Chloridolum thomsoni

Chloridolum thomsoni is a species of longhorn beetle (family Cerambycidae) known to be a significant pest for various woody plants. Primarily found in East Asia, this insect poses a serious threat to the vitality of citrus orchards by colonizing the trunks and primary branches of trees.

The host range is largely concentrated on citrus species, including oranges, mandarins, and grapefruits. The beetle thrives in orchard environments where it finds suitable host tissue, often preferring trees that are already stressed or have existing bark injuries that facilitate the egg-laying process.

The biology of the species centers on its larval stage, which acts as a wood-borer. Females oviposit on the surface of the bark, and upon hatching, the larvae tunnel directly into the cambium and heartwood. This invasive behavior allows the insect to remain largely hidden from predators and external contact insecticides for the duration of its development.

The primary damage is caused by the larval mining activity, which severs vascular bundles and prevents the transport of water and nutrients throughout the tree. Visible symptoms include the presence of frass at the base of the tree, sap weeping, and, in severe cases, branch dieback and overall tree death.

Integrated pest management strategies for this beetle include:

• Regular orchard monitoring to identify early signs of infestation such as exit holes or frass.
• Pruning and destroying infested plant material to reduce the pest population density.
• Maintaining tree vigor through proper fertilization and irrigation to improve natural defense mechanisms.
• Targeted application of systemic insecticides during the peak flight period of adult beetles to interrupt the reproductive cycle.