none Aphaereta pallipes was recovered from nine species of dung-breeding Diptera during field studies in central Missouri. The principal hosts, as measured by total percent parasitism, were Ravinia querula (Walker), R. lherminieri (Robineau-Desvoidy), and Ravinia-Oxysarcodexia spp. (Diptera: Sarcophagidae). Successful emergence of adult A. pallipes from host puparia was greatest in Ravinia-Oxysarcodexia spp. R. lherminieri , and Orthellia caesarion (Meigen) (Diptera: Muscidae). Considering both host abundance in the field and the calculated average production of emergent parasite adults from such host puparia, it was determined that Q. caesarion could be predicted to account for ca. 75% of the adult A. pallipes population on central Missouri pastures.