In western North America, infestations of the hemlock woolly adelgid, Adelges tsugae Annand (Hemiptera: Adelgidae), are common on orchard, ornamental, and roadside western hemlock, Tsuga heterophylla (Raf.) Sargent. However, these infestations rarely cause T. heterophylla mortality.Host tolerance andpresence of endemic predatorsmaybe contributing to the relatively low levels of injury to T. het...

Omnivory is common among arthropods, but little is known about how availability of plant resources and prey affects interactions between species operating at the third and fourth trophic level. We used laboratory and field cage experiments to investigate how the provision of flowers affects an omnivorous lacewing, Micromus tasmaniae (Hemerobiidae) and its parasitoid Anacharis zealandica (Figiti...

Longitudinal folding (plaiting) of forewings at rest has arisen independently in Vespidae, Colletidae, Gasteruptiidae, Figitidae, Leucospidae, and Pompilidae. In the first five families the plaiting fold is similar in position, but in the last family its position is different. A type of wing folding unique to the eucoilid genus Kleidotoma—wrapping flexure—is described. In all cases, evolution o...