Lasius

Lasius is a genus of ants in the subfamily Formicinae, comprising a large number of species found in temperate regions around the world. Members of the genus are generally small to medium-sized and are often associated with soil or ground surfaces. Common species include Lasius niger, the black garden ant, and Lasius flavus, the yellow meadow ant. Lasius neoniger is another well-known species in North America.

Taxonomy and identification: Like other formicine ants, Lasius species have a single petiole, lack a sting, and possess an acidopore that can spray formic acid for defense. They do not produce a sting as part of their offense.

Distribution and habitat: Lasius ants are widely distributed in temperate habitats and are frequently found in gardens, grasslands, forests, and urban areas. They typically nest in soil, under stones, or in rotting wood, with some species spending much of their life cycle underground.

Biology and life cycle: Colonies may be monogynous (one queen) or polygynous (multiple queens) depending on species. Queens found new colonies by nuptial flights in spring or early summer, after which they often begin life in a claustral manner, relying on their stored reserves. Workers maintain the nest, forage for food, and care for brood.

Diet and foraging: Lasius ants are omnivorous, feeding on nectar, honeydew produced by aphids, seeds, and small arthropods. Foraging often involves pheromone trails that guide workers between nest and food sources.

Ecology and interactions: They play a role in soil turnover and ecosystem dynamics. Some species experience social parasitism, and Lasius nests can be common in human-modified landscapes, sometimes regarded as garden pests.