STUDIES ON THE LIFE-HISTORY OF SOME SPECIES OF PROTOCALLIPHORA (DIPTERA, CALLIPHORIDAE)

The rate of development of the larvae, postfeeding larvae, puparia, and adults of 10 species of Protocalliphora were studied and differences noted in the rates of development and (or) survival. Larvae of Protocalliphora were photonegative and strongly influenced by thigmotactic stimuli. The method of feeding of the larva is described. Metamorphosis was completed more quickly at higher temperatures than at lower temperatures. Survival of purparia at temperatures of 7-degrees-C or lower was poor and indicated that this stage was not adapted to withstand low temperatures and probably did not survive the winter. Adult Protocalliphora females were longer lived than males, surviving for an average of 70-100 days, with some individuals surviving for over 250 days under laboratory conditions. Adults fed readily on a sugar-protein diet, crushed berries, and certain species of flowers, but most species did not feed on any form of carrion. Adults mated readily in captivity, but none of the seven species tested crossbred. Spermatozoa remained motile in the seminal receptacles for over 100 days. Eggs were laid on a few occasions, but the factors determining egg production were not studied. Adult Protocalliphora were strongly photopositive and became quiescent in the dark. Adult flies rarely became active until a threshold temperature of 15.5-degrees-C; different species had differing threshold temperatures. Adults successfully overwintered in a single field trial.