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Citrus longhorn beetle (Anoplophora chinensis)

The citrus longhorn beetle, Anoplophora chinensis (Forster), is a non-native pest that is extremely damaging to a wide range of broadleaved trees and shrubs. It is a quarantine pest for the European Union. The natural range of the beetle includes China, Japan and other countries in South East Asia. Citrus longhorn beetles have been moving around the world in ornamental trees from Asia. They pose a serious threat to horticulture, forestry and native trees in the UK.

The threat

Although there are no known outbreaks of the beetle in the UK, the numerous interceptions since 2005 and outbreaks in Europe demonstrate that there is a significant threat to the UK.


Adult beetles are large and black with variable white markings. Their antennae are particularly distinctive, longer than their bodies (between 1.2–2 times body length) and black with white/light blue bands. The larval stage of the beetles is the most damaging. The larvae feed internally on the pith and vascular systems of the lower trunk and root.

The tunnels created by the feeding leave trees susceptible to diseases and wind damage. The adults can cause more limited damage by feeding on foliage and eating young bark. Citrus longhorn beetles spend most of their life, as larvae inside a trunk or root, and hence there can be little or no external sign of their presence to anyone inspecting a host tree.


Images and description (Fera website)


Their lifecycle can be one to two years in Asia, however in the UK the lifecycle is likely to be at least two years and more likely three or more years as in the Netherlands.

Susceptible trees

Citrus longhorn beetle has an extensive host range of deciduous trees and shrubs including many species native to the UK and species grown as ornamentals. In 2008, the EU Commission passed emergency measures aimed at stopping the introduction and spread of this pest within the Community. The Decision referred specifically to the following trees and shrubs which are known to be the most significant hosts of citrus longhorn beetle: Acer spp. (maples), Aesculus hippocastanum (horse chestnut), Alnus spp. (alder), Betula spp. (birch), Carpinus spp. (hornbeam), Citrus spp., Corylus spp. (hazel), Cotoneaster spp., Fagus spp. (beech), Lagerstroemia spp., Malus spp. (apple), Platanus spp. (plane), Populus spp. (poplar), Prunus spp. (cherry etc.), Pyrus spp. (pear), Salix spp. (willow), and Ulmus spp. (elm).

More information (Fera website)

Reporting suspected cases


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Last updated: 11th July 2017