Interspecific Interactions Between Orius insidiosus (Heteroptera: Anthocoridae) and Leptothrips mali (Thysanoptera: Phlaeothripidae)

The interspecific interactions of 5th-instar Orius insidiosus (Say) and 2nd-instar larvae of another mite predator, Leptothrips mali (Fitch), was studied in the laboratory. L. mali is a potential prey for O. insidiosus , but has a defensive anal secretion which repels predator attacks. Most contacts between well-fed O. insidiosus and L. mali resulted in mutual avoidance. Most attacks by O. insidiosus were unsuccessful, especially if the approach was from the rear. Contact with the thrips' anal secretion resulted in immediate repelling of O. insidiosus , with subsequent cleaning activity lasting 1 to 3 min. This study indicates that these two predators are compatible, especially in the presence of another food source such as the European red mite.