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ARS Home » Southeast Area » Gainesville, Florida » Center for Medical, Agricultural and Veterinary Entomology » Imported Fire Ant and Household Insects Research » Research » Publications at this Location » Publication #218155
Title: Distributional patterns of Pseudacteon associated with the Solenopsis saevissima complex in South America

Author
item PATROCK, RICHARD - National University Of Quilmes
item Porter, Sanford
item GILBERT, LAWRENCE - University Of Texas
item FOLGARAIT, PATRICIA - National University Of Quilmes

Submitted to: Journal of Insect Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/10/2007
Publication Date: 9/1/2009
Citation: Patrock, R.J., Folgarait, P.J., Gilbert, L.E., Porter, S.D. 2009. Distributional patterns of Pseudacteon associated with the Solenopsis saevissima complex in South America. Journal of Insect Science. 9:60, 17 pp.

Interpretive Summary: Biological control efforts against imported fire ants have so far mostly involved the use of fire ant decapitating flies in the genus Pseudacteon. To facilitate further exploration for new species and new biotypes of these flies, scientists from the National University of Quilmes, Argentina, the University of Texas, and the USDA-ARS Center for Medical, Agricultural and Veterinary Entomology in Gainesville, FL organized a database of collection records for fire ant decapitating flies, including those from the literature and other sources. These data were used to map the geographical ranges of species associated with the imported fire ants in their native range in South America. Approximately equal numbers of Pseudacteon species were found in temperate and tropical regions. No significant differences in sizes of geographical ranges were found between Pseudacteon associated with the different host complexes of the fire ants despite the much larger collection effort associated with fire ants in South America. Flies with the most extensive ranges had either multiple hosts or hosts with broad distributions. Finally, areas in southern South America that have been under-explored for decapitating flies associated with imported fire ants are discussed. This study is important because it will help determine where future efforts to collect new decapitating flies should be conducted.

Technical Abstract: Classical biological control efforts against the imported fire ants have largely involved the use of Pseudacteon parasitoids. To facilitate further exploration for species and population biotypes we organized a database of collection records for Pseudacteon species, including those from the literature and other sources. These data were then used to map the geographical ranges of species associated with the imported fire ants in their native range in South America. In addition, we found geographical range metrics for all species in the genus and related these metrics to latitude and host use. Approximately equal numbers of Pseudacteon species were found in temperate and tropical regions, though the majority of taxa found only in temperate areas were found in the Northern Hemisphere. No significant differences in sizes of geographical ranges were found between Pseudacteon associated with the different host complexes of the fire ants despite the much larger and systemic collection effort associated with the S. saevissima host group. Geographical range of the flies was loosely associated with both the number of hosts and the geographical range of their hosts. Pseudacteon with the most extensive ranges had either multiple hosts or hosts with broad distributions. Mean species richnesses of Pseudacteon in locality species assemblages associated with S. saevissima complex ants was 2.8 species, but intensively sampled locations were usually higher. We discuss possible factors related to variation in geographical range size and outline areas in southern South America that have likely been under-explored for Pseudacteon associated with imported fire ants.