Forest Research Schematic diagram of the life cycle of Agrilus biguttatus on native oak trees in Britain - from egg to adult Sandra Denman and Nathan Brown, Forest Research As temperatures warm up, larvae continue to feed and grow, in widening galleries. As larvae ‘outgrow’ their skin they go through a moulting phase Early instar larvae enter Year 1 continued to a bigger size or ‘instar’. The fi rst overwintering period larvae go through 5 instar Feb M phases before pupation. n ar Ja A pr ec D M ay ov N Larvae approach Acute oak decline (AOD) is a condition of mature fully grown status native oak in Britain that appears to be increasing. 2 Aff ected trees are identifi ed by symptoms of t uly c J r a e profuse stem bleeding and signifi cant tree O y Larvae migrate to outer bark g Ju u n A o mortality. Two organisms are thought to play key e t Year 2 for 2nd overwintering, in pupal in g roles in AOD; bacteria and the buprestid beetle chamber in bark plate n i o g In warmer climates Agrilus biguttatus. This poster describes the life p e p development may S cycle of Agrilus biguttatus in Britian. e be completed in S Eggs hatch and larvae feed on one year O the cambial tissues creating c t sinuous galleries. N ov De A c u Ja Apr Females lay eggs in bark crevices g n F ar eb M Pupation takes place, adult ready for J emergence uly ay M START M year 1 id-en d June June Adults emerge Names Mating and egg laying begins Adult beetles feed on foliage in canopy. Agrilus biguttatus (syn. Agrilus pannonicus) on weakened trees. Common names: 1) Two-spotted oak buprestid (Br.) 2) Oak jewel beetle (De.) 3) Oak splendor beetle (USA) D-shaped exit hole is visible Note on the bark Females have a long ovipositor () enabling eggs plate. Jewel beetle is the common name of the to be placed deep in bark cracks. family Buprestidae. Agrilus biguttatus is native to Britain, Europe Photo credits: and North Africa. Forest Research and Nathan Brown, except mating adults (TDP Invertebrate Surveyors and Consultants Ltd) and Pupa (Nikola Rahmé, buprestidae.blogspot.com) Acknowledgements: The authors thank the Forestry Commission, Woodland Heritage and the Ruff ord Foundation for funding this poster. FR(AD-SD)/GA1/AUG11/0109 © Crown Copyright 2011 The Research Agency of the Forestry Commission.