Contributions To The Natural History Of Scelio Fulgidus Crawford (Hymenoptera: Platygastridae)

Abstract

Scelio fulgidus (Crawford, 1911) is a solitary hymenopteran egg parasitoid of the Australian plague locust (Chortoicetes terminifera (Walker, 1870)) and an important contributor to biotic population regulation in its primary host. The history of scientific research on the species is reviewed. Laboratory trials tested a number of aspects of S. fulgidus life history. Development duration from egg to adult was measured over a range of constant temperatures from 18–34°C. Complete development takes 4–6 days longer than C. terminifera embryonic development over the 24–34°C range, but diverges markedly below 24°C. Hatching takes over 300 days at 20°C and development is suspended at 18°C. Single females achieved complete parasitism of host pods in 80% of trials and females can parasitise 3 host pods in sequence. At 25°C, host egg pods were detected and parasitised up to 2 weeks after laying, therefore affecting all locust embryo stages up to and including anatrepsis, the rotation and inversion of the embryo position within the egg. Sibling mating produced male-biased sex ratios in offspring, outnumbering females after 2 generations. Show more