The life cycle of the emerald ash borer Agrilus planipennis in European Russia and comparisons with its life cycles in Asia and North America

1 Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), native to Asia, is a destructive invasive pest of ash Fraxinus spp. in U.S.A., Canada and European Russia. It is spreading quickly and will probably soon be detected in other European countries. 2 Information about the life cycle of the pest is needed for detection and survey efforts, development of control options and predicting the potential range in Europe. The life cycle has been studied in North America and Asia, although it has not previously been studied in European Russia. 3 The number of larval instars and the duration of development of A. planipennis in European Russia were determined. Distributions of width of epistome and length of urogomphi indicated four larval instars. The number of excretory ducts and the presence of ledges did not provide a clear differentiation between instars. Development in most of the specimens took 2 years. 4 Generation time is flexible. In warmer regions (Tianjin), most individuals finish development in 1 year, whereas, in colder regions (Moscow, Changchun, Harbin), it takes 2 years. In intermediate climatic regions (Michigan), the ratio of 1 : 2-year life cycles depends on additional factors. The flexibility of the life cycle allows A. planipennis to establish in regions with different climates.