Beetle / Red Palm Weevil

Rhynchophorus ferrugineus

1. Identification

• Common name: Red palm weevil
• Scientific name: Rhynchophorus ferrugineus Olivier
• Order: Coleoptera
• Family: Dryophthoridae

2. Pest description

• Adults: Large beetles (≈ 2–5 cm); reddish to rusty-brown colouring; long, curved rostrum; geniculate antennae.
• Larvae: Apodous, cream-yellowish body, brown head, up to 5 cm; robust and fleshy in appearance.
• Eggs: White, oval, laid in wounds, leaf axils or leaf bases.

3. Main hosts

• Palms of the genus Phoenix (especially P. canariensis and P. dactylifera).
• Washingtonia spp.
• Cocos nucifera (in tropical regions).
• Other susceptible Arecaceae to a lesser extent.

4. Symptoms and damage

• Borings and deep galleries in the stipe and at the leaf bases.
• Exudation of fermented liquids, chewed fibres and brown residues.
• Central leaves drooping, misaligned or with abnormal growth (“open crown”).
• Wilting and structural collapse of the crown.
• Death of the palm in advanced attacks, often without early external symptoms.

5. Biological cycle

• Continuous development in mild climates; 2–3 generations per year.
• Eggs laid in wounds or soft areas of the stipe.
• Larvae bore extensive galleries inside the palm, where they complete their development.
• Pupation in fibre cocoons built inside the plant.
• Adults emerge and disperse actively; strong flight capacity.

6. Monitoring

• Specific traps with pheromones and aggregation attractants for detection and population tracking.
• Visual inspection of palms for signs of exudation, loose fibres and crown deformations.
• Acoustic listening (in technical contexts) for detection of larvae inside the stipe.
• Historical records of the holding and reinforced surveillance in areas with known outbreaks.

7. Management measures

• Cultural: These include the removal of heavily attacked palms, removal and destruction of infested tissues and prevention of wounds on the stipe. Pruning should be carried out during periods of lower pest activity and with protection of the cut surfaces. Cleaning of plant debris and proper waste management reduce the attractiveness for oviposition.
• Biological: These are based on the use of entomopathogenic nematodes (e.g.: Steinernema spp., Heterorhabditis spp.) applied in areas of larval activity. Entomopathogens such as Beauveria bassiana have shown complementary efficacy. The conservation of natural enemies and the reduction of broad-spectrum insecticides favour biological control.
• Integrated protection: This is based on monitoring with pheromones, early detection and selective intervention. Treatments should be synchronised with the periods of greatest adult activity. Localised application of insecticides at entry points or galleries may be necessary in specific situations. The integration of cultural and biological practices and continuous monitoring is essential to reduce the risk of palm mortality.

Bibliographic references

• EPPO Global Database – Rhynchophorus ferrugineus.
• CABI Invasive Species Compendium – Rhynchophorus ferrugineus.
• Ferry, M. & Gómez, S. (2002). The red palm weevil in the Mediterranean area.
• EFSA Panel on Plant Health (2019). Pest categorisation of Rhynchophorus ferrugineus.
• Faleiro, J.R. (2006). A review of the issues and management of the red palm weevil.
• Soroker, V. et al. (2013). Current status of the red palm weevil threat to date palm plantations.