Studies on the oviposition and longevity of Ilione albiseta [Dipt. Sciomyzidae] - Potential biological control agent of liver fluke

The effect of 5 constant temperatures (10, 14, 17, 20 and 23°C) on the oviposition and longevity of Ilione albiseta was investigated. Most eggs were laid at 14-17°C and mean oviposition period declined progressively above and below 14°C. There was no significant difference between oviposition rates or preoviposition periods at each constant temperature, but the mean number of days between egg laying for each female was significantly greater at 10 °C than at 17, 20 and 23 °C than at 20 °C. The percentage of infertile eggs laid ranged from 9.2% at 23 °C to 17.9 % at 20 °C and these eggs tended to be laid at the beginning and end of each oviposition period. A possible association between sex ratio of the emergent adult and temperature is also discussed.