Rose stem aphid

Maculolachnus submacula

1. Identification

• Common name: Rose stem aphid
• Scientific name: Maculolachnus submacula Walker
• Order: Hemiptera
• Family: Aphididae

2. Description of the pest

• Apterous adults: Large aphids, robust body, dark brown to black colouration; short, thick siphunculi; shiny body surface.
• Winged adults: Darkened head and thorax; transparent wings; dark brown body; presence of dark patches on the abdomen.
• Nymphs: Similar to apterous adults, but smaller and with a lighter colouration.

3. Main hosts

• Woody species, especially shrubs and ornamental plants.
• Frequent records on vigorous branches and shaded areas of the plant.

4. Symptoms and damage

• General weakening of the plant due to the continuous sucking of sap.
• Reduction of vegetative vigour and delayed growth.
• Abundant production of honeydew, favouring the development of sooty mould.
• Attraction of ants, which can protect the colonies and hinder control.
• Drying of young branches in heavy infestations.

5. Biological cycle

• Species with several annual generations.
• Predominantly parthenogenetic reproduction.
• Development favoured by mild climate and low presence of natural enemies.
• Formation of dense colonies on woody branches, which may persist for much of the year.

6. Monitoring

• Direct observation of young branches and shaded areas.
• Assessment of the presence of honeydew, sooty mould and ant activity.
• Counting of individuals or colonies to support decision-making in integrated protection.

7. Management measures

• Cultural: Pruning and removal of heavily infested branches; elimination of initial foci; improvement of air circulation in the plant.
• Biological: Promotion of natural enemies such as Coccinellidae, Syrphidae and Aphidiinae parasitoids.
• Integrated protection: Intervention only when population levels justify it; preference for selective methods compatible with natural enemies.

Bibliographic references

• Blackman, R. L., & Eastop, V. F. (2000). Aphids on the World’s Crops: An Identification and Information Guide. 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.
• Dixon, A. F. G. (1998). Aphid Ecology: An Optimization Approach. Chapman & Hall.