ARS | Publication request: Distribution of the Formosa strain of the fire ant decapitating fly Pseudacteon curvatus (Diptera: Phoridae) three and a half years after releases in North Florida

Submitted to: Florida Entomologist
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: November 16, 2009
Publication Date: March 1, 2010
Citation: Porter, S.D. 2010. Distribution of the Formosa strain of the fire ant decapitating fly Pseudacteon curvatus (Diptera: Phoridae) three and a half years after releases in North Florida. Florida Entomologist. 93(1):107-112.

Interpretive Summary: The decapitating fly Pseudacteon curvatus was released and successfully established as a self-sustaining biocontrol agent of the red imported fire ant Solenopsis invicta at four sites around Gainesville, FL in 2003. In order to determine the status of these releases, a research entomologist with the USDA Agricultural Research Service at the Center for Medical, Agricultural and Veterinary Entomology in Gainesville, FL surveyed 59 sites for decapitating flies in the fall of 2006 using sticky traps and aspirators. Results of this survey showed that the flies had expanded out an average of 46 miles and occupied almost 12,000 square miles in North Central Florida. This rate of expansion was faster than rates reported for a previously released species of decapitating fly (Pseudacton tricuspis) in Florida, Louisiana, and Texas. The rapid rates of expansion and high densities reported for the new species of decapitating fly (P. curvatus) indicate that it is a vigorous parasitoid which will require relatively fewer field releases to establish it as biocontrol agent of red imported fire ants in the United States.

Technical Abstract: The Formosa biotype of the decapitating fly Pseudacteon curvatus Borgmeier was released and successfully established as a self-sustaining biocontrol agent of the red imported fire ant Solenopsis invicta Buren at several sites around Gainesville, FL in 2003. In order to determine the status of these releases, 59 sites were surveyed for flies in the fall of 2006 using sticky traps and aspirators. Results of this survey showed that the flies had expanded out an average of 74 km and occupied more than 30,000 km2 in North Central Florida. This rate of expansion was faster than rates reported for Pseudacton tricuspis Borgmeier in Florida, Louisiana, and Texas. The rapid rates of expansion and high densities reported for the Formosa biotype of P. curvatus indicate that it is a vigorous parasitoid which will require relatively fewer field releases to establish it as biocontrol agent of red imported fire ants in the United States.