Life History of Macrocheles muscaedomesticae (Acarina: Macrochelidae), a Predator of the House Fly1

Abstract

Macrocheles muscaedomesticae is a free-living predator of the egg, and to a lesser extent of the larva, of Musca doviestica . In the present study, emphasis is placed up standardization of general rearing conditions and a substrate (ground steer manure plus 10% soybean oil meal, moistened) as well as definition of biological performance of this mesostigmatic mite under these conditions. Eggs from virgin females were smaller (0.370 by 0.249 mm.) than eggs from mated females (0.374 by 0.256 mm.), and required a longer incubation period. These individuals spent less time as larvae; neither difference in the first two stages was significant. The protonymphal stage lasted significantly longer in the male progeny from virgin females, while the deutonymphal stage tended to be shorter. However, the total elapsed time from egg to adult for male or female progeny was not significantly different. The preoviposition period in fertilized females (53.5 hours) exceeded that in virgin females (48 hours), but not significantly. Significantly more eggs were laid by virgin females (91.7) than by fertilized females (61.4). The maximum recorded 24-hour egg production from a virgin female was 28, from a fertilized female 25; the average daily production was 7.70 and 5.29, respectively. The average life span of fertilized females (23.9 days) was close to that of unfertilized females (24.3 days) ; the male life span was shorter, averaging 15 days.