Abstract: The tachinid fly Nemorilla maculosa Meigen (Diptera: Tachinidae) is an important parasitoid of the beet webworm, Loxostege sticticalis L. (Lepidoptera: Pyralidae) and other lepidopterous pests. Bionomics of this parasitoid, however, has been less understood. The emergence, mating duration, lifetime fecundity and lifespan of N. maculosa adults in relation to various types of supplemental nutrition were investigated under laboratory conditions (22℃, L16∶D8). The results showed that N. maculosa adults emerge mostly during hours of 08: 00-10: 00 and 14: 00-16: 00 of the day although they could emerge at any time of the day. Males emerge usually one day earlier than females. Males mate at the second day after emergence while females mate immediately after emergence. Mating duration of the fly could last 10-54 min but mostly last 20-30 min. Number of eggs laid per female is 154.1 on average. Longevity of female and male is 26.6 and 10.2 days on average, respectively, and differs significantly under the same environmental condition. The preoviposition period of females is 3.8 days on average, and the durational time of egg-laying is 15.5 days on average. Feeding with 10% honey, glucose and sucrose solution showed no significant effect on lifetime fecundity of N. maculosa adults, but the flies fed with water or pure hungered laid significantly less eggs than those fed with sugar solution mentioned. Lifespan of female flies fed with various types of supplemental nutrition were significantly greater than that fed with only water or nothing. Lifespan of the males, however, was not significantly different whether they were fed with supplemental nutrition or not. Lifetime fecundity of the female adults was significantly and positively correlated to their lifespan when they were fed with various types of supplemental nutrition. The significances of these findings were finally discussed.

Key words: Nemorilla maculosa, Loxostege sticticalis, adult fly, biology, supplemental nutrition