Zeuzera / Leopard moth

Zeuzera pyrina

1. Identification

• Common name: Leopard moth / Borer
• Scientific name: Zeuzera pyrina L.
• Order: Lepidoptera
• Family: Cossidae

2. Pest description

• Medium‑sized lepidopteran; white adults with bluish or black spots on the wings.
• Xylophagous larvae, light‑coloured with dark spots, penetrating into branches and trunks.
• Highly destructive pest in fruit trees and other woody species, producing deep galleries.
• Prolonged larval activity, which may extend over several months.

3. Main hosts

• Pome fruits: apple, pear, quince.
• Other fruit trees: walnut, loquat, almond, pomegranate, olive, carob, hazel.
• Ornamentals and forest trees: lime, ash, Japanese maple, poplar, elm, azalea.

4. Symptoms and damage

• Entry and exit holes in the limbs and trunks.
• Expulsion of coarse sawdust mixed with excrement.
• Drying of branches, breakage from fragility and general decline of the tree.
• In young trees, a single larva can cause the death of the plant.
• In mature trees, it increases susceptibility to wind and to other secondary pests.

5. Biological cycle

• Adults appear from late spring to summer.
• Females lay large masses of eggs, frequently over 1000.
• Larvae quickly penetrate the branches, where they build deep galleries.
• They overwinter inside the wood, resuming activity the following spring.
• Normally 1 generation per year; in cold regions the cycle may extend over 2 years.

6. Monitoring

• Installation of pheromone traps (funnel or delta type) for detection of males.
• Observation of sawdust and holes in the branches.
• Reinforced monitoring between May and September.
• Use of 1–2 traps/ha for population tracking.

7. Management measures

• Cultural: removal and destruction of attacked branches; elimination of cut wood; reinforcement of the tree's vitality.
• Preventive: pruning at suitable times; avoid water stress; regular inspection of young trees.
• Biological: use of pheromones for mating disruption.
• Integrated protection: judicious application of authorised insecticides during the larval hatching period; integration with cultural practices and continuous monitoring.

Bibliographic references

• EPPO Global Database – Zeuzera pyrina.
• CABI – Invasive Species Compendium – Zeuzera pyrina.
• Alford, D. V. (2007). Pests of Fruit Crops: A Colour Handbook. Manson Publishing.
• Trematerra, P. (1990). Monitoring and control of Zeuzera pyrina in fruit orchards. Journal of Applied Entomology.
• Avilla, J. & Bosch, D. (2013). Lepidopteran borers in fruit trees: biology and management. IOBC‑WPRS Bulletin.