Lasius flavus, Yellow Meadow Ant

Common Name: Yellow Meadow Ant

Lasius flavus, more commonly known as the Yellow Meadow Ant, is one of the most common ants in the UK. The queen is 7–9 mm long, males 3–4 mm and workers 2–4 mm. Their colour varies from yellow to brown, with queen and males being slightly more darkly colored.

The species lives primarily underground in meadows and very commonly, lawns. The nests are often completely overgrown by grass, however, often their presence is betrayed by small mounds of loose soil material between the grass stalks. They will also nest under large rocks or concrete slabs. Lawn nesting will eventually become obvious as the aphids clear sections of grass or portions of gardens.

The yellow meadow ant feeds on the honeydew from root aphids, which they breed in their nests. During winter, the aphids themselves are sometimes eaten. As a consequence of their feeding habits, the species only occasionally forages outside the nest. Evidence of their underground lives is their lack of pigmentation and the smaller size of their eyes, compared to closely related species like the black garden ant. They are a timid species and will often simply barricade their tunnels to fight off invaders.