INSECTS ASSOCIATED WITH PURPLE LOOSESTRIFE, LYTHRUM-SALICARIA L., IN SOUTHERN MANITOBA

In 1994 and 1995 insects were collected from several sites in southern Manitoba, where purple loosestrife, Lythrum salicaria L., is dominant . Collection techniques included the use of trap plants, sweep netting , vacuum sampling, and hand collecting. Insects from 38 families were collected and grouped into four general feeding guilds: herbivores, pr edators, omnivores, and fungivores. Herbivores that directly fed on L. salicaria included Galerucella nymphaeae Linne (Coleoptera: Chrysomel idae), Myzus lythri (Schrank) (Homoptera: Aphididae), Poecilocapsus li neatus (Fabricius) (Hemiptera:Miridae), Kleidocerys resedae (Panzer) ( Hemiptera: Lygaeidae), Amerastegia glabrata (Fallen) (Hymenoptera: Ten thredinidae), Orgyia leucostigma (Smith) (Lepidoptera: Lymantriidae), Lophocampa maculata (Harris) (Lepidoptera: Lymantriidae), Spilosoma vi rginica (Fabricius) (Lepidoptera: Arctiidae), Simyra henrici (Grote) ( Lepidoptera: Noctuidae), Dichomeris ligulella (Hubner) (Lepidoptera: G elechiidae), Melanchra picta (Harris) (Lepidoptera: Noctuidae), Hyles galli (Rottenburg) (Lepidoptera: Sphingidae), and Bistort betularia co gnataria (Gn) (Lepidoptera: Geometridae). These herbivores cannot seve rely limit the density of purple loosestrife in southern Manitoba and any interactions with the introduced agents should be minimal. The pre datory stink bug, Apoecilus bracteatus Pitch (Hemiptera: Pentatomidae) , was identified as a potentially important predator of the introduced biological control agents, Galerucella pusilla Duftschmidt and Galeru cella calmariensis (L.) (Coleoptera: Chrysomelidae).