Six subspecies of barn swallow are generally recognised. SLATS received the nickname Tsubame (Japanese for barn swallow) on 14 July 2017. The bird is superficially similar to a large barn swallow or house martin. In flight, it looks paler underneath than barn swallow. "Lasta" is the Serbian word for barn swallow. These are the typical swallows, including the widespread barn swallow. The barn swallow and house martin now rarely use natural sites. The term "Swallow" is used colloquially in Europe as a synonym for the barn swallow. There are six subspecies of barn swallow, which breed across the Northern Hemisphere. The Barn swallow is the national bird of Estonia. Many of these are migratory, including the [[barn swallow]]. The barn swallow is the national bird of Austria and Estonia. The barn swallow, the national bird, is a characteristic guest of Estonian homes. However, in Europe, the barn swallow consumes fewer aphids than the house or sand martins. The barn swallow ("Hirundo rustica") is the most widespread species of swallow in the world.