Cork oak buprestid borer

Coroebus undatus

1. Identification

• Common name: Cork oak jewel beetle
• Scientific name: Coroebus undatus Fabricius
• Order: Coleoptera
• Family: Buprestidae

2. Pest description

• Metallic adults, elongated, about 8–12 mm; coppery-green colouration.
• Apodous larvae, whitish, with the flattened body typical of buprestids.
• Eggs laid in cracks of the cork oak bark.

3. Main hosts

• Cork oak.
• Occasional attacks on holm oak.

4. Symptoms and damage

• Sinuous galleries in the inner layer of the cork (“wave galleries”).
• Commercial devaluation of the cork due to the marks left by the larvae.
• Localised weakening of the rhytidome.
• Higher incidence in weakened trees or with lower quality cork.

5. Biological cycle

• Winter spent as a larva inside the cork.
• Prolonged larval development, generally 1 to 2 years.
• Pupation in the cork itself.
• Adults emerge in summer.
• Females lay eggs in cracks and rough areas of the bark.

6. Monitoring

• Observation of characteristic galleries after the extraction of the cork.
• Assessment of the intensity of attack through visual inspection of the rhytidome.
• Recording of areas and plots with higher incidence for future management.

7. Management measures

• Good cork extraction practices, avoiding excessive wounds.
• Maintenance of tree vigour through proper management of the cork oak woodland.
• Removal of severely weakened trees that act as infestation foci.
• Planning of cork harvesting to minimise the economic impact of the attacks.

Bibliographic references

• EPPO Global Database – Coroebus undatus.
• CABI Invasive Species Compendium – Coroebus undatus.
• Branco, M. et al. (2010). Pragas do montado de sobro.
• Sousa, E. & Naves, P. (2001). Buprestídeos associados ao sobreiro em Portugal.