Discovery of Hybrid Fire Ant Populations in Georgia and Alabama

Abstract

The recent movement of fire ants into previously non-infested northwest Georgia counties led to an investigation of their identity. Gas chromatograph traces of the cuticular hydrocarbon patterns of these ants showed them to be hybrids of Solenopsis invicta Buren and Solenopsis richteri Forel. This study extends the known range of the hybrid to ten Georgia counties, twenty-one Alabama counties, and five Mississippi counties.

Developmental stability, heterozygosity, and fitness in two introduced fire ants (Solenopsis invicta and S. richteri) and their hybrid

“…and one in northwestern Georgia (Floyd and Polk Cos.) (see fig. 1; also Ross et a!., 1987b; Diffie et a!., 1988). Populations at these locations previously have been shown to be thoroughly introgressed, the Mississippi population to the extent that it is almost exactly intermediate to the parental species in terms of allele frequencies at diagnostic enzyme loci (Ross et a!., 1987b).…”

“…Trager, unpublished), and venom and hydrocarbon biochemistry (Vander Meer et al, 1985;Ross et aL, 1987b), yet they have formed an extensive zone of hybridization in the south-central U.S.A. (see fig. 1; Diffie et a!., 1988). Given their considerable differentiation for the above traits, it is of interest to determine to what extent S. invicta and S. richteri have diverged in terms of genomic elements coordinating development.…”

Mechanisms of interspecific competition among an invasive and two native fire ants

“…The Argentine ant can still be found in relatively high densities in some isolated areas of the southeastern United States today (e.g., Deyrup et al 1989, Klotz et al 1995, but overall it is not the major pest that it is in California (Ward 1987, Holway 1995. Solenopsis richteri currently is found only in northern Mississippi and Alabama (Diffie et al 1988).…”

Fire ant venom allergy

“…Many of these multiqueen nests appear to be perennial. Although S. invieta initially displaced S. richteri from most of Alabama and Mississippi, the two species have recently been found to form true hybrids (23,70,84,85,86). Limited studies suggest that the hybrids can live at higher altitudes and can tolerate lower temperature conditions than either pure species.…”