Tropical garden ant

Systematic position. This species belongs to the order Hymenoptera, family Formicidae. It is a well-known tramp ant species that has achieved a worldwide distribution through human trade, frequently infesting greenhouses, nurseries, and indoor gardens in temperate regions where it survives in artificial climate controlled environments.

Crop impact. The ant primarily affects ornamental plants and greenhouse vegetable crops. While it may occasionally damage roots, the most significant impact is its role as a bodyguard for sap-sucking insects like aphids, mealybugs, and scale insects. By protecting these pests from natural predators, the ants facilitate their massive proliferation on host plants.

Biology and development. Tetramorium simillimum colonies are polygynous, meaning they possess multiple queens, which allows for rapid colony expansion and high survival rates. Workers are small and highly active foragers. They build nests in soil, decaying organic matter, or beneath pots, showing a strong preference for warm and humid habitats found in commercial greenhouses.

Damage characteristics. The presence of this species often leads to severe infestations of secondary pests. Aphids, shielded by the ants, multiply rapidly, leading to plant wilting, stunted growth, and the development of sooty mold, which blocks photosynthesis. Left unmanaged, the ants can compromise the health of entire greenhouse production cycles within a short period.

Control measures. Effective management relies on suppressing both the ant colonies and the pests they protect:

• Targeted baiting using slow-acting stomach poisons to eliminate the queen.
• Rigorous sanitation practices to remove potential nesting sites in pots and soil.
• Regular monitoring and controlling aphid and scale populations to remove the ants' food source.
• Implementing sticky barriers around nursery equipment to prevent foraging movement.