Patterns of Host Specificity in Pseudacteon Parasitoid Flies (Diptera: Phoridae) that Attack Solenopsis Fire Ants (Hymenoptera: Formicidae)

Environ. Entomo!. 26(5): 1149-1154 (1997) ABSTRACT Pselldacteon phorids that parasitize the red imported fire ant, Solenopsis invicta Buren, inSouthAmericaare not present in the introduced range ofthispest speciesin the United States. Sequential host specificity tests were conducted with 4 South American Pselldacteon species, P. litoralis Borgmeier, P. wasmanni (Schmitz), P. triCllspis Borgmeier, and P. curvatlls Borgmeier, to investigate the degree to which these species attack the native North American fireant, Solenopsis geminata (F.). Three species,P. litoralis, P. wasmanni, and P. triCllspis,showed little interest in ovipositingon S.geminata, even when highlymotivated to ovipositon S.invicta. Bycomparison,P. Cllroatus oviposited on S.geminata readily. Larvaldevelopment of P. cllroatlls did occur in S.geminata, but no adult flies emerged. Methods for assayinghost specificity and the biocontrol potential of these unique insects are discussed.