother queen; or 2) phylogenetic constraint.