Yellow meadow ant (Lasius flavus)

GenusLasius (1)
SizeWorker length: 2 - 3.5 mm (2)

The yellow meadow ant is a common species (3).

This common ant is, as the name suggests, yellowish brown in colour (3). A number of features distinguish it from other similar species of ant, including the fact that the lower sections of the antennae and the tibiae lack hairs (3). The workers are around 2 to 3.5 mm in length (2).

The yellow meadow ant occurs throughout Europe and Britain (4) and found in Japan (2).

The yellow meadow ant is typically found in rough grassland and gardens, providing the grass is not cut too often. This species can live under the ground as long as the grass is open enough to allow sunlight to reach the soil (3).

This species feeds on insects that are found in grass, including fly larvae, wireworms, woodlice and springtails. It also 'farms' aphids on the roots of plants in order to obtain the sweet honeydew that they exude (3).

Like all ants, the yellow meadow ant lives in organised social colonies, consisting of a reproductive female known as the queen, a few males, and a large number of workers, which are non-sexual females (5). During summer, different colonies release winged reproductive males and future queens at the same time. The trigger for their synchronised release is warm, humid air, typically after rain. Mating takes place after 'nuptial flight' takes place, when a male and female form a pair and mate on the wing. After mating the female lands on the ground, sheds her wings and searches for a suitable place to establish a new colony. She will not mate again in her lifetime, but stores enough sperm inside her body to fertilise all of her future eggs (3). This ant lives in colonies underground and, along with the earthworm (Lumbricus terrestris), is very important in bringing matter from a meter or more below ground to the surface of the soil, and maintaining porous soil (3). Colonies occasionally make mound nests in the moist conditions following rainfall or early in the morning when it is still dewy. Their nests are highly intricate, with numerous fine channels made in the soil; the whole structure is reinforced by the roots and shoots of plants, the growth of which is encouraged by the workers, who defecate into crevices in the soil. The mounds usually have one flat face which is oriented towards the south-east, thus maximising the benefits of the early morning sunshine (3). In situations where mound nests would not be ideal (e.g. in sandy soils, which would be eroded quickly), colonies tend to live beneath stones (3).

Like many ants, this species has a special relationship with the larvae of a blue butterfly, in this case, those of the chalk hill blue butterfly. The workers of the yellow meadow ant are attracted by volatile substances that the caterpillar secretes. They may then bury the caterpillar and protect it from predators (3).

There are not currently thought to be any threats to this common and widespread species.

There are not known to be any specific conservation measures known to be in place for this species.

For more information on the yellow meadow ant, visit:

You can see the yellow meadow ant by visiting the Chilterns, Oxfordshire:

This information is awaiting authentication by a species expert, and will be updated as soon as possible. If you are able to help please contact:

  1. National Biodiversity Network Species Dictionary (September 2003):
  2. Japanese Ant Database Group (October 2003):
  3. Brian, M.V. (1977) Ants- the New Naturalist, a survey of British Natural History. William Collins Sons and Co., Glasgow.
  4. Yellow meadow ant (October 2003):
  5. Buczaki, S. (2002) Fauna Britannica. Hamlyn, London.