title: Early season dispersal of Muscidifurax zaraptor (Hymenoptera: Pteromalidae) utilizing freeze-killed housefly pupae as hosts.
abstract: The pteromalid wasp, Muscidifurax zaraptor Kogan and Legner, was released at three locations at a dairy in May before housefly and stable fly breeding had begun. Freeze-killed housefly pupae were placed adjacent to the emerging parasites at biweekly intervals for a 6-week period. Hosts placed out weeks 0 and 2 were heavily parasitized. Decreased parasitism in hosts placed out at week 4 suggested that many of the M. zaraptor had dispersed or died. High parasitism of hosts placed in the field at week 6 was the result of second generation parasites emerging from pupae placed out at week 0. Parasitism of freeze-killed housefly pupae placed 6 m and in the four cardinal directions from the release points was similar but lower than for hosts placed adjacent to the emerging parasites. The study demonstrated that emerging M. zaraptor readily utilized nearby freeze-killed housefly pupae but the availability of these hosts did not deter the parasites from searching for additional hosts.
authors.affiliation: Department of Entomology, University of Nebraska, Lincoln 68583-0816.
authors.forename: J J
authors.initials: JJ
authors.lastname: Petersen
authors.forename: B M
authors.initials: BM
authors.lastname: Pawson
mesh_terms: D000818:Animals; D005260:Female; D005615:Freezing; D009117:Muscidae / Q000469:parasitology*; D010058:Oviposition; D011679:Pupa / Q000469:parasitology; D012621:Seasons; D014863:Wasps / Q000502:physiology*