The parasitic nematode Howardula aoronymphium causes severe fertility reduction and sterility in females of several species of mycophagous Drosophila. Infected females of Drosophila putrida recover their fertility when kept at a postemergence temperature of 29 C but not when kept at 27 C or below. When given a choice of temperatures in a thermal gradient, neither this species, Drosophila falleni, nor Drasophila neotestacea manifested adaptive behavioral fever in response to parasitism. However, our conclusions concerning D. neotestacea and D. falleni remain tentative because of small sample sizes.