Prey of Symmorphus Wasps (Hymenoptera: Eumeninae) in Lithuania

Abstract

The studied populations of six solitary predatory wasps of the subfamily Eumeninae show a different degree of prey choice specificity. Symmorphus murarius and S. crassicornis may be considered as nearly monophagous, hunting only larvae of Chrysomela and sometimes closely related Linaeidea. S. allobrogus provisions its nests mainly with prey of Chrysomelinae leaf beetle larvae from the genera Linaeidea, Gonioctena, Phratora and Plagiodera. S. bifasciatus preys mostly on larvae of Phratora species, sometimes catching Linaeidea and Plagiodera as well. The latter two wasp species may be regarded as oligophagous. Another broadly oligophagous species, S. debilitates, hunts mining larvae of Microlepidoptera of several families. S. allobrogus, S. bifasciatus, S. crassicornis and S. murarius seek their phytophagous prey on leaves of various deciduous trees and shrubs. These wasps do not show a clear preference for a particular plant species and sometimes provision the same nest, or even the same cell, with prey from different food plants. The monophagous S. gracilis hunts its only prey, larvae of the weevil Cionus sp., on the herbaceous plant, Scrophularia sp.