Oviposition of the Seed Parasitoid Wasp Macrodasyceras hirsutum (Hymenoptera: Torymidae) into Seeds of Nonhost Tree Ilex latifolia

Abstract

 Both optimality and physiological state models of oviposition behaviour explain a correlation between host plant appearance and host selection in oligophagous insects. To determine whether monophagous herbivores specialising in a single host species exhibit such correlation, 31 females of the seed parasitoid wasp, Macrodasyceras hirsutum Kamijo, whose only host plant is Ilex integra Thunb., were released into an enclosed bag containing berries of the nonhost plant, I. latifolia Thunb., in late May. Dissection of the 45 berries in August revealed that only one endocarp contained a similar-sized larva to the final instar larvae in I. integra seeds. This study indicates that the lack of only one host plant species forces M. hirsutum to oviposit into seeds of the nonhost plant, I. latifolia, and that a hatching larva develops in an I. latifolia seed.