Worldwide distribution of the mitochondrial diversity in the red fire ant Solenopsis invicta

ASCUNCE, YANG, WU, SHIH, OAKEY, MCCUBBIN, CALCATERRA, SHOEMAKER

Universidad de Florida, Florida, EE.UU.

Conferencia; Post-graduated Conference of the University of Florida; 2009

University of Florida

The Red Imported Fire Ant, Solenopsis invicta, was inadvertently introduced to the U.S.A. from its native South America some 75 years ago. Since that time, it has spread throughout the South and, more recently, to several western states (e.g., New Mexico, California). It also is currently found in Australia, Taiwan, China, Mexico and the Caribbean. One objective of our ongoing research is to use data from multiple genetic markers of different classes (allozymes, microsatellites, mitochondrial and nuclear DNA sequences) to identify the native source population(s) of S. invicta introduced into the U.S.A., Australia, and Asia. For the present study, we examined patterns of mitochondrial DNA (mtDNA) variation within and among native and introduced ant populations. We sequenced a portion of the cytochrome oxidase I gene from 812 workers (1 per nest) collected from 40 geographic populations in the native range and 818 workers collected from 6 localities in the U.S.A. (n=500), 8 sites in Australia (n=99), 2 sites in Taiwan (n=103), and 16 sites in China (n=116). We found a total of 245 different mtDNA haplotypes among all ants surveyed. All worldwide populations shared two common haplotypes (H5 and H22). A third common haplotype (H36) was not found in Australia. Finally, U.S.A presented three more haplotypes that are also found in the native range. Interestingly, one haplotype was identified from individuals from Australia that were not detected among any other surveyed geographic region. In the U.S.A., 10 haplotypes were detected that were absent among other regions.