Presence of the fire ant pathogen Kneallhazia solenopsae in fire ant decapitating phorid flies

DAVID H. OI, SANFORD D. PORTER, STEVEN M. VALLES, JUAN A. BRIANO, AND LUIS A. CALCATERRA

Oklahoma, EE.UU

Conferencia; 2009 Imported Fire Ant and Invasive Ant Conference; 2009

Pathogens and parasites from South America are being evaluated for the biological control of imported fire ants in the U.S.  Fire ant decapitating flies that developed in fire ants infected with the fire ant pathogen Kneallhazia (formerly Thelohania) solenopsae also acquired the pathogen.  K. solenopsae was found in 51% of pooled samples, which included three species of flies: Pseudacteon obtusus, Pseudacteon cultellatus, and Pseudacteon curvatus.  The infected P. curvatus were collected from the field in Florida.  This is the first report of a fire ant pathogen being detected in another fire ant biocontrol agent.  K. solenopsae was not detected in any of the hovering or ovipositing flies in laboratory exposures, indicating that mechanical acquisition of the pathogen did not occur during oviposition activity.  Greater than 92% of the P. obtusus that developed in K. solenopsae-infected ants survived and emerged as adults. These preliminary observations indicated there were no detrimental effects of the pathogen on the flies.  The finding of K. solenopsae in apparently healthy flies offers the possibility that the flies can transmit K. solenopsae, and perhaps facilitate the spread of the disease among fire ant populations.