Four species of lady beetles (Coleoptera: Coccinellidae) exhibit limited predation on Nezara viridula (Hemiptera: Pentatomidae) eggs and nymphs

Abstract

The Coccinellidae (Coleoptera) co-occur in many habitats with many arthropods that are of suitable size as prey. The Pentatomidae (Hemiptera) are one such group of insects with eggs and early instars that could be susceptible to predation by Coccinellidae. The objective of this laboratory study was to examine if predation by adult and larval Coccinellidae occurred on the eggs and 1st instars of Nezara viridula (L.) (Hemiptera: Pentatomidae). We tested whether live eggs, live nymphs, or dead nymphs (recently frozen) would be fed on by Coleomegilla maculata, Harmonia axyridis, Hippodamia convergens and Olla v-nigrum (Coleoptera: Coccinellidae). Our results show that starved 4th instars and adults of all tested Coccinellidae cannot feed on N. viridula eggs. More feeding by larval lady beetles occurred on recently frozen, dead 1st instars than on live 1st instars. The exception to this was larval C. maculata which fed similarly on live and dead nymphs. Adult lady beetles did not feed on live 1st instar N. viridula. Observations indicated that in some instances, a live N. viridula nymph was capable of repelling a predator. From this study, it is unlikely that the Coccinellidae contribute to substantial predation of N. viridula eggs and nymphs.