THE REPRODUCTIVE STATUS OF CHRYSOMYA SPECIES (DIPTERA: CALLIPHORIDAE) ATTRACTED TO LIVER‐BAITED BLOWFLY TRAPS IN PAPUA NEW GUINEA

Abstract

The reproductive status of five species of Chrysomya caught in liver‐baited traps in Papua New Guinea was determined. The species trapped were the Old World screw‐worm fly, Chrysomya bezziana Villeneuve and the blowflies, C. megacephala (F.), C. saffranea (Bigot), C. rufifacies (Macquart) and C. varipes (Macquart). The results were compared with data obtained by other workers for the Australian sheep blowfly, Lucilia cuprina (Wiedemann) and the American screw‐worm fly, Cochliomyia hominivorax (Coquerel). Of the total Chrysomya catch, only 0.04% were C. bezziana. Of the 108 C. bezziana trapped only one was male, compared with 17‐26% males in the other species. This demonstrated that the male screw‐worm fly is relatively unresponsive to sources of protein. Nulliparous females accounted for 9% of the total C. bezziana catch, compared with 53‐76% for the blowfly species. This is related to the autogenous nature of the screw‐worm fly, which does not require protein during the first ovarian cycle. Gravid females accounted for 12% of the C. bezziana catch compared with 21 ‐50% in the other Chrysomya species, 14% in L. cuprina and 5% in C. hominivorax. Of the second ovarian cycle flies trapped, 98% of the C. bezziana were in the early stages of egg development compared with 43‐62% in the blowfly species and C. hominivorax. Copyright © 1979, Wiley Blackwell. All rights reserved