Effect of sugar feeding on the lifespan of four phorid fly species: Pseudacteon cultellatus, P. curvatus, P. obtusus, and P. tricuspis - natural enemies of imported fire ants

The phorid flies, Pseudacteon cultellatus, P.curvatus and P. obtusus  (Diptera: Phoridae), are introduced parasitoids of imported fire ants, Solenopsis spp. in the southeastern United States. The longevity of the three species was compared under four diet treatments: 50% sucrose solution, 25% sucrose solution, sugar starved, and completely starved. Water was provided in all treatments except the completely starved. Completely starved flies rarely lived beyond one day. Sugar starved flies have an average longevity of 3 days. Flies fed either 25% or 50% sucrose solution have the highest longevity, and this was true for all three species. Comparing the species, P. obtusus and P. cultellatus have significantly higher longevity than P. curvatus. No significant sexual differences were recorded. Sugar feeding significantly increased the longevity of P. obtusus and P. cultellatus probably because they are both synovigenic species. Future studies will investigate the ovigeny index of these flies, and the effect of sugar feeding on their fecundity.