Native egg parasitoids on <i>Leptoglossus occidentalis</i> Heidemann (Hemiptera: Coreidae) in Spain: Potential biological control agents?

Leptoglossus occidentalis Heidemann (Heteroptera: Coreidae), commonly known as western conifer seed bug (WCSB), is an invasive pest in the Mediterranean, where it has been associated with decline of Pinus pinea L. kernel production. A biological control WCSB populations native egg parasitoids may reduce economic losses. With purpose to obtaining masses laid situ bags WCSB, adults were placed, for three consecutive years, a clone bank, and 1 year, pine forest Central Spain. To estimate impact parasitoid species on population, four parasitism indexes calculated. The activity period was estimated two years bank through visual monitoring. Two found eggs: Ooencyrtus pityocampae (Mercet) (Hymenoptera: Encyrtidae) obscurus Encyrtidae). latter represents new finding eggs. In discovery efficiency masses, rate eggs, host population exploitation significantly higher O. than pityocampae. forest, index values also obscurus, but significant differences not by species. reduced 6.2%, down 19.6%, while 1.0%, 11.5%. Predated eggs recorded both experimental sites low amounts. Both could be proposed agents (BCA) programme (BCP) Europe after measuring their effectiveness laboratory assessments.