Behavioral observations on the adults and larvae of Leucopis ninae and L-gaimarii (Diptera: Chamaemyiidae), predators of Russian wheat aphid, Diuraphis noxia (Homoptera: Aphididae)

Behavior was observed on the immature and adult stages of Leucopis ninae and L. gaimarii (Diptera: Chamaemyiidae). The searching and feeding behavior of each larval instar is discussed. The first instars usually attacked aphids that walked over them, while second and third instars more actively searched out prey. Larvae were observed to hunt diurnally, becoming inactive at night. Cannibalism was found to be quite common, even within large aphid populations. The molting and pupariation processes are described including methods for adhering molting larvae and puparia to their substrata. Courtship behavior was observed, including male wing fluttering, wing extension, and touching, and female responses, such as wing fluttering and pushups in front of the male. Oviposition behavior seemed consistent with published accounts, but we found that females could oviposit directly into the fold of a wheat leaf rolled by feeding of the Russian wheat aphid, Diuraphis noxia (Homoptera: Aphididae).