Chemical mediation of egg dumping in the lace bug Gargaphia solani Heidemann (Heteroptera : Tingidae)

We tested the hypothesis that the proximate cue for egg dumping in the lace bug Gargaphia solani Heidemann is a chemical deposited by females on eggs during or shortly after oviposition. The results of this study show that: ( 1) dumping frequency declines as eggs age but can be elevated to its highes t levels by exposure to chemical extracts from young egg masses; and (2) vi sual cues are not necessary to stimulate dumping. Further data support the hypothesis that the ovipositional chemical is used by egg dumpers as a long -distance signal of an appropriate oviposition site, and is not a mechanism by which guarding females relocate their eggs if separated from them. (C) 1998 The Association for the Study of Animal Behaviour.