Green citrus aphid

Aphis spiraecola

1. Identification

• Common name: Green citrus aphid
• Scientific name: Aphis spiraecola Patch
• Order: Hemiptera
• Family: Aphididae

2. Pest description

• Apterous adults: Small, bright green body; relatively long antennae; dark siphunculi; pale cauda; compact colonies on young leaves.
• Alate adults: Darkened head and thorax; transparent wings; yellowish-green body; venation typical of the genus Aphis.
• Nymphs: Similar to apterous adults, but smaller and with more uniform colouration.

3. Main hosts

• Primary hosts: Citrus.
• Other hosts: Spireas (Spiraea spp.), pear, apple, quince and various ornamentals.
• Occasional secondary hosts: Various herbaceous plants, depending on the region.

4. Symptoms and damage

• Curling and deformation of young leaves.
• Reduced growth of new shoots.
• Formation of dense colonies on tender leaves and buds.
• Excretion of honeydew, favouring sooty mould.
• Potential transmission of viruses in citrus and other fruit trees.

5. Biological cycle

• Species with several annual generations.
• Predominantly parthenogenetic reproduction.
• Frequently anholocyclic cycle in warm regions, remaining active all year round.
• Populations increase in mild weather and on young, vigorous shoots.

6. Monitoring

• Direct observation of young and curled leaves.
• Assessment of the presence of colonies, honeydew and sooty mould.
• Counting of individuals per shoot to support decision-making in integrated protection.

7. Management measures

• Cultural: Removal of heavily infested shoots; clean-up pruning; avoiding excess vegetative vigour.
• Biological: Conservation of beneficials such as Coccinellidae, Syrphidae, Chrysopidae and Aphidiinae parasitoids.
• Integrated protection: Intervention only when population levels justify it; preference for selective methods compatible with beneficials.

Bibliographic references

• Blackman, R. L., & Eastop, V. F. (2000). Aphids on the World’s Crops. Wiley.
• Blackman, R. L., & Eastop, V. F. (2006). Aphids on the World’s Herbaceous Plants and Shrubs. Wiley.
• van Emden, H. F., & Harrington, R. (2017). Aphids as Crop Pests (2nd ed.). CABI.
• EPPO Global Database. Aphis spiraecola.
• CABI Invasive Species Compendium. Aphis spiraecola.