The black garden ant (Lasius niger), also known as common black ant, is a formicine ant, the type species of the subgenus Lasius, found all over Europe and in some parts of North America and Asia. The European species was split into two species; L. niger is found in open areas, while L. platythorax is found in forest habitats. It is monogynous, meaning colonies have a single queen. Lasius niger colonies can reach in size up to around 40,000 workers but 4,000–7,000 is around average. A Lasius niger queen can live up to around 15 years and it has been claimed that some have lived for 50 years.