ABUNDANCE OF THE PARASITIC ANT SOLENOPSIS-DAGUERREI (HYMENOPTERA, FORMICIDAE) IN SOUTH-AMERICA, A POTENTIAL CANDIDATE FOR THE BIOLOGICAL-CONTROL OF THE RED IMPORTED FIRE ANT IN THE UNITED-STATES

Abundance of the workerless parasitic ant Solenopsis daguerrei (Santsc hi) in fire ant populations was surveyed in southern and southwestern Brazil, eastern, central, and northern Argentina, western and northern Uruguay, central Paraguay, and Bolivia from 1974 to 1996. A total of 12,180 fire ant colonies was sampled from 726 collecting sites for the presence of adults or queens, or both, of the parasitic ant. The pres ence of the parasite in fire ant colonies within the area surveyed was very low. In Argentina, S. daguerrei occurred in the provinces of Bue nos Aires, Santa Fe, and Entre Bios, in 1.4-7.0% of the colonies. In B razil, the areas of Dourados, Campo Grande, and Rochedo, Mate Grosso d o Sul contained 1-6.2% of parasitized colonies. In Uruguay, <1% of the colonies were parasitized. The parasite was not found in Paraguay and Bolivia. A new host (S. macdonaghi Santschi) is reported for S. dague rrei. The field site with the highest presence of S. daguerrei (7%) wa s selected in Buenos Aires province for ecological studies. The low pr esence in its native areas should not discourage the potential use of this parasite as a biological control agent of imported fire ants in t he United States.