Leptothorax acervorum is the only species remaining in Leptothorax after the other four British species were moved to Temnothorax (Bolton 2003). L. acervorum are small myrmicine ants with distinct propodeal spines and three-segmented antennal clubs. L. acervorum are larger than the British Temnothorax species and can be distinguished by an 11-segmented antenna in the females (12 in males); the Temnothorax species have one extra funicular segment.
Leptothorax acervorum is widely distributed throughout England, Wales, Scotland and Ireland. It is relatively abundant throughout its range from Cornwall to northern Scotland and can be found quite readily in most areas, apart from extreme urban and intensively agricultural sites. The species is more commonly associated with inland rather than coastal sites. This species occurs from Arctic Scandinavia south to southern Europe, and across Asia to Japan.