Cryptocephaline Egg Case Provides Incomplete Protection from Generalist Predators (Coleoptera: Chrysomelidae)

Abstract

The egg case of Cryptocephalus rufipes (Goeze) is described and illustrated. In laboratory trials, eggs of field-collected C. rufipes were observed for larval emergence (untreated control) or exposed to two species of generalist predators, Chrysoperla carnea (Stephens) or Xylocoris flavipes (Reuter) in no-choice experiments. The behaviour of the predators upon contact with the C. rufipes eggs was observed. The number of hatching larvae was counted and compared. In the presence of each of the two species of predators, larval emergence was significantly reduced. Eggs that were not protected by an egg case were completely consumed by the predators. C. rufipes eggs were therefore incompletely protected from the studied generalist predators. This is the first study showing experimentally the protective function of cryptocephaline egg case.